In the Company of Plants and Rocks

The Many Mysteries of Rock

2012-02-25T17:41:00.000-07:00

A rock climber marvels at the undulating thin cracks on Devils Tower ... how convenient!

Climbers know the rock they climb on intimately. They know the basic types -- sandstone, limestone, granite. They are experts on the nature of the rock surface, whether it is smooth or has features -- tiny crimper edges, big buckets, knobs, pockets, slopers, jugs. They are acutely aware of the angle of the rock face and its height. They know the nature of the fractures -- narrow vs. wide, undulating vs. parallel -- critical for hand and foot holds and gear placement. They worry about the competence of the rock; might those hand holds or even an anchor bolt pull out? Climbers clearly are a ready audience for stories about the geology of their playgrounds.

“Why are there so many offwidths at Vedauwoo?” Jason
Haas wonders, as he makes his way up Main Street (5.10a).

Many climbing guidebooks include something about the geology of the area, but these explanations typically are brief, sometimes just the rock type and its age. Fortunately there is an alternative. Flakes, Jugs, and Splitters: A Rock Climber's Guide to Geology, by geologist/climber Sarah Garlick, covers 50 climbing areas in North America as well as some in Africa, Asia, Australia, Antarctica, South America and Europe. This is an ambitious project! Climbing areas vary widely in rock type and geologic history, and most include at least one geologic mystery. A lengthy paper could be written on each I’m sure.

The book begins with “Geology 101” -- introductory material including geologic time, rock classification and formation (even the tricky classification of granites), plate tectonics, uplift, and weathering/erosion. The main part of the book is organized by climbing area within geographic regions. It would be impossible to provide comprehensive explanations for each, and so Garlick focuses instead on specific geologic features, for example the steepness of New River Gorge in West Virginia, the high elevations of the Rockies in Colorado, the parallel-sided splitter cracks of Indian Creek in Utah, and the cavernous hollowed-out huecos of Hueco Tanks in Texas. Each section starts with a question: “Why are there big walls in Zion?”, “What are all those chicken heads at Cochise Stronghold?”, “Why isn’t there rock climbing in Florida?”

How old are the Grand Tetons? ... depends on what you mean. They are composed of some of the oldest rock in North America (the granite is 2.5 billion years old, the gneiss 2.7!) but are among the youngest mountains, uplifted less than 2 million years ago.

Though organized by area and focused on specific features, the book includes more than just local geology. Garlick does a good job of describing the bigger picture. For me, the explanations of plate movements, collisions, rifts, jostling and passive margins and how they relate to climbing areas are the most interesting parts of the book. For example, we can’t explain the Gunks in New York without invoking 1) mountain-building 450 million years ago when a chain of islands collided with the eastern margin of North America, resulting in erosion and deposition of sediments that would become the hard conglomerate we climb on; and 2) tectonic compression 300 to 250 million years ago during the formation of Pangaea that tilted the strata and produced those bomber holds, making some of the big Gunks roofs surprisingly easy to climb. Thank you plate tectonics.

Bigggg roof but only 5.8. Photo by Mike Freeman, from Dick DuMais'
Shawangunk Rock Climbing, 1985. Posted at SuperTopo.

A well-illustrated brief overview of the history of the Appalachian Mountains is presented in a three-page “sidebar”, providing the context for many of the climbing areas in the eastern US. A similar approach is used for the Rockies (“A Short History of Colorado”). Other shorter sidebars explain diverse topics such as the multitude of granite plutons in California, the Ancestral Rockies and the mysterious Gunks quartz. There are ample illustrations of geologic phenomena and processes throughout: plate tectonics, uplifts and basins, stratigraphic columns, salt anticlines, metamorphic core complexes, ancient landscapes and many more. And of course there are spectacular photographs of crags and climbers. This is a book worth perusing from cover to cover, in addition to studying one’s favorite crags -- perhaps a good diversion for rainy days.

Excerpt from "A Short History of Colorado"; click to view.

Given the number and diversity of rock climbing areas, this kind of book can provide only a quick look at a selection of crags. For example, discussion of Devils Tower includes just one of the theories behind this puzzling rock, but that’s understandable -- it has proven to have a history mysterious enough to support multiple possible explanations. Less than a page is devoted to Yosemite Valley, in spite of its important place in the history of climbing (but see also the granite of the Sierra Nevada). The Adirondacks are omitted entirely. Even so, I think Garlick has made good choices about what to include; the result is a collection of interesting wide-ranging stories about the diverse materials and histories of the mountains and rocks we climb.

If you are a geologically-challenged climber, this book will make a bit of a geologist out of you and I bet you will enjoy it, even though sections may prove to be somewhat technical (a glossary would have helped). If you are a geologist that climbs, the book provides introductory material as well as references for further research. I am an amateur geologist and casual climber -- for me, it was a great read and will be a good reference in the future.

Flakes, Jugs, and Splitters: A Rock Climber's Guide to Geology by Sarah Garlick. 2009. FalconGuides. Paperback, 224 pages, ISBN 0762748370. $13.59 from Amazon

F, J, & S won Best Book in the Mountain Exposition category at the 2009 Banff Mountain Film Festival.

Other reviews can be found at:

About.com on climbing

The climber website summitpost.org

Rock and Ice magazine

Devils Tower -- what’s on top?

2012-02-23T17:53:00.000-07:00

Devils Tower, in the Black Hills in northeast Wyoming, USA.
Photo by John C. H. Grabill, ca. 1888.

Devils Tower National Monument is a small park containing a huge rock -- a giant truncated fluted monolith that rises 800 feet above the pine ridges and prairies of the northwest Black Hills. The park is only about a square mile in area, with a significant chunk of that taken up by igneous intrusive rock (phonolite porphyry), but it includes a good representation of the area’s vegetation: ponderosa pine forest; woody draws with bur oak, green ash, hawthorne, chokecherry and wild plum; mixed grass prairie; and riparian woodland along the Belle Fourche River. But what’s on top?

Devils Tower from the air, middle left; Belle Fourche River on right has exposed
Permo-Triassic redbeds of the Spearfish Formation. Courtesy ArcGIS Online.

The broad rolling summit of Devils Tower is covered in rocks, grass, cactus, wildflowers, and surprisingly, sagebrush -- specifically Wyoming big sagebrush, Artemisia tridentata ssp. wyomingensis. Why is this a surprise? because big sagebrush is uncommon in the Black Hills, restricted to the margins of the uplift. It is characteristic of drier habitats in the basins to the west. The Black Hills, even at lower elevations, are more mesic (moist), with forests, woodlands and relatively-lush mixed-grass prairies, like those of the Great Plains to the east.

Photo on left courtesy USGS Photographic Library.

Climber on summit sits next to Wyoming big sagebrush; turkey vulture in distance.

It’s wonderful when nature surprises us like this -- it gives us a chance to think and speculate, to come up with an explanation. Although the top of the Tower receives the same amount of precipitation as the surrounding area, I suspect is it effectively drier due to the rocky substrate with limited soil development. Sagebrush is better suited for this site.

Collecting vegetation data on the summit of the Tower ... someone has to do it.
Little Missouri Buttes in background are igneous intrusions similar to Devils Tower.

At least 28 vascular plant species grow on the summit of Devils Tower, including several others characteristic of the sagebrush grasslands of the basins to the west, such as prickly pear cactus and bluebunch wheatgrass.

What's on top:

western yarrow (Achillea millefolium)

wild onion (Allium textile)

fringed sagebrush (Artemisia frigida)

Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis)

rockcress (Arabis holboellii)

blue grama (Bouteloua gracilis)

cheatgrass (Bromus tectorum)

sego lily (Calochortus nuttallii)

harebell (Campanula rotundifolia)

field sedge (Carex praegracilis)

one-spike oatgrass (Danthonia unispicata)

western tansymustard (Descurainia pinnata)

small draba (Draba nemorosa)

Junegrass (Koeleria macrantha)

stickseed (Lappula redowskii)

plains muhly grass (Muhlenbergia cuspidata)

prickly pear cactus (Opuntia polyacantha)

broomrape (parasitic on sagebrush) (Orobanche fasciculata)

Sandberg bluegrass (Poa secunda)

cinquefoil (Potentilla pensylvanica)

bluebunch wheatgrass (Pseudoroegneria spicata)

skunkbush (Rhus trilobata)

gooseberry (Ribes setosum)

spike moss (Selaginella densa)

needle-and-thread (Stipa comata)

meadow salsify (Tragopogon dubius)

sixweeks fescue (Vulpia octoflora)

woodsia fern (Woodsia sp.)

Summit ca 1970. Sign reads NO CLIMBING ABOVE THIS POINT.

Devils Tower National Monument is located near Hulett, Wyoming, in the
northwest part of the Black Hills. Courtesy Google Maps.

Accretionary Wedge #43 -- deadline approaching

2012-02-22T17:19:00.001-07:00

REMINDER The deadline for AW#43 is February 29, only a week away. Get your entries in, otherwise you will be seeing more of my favorites, maybe even plants!! :)

Contributions accepted here:

Call for Posts: Accretionary Wedge #43, “my favorite geological illustration”

Pinus sp. Rubber stamp art by Jan Conn.

Leaving Home

2012-02-19T19:01:00.000-07:00

Your children are not your children.

They are the sons and daughters of Life's longing for itself ...

You are the bows from which your children as living arrows are sent forth.

Kahlil Gibran, The Prophet

Do you remember leaving home? I do -- like many teenagers, I could hardly wait and I seized upon Gibran’s words when I read them. Now years later they still make sense to me, though they seem a bit maudlin. But the feelings of a parent (which I am not) are very different ... a human parent, that is. Isn't it interesting that many humans have a hard time letting their children go, while most animals and plants take the opposite approach -- rebuffing, excluding and even hurling their progeny into the unknown.

Plants will go to great lengths to send their propagules packing. Some seeds simply fall to the ground and never go much further, but many are dispersed far and wide. Most end up in inhospitable places with their mission unfulfilled, but some will colonize new sites and even expand the range of the species.

Wind and water are common means of scattering seeds, and plants have many adaptations for these vectors. Among the more familiar are the plumose seed tails of dandelions (above, courtesy The Guardian) and the buoyant outer coat of the coconut (below).

Some plants enlist animals, a strategy called zoochory. Seed transport internally is called endozoochory; epizoochory refers to transport on the exterior of an animal. Epizoochory is a relatively rare means of seed dispersal, used by less than 5-10% of all plant species, but it can be quite effective, especially if the animal is wide ranging (Sorenson 1986).

To right, Sparky participates in epizoochory (click to view).

Adhesion mechanisms for epizoochory include sticky mucus and, more commonly, structures such as barbs and hooks. The hooks on the burrs of burdock (Arctium spp., photo to left) were the inspiration for Velcro. In 1948, Georges de Mestral, a Swiss electrical engineer, was pulling burrs from his dog’s fur after a day of hunting, and became curious as to what gave them their adhesive power. A look under the microscope revealed a fearsome array of hooks, prompting de Mestral to wonder if something similar could be constructed for use as a reversible fastener. By 1951 he had a working product, the first patent was granted in 1955, and after additional refinement, Velcro was introduced commercially in the late 1950s. Though slow to be accepted initially, it eventually became so popular that the registered trademark “Velcro” is now a generic term for hook-and-loop fasteners around the world. The interesting story of the “zipperless zipper” can be found here.

Velcro up close -- hooks on left, loops on right.

The burrs that Sparky brought home are from our wild licorice, Glycyrrhiza lepidota. The name of the genus comes from the Greek glykys -- sweet -- and rhiza -- root. Roots of most species of Glycyrrhiza contain glycyrrhizic acid, the active ingredient of the sweet distinctively-flavored extract used in tobacco products, pharmaceuticals (to mask bitterness), beverages (foaming agent) and of course candy, although many “licorice” candies now contain anise instead.

Commercial licorice products come from the cultivated licorice, Glycyrrhiza glabra, but the root of our wild licorice was once a source of sweetener as well, for Native Americans and early settlers in the western United States. Today, wild licorice root is used in herbal and homeopathic remedies (here for example). Glycyrrhizic acid is known to have beneficial medicinal effects, mainly in diseases related to cortisol regulation, and the biochemical pathways and physiological mechanisms have been elucidated. However it is dangerous in large dosages, causing hypertension and even death. Dalton (2002) provides a succinct overview of the benefits and dangers of glycyrrhizic acid.

Glycyrrhiza lepidota, wild licorice (click to view).

Wild licorice (also called American licorice) is native to and widespread in North America, growing in many different habitats. It is a robust perennial herb that can reach four feet in height. The underground part of the plant is robust as well, consisting of an extensive network of rhizomes and fleshy roots that produce adventitious shoots; thus wild licorice is rarely found as a single above-ground plant, but rather as large colonies. It is excellent browse for both wildlife and cattle (USDA NRCS), and yet is classified as a weed in many US states, for example Wyoming, North Dakota, Missouri and Nevada, probably due to its ability to persist and expand with disturbance. The burrs are more clearly a hazard for sheep ranchers, causing dockage if present in wool.

Single wild licorice leaf with
leaflets pinnately arranged.

Wild licorice is a member of the pea family (Fabaceae), and like many peas, its leaves are pinnately compound, i.e. subdivided into leaflets arranged along the axis of the leaf. Look closely at the photo below and you can see that the leaves are glandular punctate, with tiny round resinous glands.

Close-up of wild licorice leaf; from Matt Lavin’s Flickr site devoted
to the plant diversity of sagebrush steppes. Click to view glands.

The flowers of the wild licorice are like most pea flowers, with characteristic petals -- a banner, two wings and a keel (photo above from CalPhotos; illustration to right from Montana Plant Life). And like all members of the pea family, its fruit is a legume. But what legumes! ... not exactly something you would put in the soup pot.

Legumes (fruit) of wild licorice -- also known as burrs.

By fall, the pretty flowers of the wild licorice are gone and the leaves have withered and died, leaving only standing dead stalks topped with menacing legumes. The wise walker with a dog avoids wild licorice patches this time of year. The tiny hooks are very tough, and sometimes burrs can be removed only with scissors.

With time the tissues soften, and by late winter it’s fairly easy to pull licorice burrs from dog fur. By late spring, when the first new green growth is appearing, the previous year’s fruit are gone -- dispersed to parts unknown, and it is again safe to walk the river trails.

Sources (in addition to links in text above)

Dalton, L. 2002. What’s that stuff? Licorice. Chemical & Engineering News 80: 37.

http://pubs.acs.org/cen/whatstuff/stuff/8032licorice.html

Sorenson, A.E. (1986) Seed dispersal by adhesion. Annual Review of Ecology and Systematics. 17: 443-463.

USDA Forest Service Fire Effects Information System -- Glycyrrhiza lepidota. Accessed February 2012.

http://www.fs.fed.us/database/feis/plants/forb/glylep/all.html

USDA PLANTS Database -- Glycyrrhiza lepidota. Accessed February 2012.

http://plants.usda.gov/java/nameSearch?keywordquery=glycyrrhiza+lepidota&mode=sciname&submit.x=0&submit.y=0

USDA National Resources Conservation Service. Plant Fact Sheet for Glycyrrhiza lepidota. Accessed February 2012. http://plants.usda.gov/factsheet/pdf/fs_glle3.pdf

The Spiritual Side of Mud

2012-02-16T07:30:00.001-07:00

Some folks say a man is made out of mud.¹ Some would disagree. But no one who lives in this part of North America would deny that sometimes a man is covered in mud. Dog feet are sometimes covered in mud too, leaving prints all over the kitchen floor on otherwise-wonderful days when the sun is out, temperatures rise well above freezing and the snow melts in the yard. Mud sometimes covers shoes and then turns hard as rock, relegating them to the pile of old-shoes-for-bad-weather-days. Mud makes field work no fun what-so-ever.

To left, Clay covered in mud after a mountain bike race in southeast Wyoming, USA.

Where I live, people both despise mud and fear it. The mud that develops on Cretaceous shales in the plains, basins and foothills is annoying at minimum and terrifying at its worst. It is sticky and slippery at the same time, and dirt roads through badlands and breaks can send vehicles sliding down slopes on a rainy day. If you’re lucky, you only get stuck.

Cretaceous mud in South Dakota.

“The thing about gumbo is that you really can't describe to people what it's like, unless they've been stuck in it. You tell them it gets muddy, and they say they've seen mud. When you tell them they haven't seen mud like this, they just don't believe you” (Jack Horner, paleontologist, eastern Montana).

Stuck ... ca 1940; no source given.

What gives mud its evil powers? That would be clay, the smallest of the soil separates (particles). Soil with large amounts of clay absorbs water easily, and is sticky and slippery when wet. Most soils turn into mud when water is added, but clay-rich soils produce the most memorable mud. Table courtesy US Department of Agriculture.

Being so small, a clay particle has a large surface area compared with its volume. Most clays are flattened or flaky, making surface tension attraction especially strong. And yet clay particles also slide past each other easily with the right amount of moisture, giving clay its characteristic plasticity and slipperiness. Scanning electron micrograph of clay on left.

Clay-rich soils are not all bad. Clay holds nutrients as well as water, and shallow-rooted plants, especially grasses, thrive on these soils. But when the vegetation is removed, the evil mud appears.

Montgomery Potrero -- grasslands on shale on the crest of the Sierra Madre, California.

And yet mud in the proper context can be beautiful, awe-inspiring, spiritual. Consider adobe. Even the name is appealing. “Mud” is a single blunt syllable but “adobe” flows from one soft sound to the next. Made of simple sounds, the word is lovely in a straightforward way, like a mission church made of simple adobe walls.

Misión La Purísima Concepción de María Santísima, near Lompoc, California.

San Francisco de Asis church in Rancho de Taos, New Mexico.

I am always moved by the impressive silence inside thick adobe walls. On one occasion I was the only visitor in the San Francisco de Asis mission church. As I sat amidst the colorful and mystical decor -- the Virgin, her Child, and a mulititude saints -- there were absolutely no sounds other than my breath. In such stillness it might indeed be possible to escape the world outside, to contemplate other realities.

Adobe has long been used for construction. Being mud, it becomes rock-hard when it dries, the clay particles adhering tightly to each other. The correct mix of particle sizes is critical. Too much clay and the adobe will shrink and crack with drying; clay must be less than 30% of the mix. Traditionally, organic matter such as straw or manure has been added. Some consider it critical and analogous to rebar, but it is not structurally necessary and can lead to insect damage or rot, weakening the adobe. Sand is preferred.

Even the best adobe will succumb to moisture, eventually disappearing altogether in the absence of protection. An impervious roof is required.

Tejas at Misión La Purísima.

The undulating earthy-red mission roofs that shed rain so effectively were mud-based as well. Tejas (roof tiles) were shaped by molding clay over logs, and then were baked. Often there was no good source of clay nearby, and instead it had to be extracted from mud in settling ponds.

Mud can be used to coat the exterior of straw bale buildings. If it contains the right amount of clay, it can be pressed and smeared to make a smooth or textured surface that hardens without cracking. A finish, such as stucco or whitewash, protects against moisture. To left, Danny has good mud on his property, with the right amount of clay

Below, the “church” under construction -- a straw bale observatory where seekers, with the aid of telescopes, will look beyond this world to the heavens.

Mud on straw -- what could be more organic? even feels a bit spiritual!

Danny is seized by the Power of Mud.
Western Sky Planetarium, serving western Colorado and southern Utah.

Sources

¹Sixteen Tons, written and first recorded by Merle Travis, 1947 (Folk Songs of the Hills):

Now some people say a man’s made out of mud

But a poor man’s made out of muscle and blood

Muscle and blood, skin and bone

A mind that’s weak and a back that’s strong ...

The Cooperative Soil Survey (Missouri)

http://soils.missouri.edu/tutorial/page8.asp

Soil texture; from Wikipedia, the free encyclopedia

http://en.wikipedia.org/wiki/Soil_texture

A Virtual Tour of the California Missions: Mission Materials

http://missiontour.org/related/adobe.htm

from New Mexico State University: ABCs of Making Adobe Bricks

http://aces.nmsu.edu/pubs/_g/G-521.pdf

Yuccas of the Far North

2012-02-12T10:27:00.001-07:00

What are these plants doing, besides advertising for Walmart?

They are photosynthesizing. While other grassland plants have shut down for the winter, Yucca glauca continues to crank out sugars when the sun is shining and temperatures are not too low. The tough fibrous leaves are resistant to freezing and desiccation, and their steep angles are conducive to catching rays when the sun is low in the sky.

The Great Plains yucca, aka soapweed or soapweed yucca, is adapted to a broad range of climatic conditions, reflected in its distribution. It the most widespread of North American yuccas, growing in grasslands of the Great Plains from north Texas to the southeastern tip of Alberta. Map courtesy Flora of North America.

Yucca glauca does especially well in sandy soils, probably due to less competition from other plants. It is scarce to absent in areas covered in grass. The plants are deep-rooted and rhizomatous, often forming colonies of rosettes that are connected underground.

Yucca colony on sandy soil on slope of small ridge in grassland;

southeast Wyoming, USA.

In Wyoming, yuccas bloom in June and July, producing large cream-to-greenish flowers that are tasty to people as well as to deer and other wildlife. But on this winter day, yucca flowers are only a dream.

Photo by Lillian G. Flaigg; Lady Bird Johnson Wildflower Center.

Great Plains yucca provides a bit of greenery in an otherwise-drab midwinter grassland.

Blog Crawl Gems

2012-02-10T11:29:00.002-07:00

Recent Treasures: academic publishing and power to the people; personal privacy -- do we really want it?; chloroplast slurpies; the Great Unconformity; beyond plate tectonics.

The Economist took a look at the financial success of the academic publishing industry, where authors pay large sums to publish, and readers do the same to read. Some publishers employ rather devious strategies, for example requiring libraries to subscribe to bundles of journals not just the ones they want. No wonder a boycott of Elsevier has taken off. Are the giants about to lose their grip, especially now that the internet makes communication so much easier and cheaper? For additional discussion and links, see this recent post at Nature/news.

Google’s new privacy policy is looming on the horizon, to go into effect March 1, and CHIMERAS provides an interesting discussion on the topic. So the struggle continues -- between our fear of someone knowing too much about us, and our irrepressible social nature.

The January plant blog-carnival, Berry Go Round #48, links to many great posts, including one on sea slugs that suck chloroplasts out of algae and then use them for ... photosynthesis! Yes, solar-powered sea slugs.

Elysia chlorotica, a
"lurid green sea slug"
according to New Scientist.

There is an entire site devoted to these guys; here you can see for yourself sea slugs slurping chloroplasts. In an earlier BCG, I mentioned that microbes are known to steal chloroplasts, but a slug? wow. There now is a name for these stolen plastids -- kleptoplasts :) An important question is how the plastids are stabilized in the slug. In their normal environment, plastids are maintained in part by nuclear genes, but surely these are left behind when the chloroplasts are stolen ... or not? There is a bit of evidence that the new host, the sea slug, may have the necessary nuclear genes ... maybe stolen from the alga ... maybe.

Next is a slightly older post, perhaps you’ve read it already. If not, I highly recommend The Great Unconformity of the Grand Canyon by Written in Stone. This is a lengthy post with lots of photos, about the fascinating Great Unconformity between the lower Cambrian, ca 500 million years bp, and the Paleoproterozoic, ca 1700 million years bp -- a gap of more than a billion years. In the Grand Canyon, the gap is represented by early Cambrian Tapeats sandstone resting on early Proterozoic Vishnu schist (photo below). This is only part I, “Defining It”. I look forward to the next installments.

Vishnu contemplates the Great Unconformity in the Grand Canyon.

Finally, Metageologist posted an introduction to continental tectonics and why plate tectonics is not enough. The assumption that continental plates are coherent rigid structures does not work in explaining the very broad zones of deformation seen. I should know ... the current Wyoming landscape was shaped mainly by the Laramide Orogeny, when plate collision and other plate motion along the west coast of North America resulted in as much as 40,000 feet of structural relief here a thousand miles to the east.

Why the Himalayas are not important -- they are only the front edge of the
Tibetan Plateau (see Metageologist's post for further explanation).

Metageologist includes a link to Peter Molnar’s 1988 Nature paper, Continental tectonics in the aftermath of plate tectonics, not freely available of course. You can access From Plate Tectonics to Continental Tectonics -- part review, part memoir -- via Molnar’s website.

Plants & Rocks: ferns and granite ... and climbers

2012-02-06T20:03:00.000-07:00

This post is a tribute to pioneer rock climber Herb Conn, who passed away last week at age 91. Actually, it is a tribute to both Herb and his wife, for I never thought of Herb without also thinking of Jan; it was always “Herb and Jan” or “the Conns”.

Herb and Jan were in their 20s when they gave up their home and work in Washington DC for freedom and the open road. They outfitted their vehicle for camping, left the Establishment behind and went climbing. This is a common lifestyle among my friends, and wouldn't seem so unusual except that it was shortly after World War II when the Conns dropped out. They were pioneer climbing bums -- wandering from crag to crag in their 19-thirty-something panel truck, living simply and cheaply, picking up a little work here and there, and climbing rocks. They never gave up that lifestyle, even after they "settled down" in western South Dakota.

The Cathedral Spires in the Black Hills Needles, South Dakota, USA.

Herb's guidebook to the Needles;
self-published, ca 1957.

The nomadic life ended when the Conns arrived in the Black Hills and saw the seemingly-endless granite spires, fins, towers, domes and other fantastical shapes. “We knew we had found the place we wanted to live” said Jan; they were “two cats in an untended fish market” according to Herb. The Conns went on to make nearly 220 first ascents in the Black Hills Needles.

from forums.caves.org

In 1959 Herb and Jan were converted to caving, and ended up exploring 60+ miles of passages in what had been considered just a minor cave. The "Jewel Cave Adventure" is quite a story, but we'll save it for the future.

By the time I got to know the Conns in the mid 1990s, they had given up caving and were back into rock climbing (Herb was 76, Jan a few years younger). They told me about an interesting fern they sometimes saw in cracks in the granite; they hoped I could tell them what it was. We headed out for a look and found the maidenhair spleenwort, a very pretty fern indeed! I pointed out the grassy-looking forked spleenwort growing nearby, which Jan called “second-rate” with its scraggly demeanor.

To right, maidenhair spleenwort growing in crevice in 1.7-billion-year-old Harney Peak granite. Photo by Larry Ebbert.

Then the plot thickened. We found a Mystery Fern which I could not identify, even back in the herbarium. I sent a specimen to Robbin Moran of the New York Botanical Garden, who identified it as the alternate-leaved spleenwort, at that time known from only three locations in the US, all on the East Coast.

To left, the alternate-leaved spleenwort (the Mystery Fern) growing above the forked spleenwort. Photo by Larry Ebbert.

The Conns and I published our findings in the American Fern Journal, but the story is best told in Jan’s illustrated account below, click to read.

The alternate-leaved spleenwort grows in
well-shaded habitat; rock climber for scale.

One of Jan’s many talents is rubber stamp art. Here is a story about the Conns' fern adventures. Stamps by Jan, script by Hollis (click to read).

Jan writing about ferns; Herb eyeing a new climbing route?

Herb belaying Jan on 3BT (3 Billion Tons, a really big rock).

Heading home after another day on the rocks.

For more Conn lore:

The Conns and ferns:

Marriott, H.J., Jan and Herb Conn. (2000). "Asplenium X alternifolium in the Black Hills of South Dakota". American Fern Journal 90: 109.

The Conns and caving:

Conn, Herb and Jan. 2000. The Jewel Cave Adventure: Fifty Miles of Discovery under South Dakota. Cave Books.

The Conns and climbing:

Stephens, Lindsay. 2008. South Dakota Needles: Adventure Climbs of Herb and Jan Conn. Boulder, CO: Sharp End Publishing.
Among the highlights of this book are entertaining excerpts from the Conns' journals. Infinitely-many thanks to Lindsay for collecting and sharing the wonderful Conn stories, as well as documenting the Conn routes in the Needles. If these routes seem terrifying now, imagine climbing them in smooth-soled sneakers with only pitons for pro!

Fresh out of the Wormhole on Spire Four, my favorite Needles route.
First ascent: Herb and Jan Conn, June 30, 1948.

UPDATE: Daryl S. of Sylvan Rocks Climbing School and Guide Service has put up a nice post about his friends the Conns.

Call for Posts: Accretionary Wedge #43, “my favorite geological illustration”

2012-02-05T20:52:00.000-07:00

Last November I wrote about my favorite geological illustration, a striking aerial view of the Black Hills from the report of the 1875 Newton Jenny Expedition. Ron Schott of the Geology Home Companion Blog asked if I would host an Accretionary Wedge on the topic. "Of course!" I replied. (I hope there are no other plans for AW#43 out there ... if so, please let me know).

All types of geological illustrations qualify -- drawings, paintings, maps, charts, graphs, cross-sections, diagrams, etc., but not photographs. You might choose something because of its impact, its beauty, its humor, its clear message or perhaps because of a special role it played in your life. Let us know the reasons for your choice!

You can leave a link to your post as a Comment below, or if you don’t have a blog, a link to the illustration with an explanation. I’ll include everything in a roundup at the end of the month (deadline is February 29).

Geological illustrations currently on display at the

University of Wyoming Geology Museum.

The top 10 reasons I love Wyoming geology

2012-02-04T21:05:00.000-07:00

University of Wyoming spring field trip, 1925. Photo by S. H. Knight, Professor of Geology.

Courtesy American Heritage Center, used with permission.

A spontaneous meme is spreading through the geoblogosphere. The theme is: why we love our particular specialty in geo-science. Erik Klemetti posted about volcanoes, Siim Sepp about sand, Callan Bentley about structural geology, and Silver Fox about detachment faults and core complexes. I’m an amateur geologist without a specialty, so instead I will explain why I love the geology of my home state, Wyoming.

1. It’s fun to be in the field in Wyoming -- lots of public land, not many people, the folks I do meet are friendly and even thrilled to find someone to chat with for awhile.

Photo by Duckboy. Duckboy postcards are fantastic! I highly recommend this collection, an astute sociological study of our state: The Duckboy Way or Quack in the Saddle Again

2. When I can’t be in the field, I can enjoy aerial photos and geologic maps -- beautiful in their own right.

Bighorn Basin in northwest Wyoming, a classic Laramide syncline (click to view).

3. Wyoming’s Laramide uplifts, superpositioned drainages and relic periglacial features bring back many fond memories of geotripping when I was a grad student ... in botany :) The extra time it took to finish my degree was a good investment. Geology is fun!

4. All of my dogs have loved Wyoming geology, especially the field trip part. To right, Ellie studying phonolite porphyry at Devils Tower.

5. We get to go camping!!

6. Wyoming has 1.7-billion-year-old fossil stromatolites in a gorgeous subalpine setting.

7. Just 12,000 years ago, conditions in many of Wyoming’s basins were periglacial, and it’s easy to find fossil frost wedges in road cuts and dumps around the state.

8. Wyoming geology is quite old as well. We have lots of Archean cratonic rocks and there is a Precambrian suture just north of where I live.

Modified after Frost et al. 2006. Archean crustal growth ... in the south-central Wyoming Province.

Can. J. Earth Sci. 10: 1533-1555.

9. Much of Wyoming geology is comprehensible to a lay person. Laramide uplifts are especially easy to see and understand, a wonderful way to peer into the the past.

Sheep Mountain anticline; note superpositioned drainage (Big Horn River).
Courtesy ArcGIS online.

10. Wyoming geology is visible. In our high dry climate vegetation is relatively sparse -- a good thing because as I learned in my geomorphology class, plants obscure the landscape!

Sheep Mountain, looking north along crest of anticline. Photo by musicman82.

The photo not taken

2012-02-04T10:37:00.001-07:00

Another magical winter morning -- cold and still, fresh snow, frosted trees, ice decorations along the river -- all in soft gray fog and very fine snow. I wish I could share what I saw on my walk this morning, but it was impossible to photograph; I didn’t even try.

Fortunately, in my mind I can still picture the intriguing dances of light that sprang up when the sun began to shine through the mist. I was looking east across the river when the fine snow condensing out of the fog started to sparkle with bursts of golden light. Each flake flashed for an instant when at just the right angle ... soon there were hundreds of sparkling dancing tiny snowflakes!

It looked as though someone were pouring very fine gold into the river. All I could do was stay and enjoy the moment. Such dynamic and ephemeral beauty is for the eye and the mind, but not for the camera.

Now back at home the sun is shining through the frost on the window ...

... and everyone is happy!

Creatures of Stone III -- the rest of the story?

2012-02-01T21:26:00.000-07:00

Tors at Vedauwoo, southeast Wyoming, USA.

Several months ago, I thought I would write about tors -- those puzzling isolated outcrops of rock, often granite, that look like bizarre beings or the remains of castles or even stacked sacks of wool. There are some rather spectacular tors nearby on the crest of the Laramie Range, and given that they are just 15 miles east of a university where the Dept. of Geology and Geophysics “because of its location ... is ideally suited to provide its students with unparalleled opportunities for field study”, I figured there would be multiple theses, dissertations and papers available.

The first geologist to characterize our tors probably was Ferdinand V. Hayden of the US Geological and Geographical Survey of the Territories. In 1870, he led an expedition through Wyoming Territory, first heading north from Denver along the east flank of the Laramie Range, then called the Black Hills. He was especially impressed with the “picturesque” massive feldspathic granites of the high country.

Granite of the Laramie Range ("Black Hills"), 1870. WH Jackson photo.

“The granites afford most excellent rock studies of their kinds [emphasis added]. The tendency to weather into rounded forms by exfoliation and the jointing are finely shown. The principal lines of fracture are mostly continuous, and have a strike east and west, while the other set trend nearly north and south. The tendency to exfoliate by the stripping off of their concentric layers has enlarged the openings, sometimes several feet. The granites are thus divided irregular rhomboidal masses, many of which have fallen down at the foot of the ridges, and by exfoliation have become so rounded that they appear like immense transported boulders.”

But Hayden’s opinion and my intuition turned out to be wrong. It is hard to find information about tor geology, especially for the Laramie Range tors. The Wyoming State Geological Survey offers nothing, nor does the Forest Service, which manages much of the area. An extensive literature search produced two papers on our local tors, both from 1969. Finally, the University library’s copy of Landforms and geology of granite terrain (Twidale and Vidal Romaní 2005) was checked out to faculty until the semester ended (gripe). Instead of a post about the geology of tors, I put together a photo essay with selected tors from around the world, including pink elephants, barns, a favorite wife, several with mystical powers, and some of our locals.

Pink elephants at Elephant Rocks State Park, Missouri.

A month ago, I finally had enough material to write about tor formation. The generally accepted theory involves a two-stage process. First, fractured granite is weathered underground to create the sculpted forms -- boulders, stacked rocks, domes. A cover of weathered granite (regolith) builds up over the solid rock, and fills the fractures (grus). Then when conditions are right, for example when the area is uplifted and eroded, the weathered material is quickly removed (geologically-speaking), leaving sculpted rock forms standing above the surface. For a detailed explanation please see the previous post.

Two-stage process of tor formation; click to view.

This final post was to be about the tors of the Laramie Range, also known as the Crow tors, and would explain one last piece of the story. Why are there are only isolated clusters of tors? Why is everything else eroded away?

Near Crow Creek, Laramie Range (Laramie Council of Industry 1924).

Alas, there appears to be no clear explanation. Here I summarize what I found, with a promise of pretty pictures afterwards. But first, briefly, the setting.

The Laramie Range is typical of uplifts of the Laramide Orogeny, the mountain-building event responsible for the Rocky Mountains. It is a broad-backed anticline with Precambrian igneous and metamorphic rocks exposed at the crest, and younger sedimentary rocks on the flanks. In the southern part of the range, the broad crest is especially prominent. It is underlain by the 1.4-billion-year old Sherman granite, and is called (predictably) the Sherman surface.

Interstate 80 traverses the Sherman surface on the crest of the Laramie Range, and
will descend gradually to Cheyenne on relic Miocene topography -- the Gangplank.
Vedauwoo tors visible in distance. Courtesy Wyoming DOT.

Uplift of the Laramie Range began in the late Cretaceous, ca 80 million years ago, accompanied by downwarping of the adjacent basins. There were several cycles of uplift and erosion, with the latest uplift in the late Eocene. Subsequently, during Oligocene and Miocene times, sediments eroded off the highlands filled the adjacent basins, eventually lapping high onto the uplift.

Late Cretaceous - Cenozoic history of a typical Laramide uplift (condensed version).
Click to view. After S.H. Knight by way of B. Mears, Jr. (1984).

Beginning in the late Pliocene, stream rejuvenation, possibly due to epeirogenic uplift, resulted in renewed erosion and exhumation of the old landscape. Virtually all Tertiary sediments have been removed except for a relic patch on the east side of the range near Cheyenne. This is the Gangplank, a remnant of Miocene topography that still laps evenly onto the Sherman surface.

Cross-section through southern Laramie Range; on southeast flank, relic Tertiary
strata lap onto Sherman surface (after Mears 1984). Click to view.

Thus we have the necessary players in tor creation -- fracturing of the Sherman granite with uplift, sufficient time for weathering of the fractured granite underground, and erosion for removing regolith to reveal the sculpted granite, with grus cleaned out of the fractures. But why are tors where they are? Is there something about the Sherman granite that might explain the differential weathering and/or erosion, resulting in isolated tors?

Cunningham (1969) suggested variable fracturing of the granite. Areas of close fracturing would weather more rapidly, with the rock completely reduced to regolith with enough time. The erosion that followed would leave a fairly flat, rolling surface -- the Sherman surface. The flatness of this surface may have been controlled by relic geomorphology -- perhaps a Precambrian peneplane. Smaller tors and boulders represent areas of medium fracturing. Massive domes and walls developed from widely-jointed rock.

Wall-like tor at Vedauwoo.

Cunningham provided no evidence for differential fracturing aside from the end results themselves, and made clear that this was a possible explanation only. He described the limited below-ground data available for the Sherman granite. Irregular occurrences of rotted granite to 50 feet thick were observed in a gravel quarry. Alternating layers of rotted and solid rock had been found in a well bore as well.

Eggler et al. (1969) recognized two facies within the Sherman granite in the southern Laramie Range. The Trail Creek granite was associated with much of the rolling Sherman surface: “So reliable is this relationship that where Trail Creek granite stops, the Sherman surface stops and is replaced by a more rugged, outcrop-dominated topography.” Several other surfaces developed on this Trail Creek facies were found a short distance south in Colorado. The clusters of tors were associated with what Eggler called the Cap Rock quartz monzonite, as well as other crystalline rock types.

Tor complex rises above rolling topography of Sherman surface.

Eggler et al. attributed differential weathering to “extensive high-temperature oxidation of Precambrian age” affecting principally the opaques and biotite of the Trail Creek granite. “Formation of hematite along biotite cleavages expanded the mineral” allowing later weathering to proceed rapidly in comparison with non-altered rock. Alteration in Cap Rock quartz monzonite was “minimal” making it more resistant to weathering.

Igneous petrology is something I know almost nothing about, but that doesn’t keep me from wondering about Eggler et al.’s conclusions. In their analyses they looked only at grus -- so how they can conclude that alteration occurred during the Precambrian, rather than later during long periods of burial with extensive regolith development? Also, if there indeed is significant variation in the Sherman granite with regards to weatherability, how does it compare with the differential weathering of granite above and below ground? Underground weathering can proceed rapidly, and may accelerate as regolith develops (Twidale and Vidal Romaní 2005). If Tertiary fill did indeed lap high onto the granite core of the uplift for prolonged periods of time, perhaps accelerated weathering due to burial was the greater factor in reduction of granite to grus. At highest elevations, some outcrops would have been protected from rapid weathering by virtue of not being buried.

I don’t have enough knowledge to judge the work of Eggler et al., and could find no help in the form of more recent work. Their “Trail Creek” granite is no longer recognized, having been replaced with the provisional "Virginia Dale ring-dike complex" to the south in Colorado. North of the state line the facies, if it is real, is now nameless.

And so we end with the Crow tors almost as mysterious as they were when I started this series. If you-the-reader can offer additional information or ideas, they would be much-appreciated! For now ... let's enjoy the tor landscapes of the southern Laramie Range.

Our most famous tors are those of Vedauwoo, a popular recreation area not far from Cheyenne, Laramie and Fort Collins. At 8000 feet elevation, Vedauwoo draws crowds only during the warmer months. In early December we took advantage of our mild winter (so far) and trekked the closed road into Vedauwoo Glen.

No one else was there, aside from the tor creatures ...

... we even had our choice of picnic tables.

Post Script: Whew! this has been the hardest post ever!! I need a plant fix, like the taxonomy of Mexican alcoholic beverages -- coming up next. ¡Salud!

Literature Cited

Mears, B., Jr. 1984. Advanced Geomorphology seminar, University of Wyoming; field trip and class notes.

Cunningham, F. 1969. The Crow Tors, Laramie mountains, Wyoming, USA. Zeitschrift fuer Geomorphologie 13: 56-74.

Eggler, D.H., Larson, E.E. and Bradley, W.C. 1969. Granites, grusses, and the Sherman erosion surface, southern Laramie Range, Colorado-Wyoming.

Laramie Council of Industry. 1924. Laramie and Albany County, Wyoming: the center of southern Wyoming's industrial and recreation area.

Twidale, C.R. and Vidal Romaní, J.R. 2005. Landforms and geology of granite terrain. London: Taylor & Francis Group.

Fun in the Field: identify trees with dichotomous keys

2012-01-29T17:15:00.000-07:00

I’ve been asked many times to recommend books on wildflower identification, usually “with lots of photos”. But good comprehensive useable wildflower guides for the layperson are uncommon; in fact, there may not be any. Even the best by necessity include only a subset of the flora; there always is the chance of finding something that isn’t in the book. The diversity of the plant world is the issue. While there are 800+ birds in the Golden Field Guide Birds of North America (north of Mexico), there are about 2600 plants in Wyoming alone, on the order of 6000 in California and 20,000+ in North America north of Mexico.

Andy's Mystery Plant.

Compounding the problem, characters for differentiating plant species tend to be small, or subtle to the human eye. While photos may seem the best means of identification, often it is difficult to capture key features and range of variation with photographs. There’s no getting around it -- plants can be tough to tell apart.

Los Osos Oaks on the Central Coast of California
(Quercus agrifolia, the coast live oak).

Tree identification, on the other hand, usually is a realistic goal for the layperson, at least in North America (but see NOTE at end of post). There are far fewer species to consider, and many of the distinguishing features are easy to see. Field guides to trees use several approaches to identification. The Golden Field Guide Trees of North America (600 species) organizes trees by plant family, with illustrations and distinguishing features of each family provided at the beginning of the book. After choosing a family, one browses that section making choices based on brief descriptions of diagnostic features, distribution maps and illustrations. (Don't rule out this book based on lack of photos. Illustrations often are better at capturing diagnostic features of plants, counterintuitive though it may seem.)

The Audubon Society’s Field Guide to North American Trees, Western Region (300 species, including common naturalized ones), takes an approach that is a bit more involved, but probably more successful in the end if one is willing to invest the effort (isn't that always the case though?). In the first part of the book, trees are grouped by leaf shape, or flower color, or fruit type. Photos are provided for each species to help with choice. One then looks up the chosen species in the second part of the book, where there are descriptions, line drawings and distribution maps. In the introductory section there are helpful drawings and definitions of important plant terms; becoming familier with these is a worthwhile time investment if one wants to get to know trees.

Indian Paintbrush, State Flower of
Wyoming, is partially parasitic on
other plants, including sagebrush.

Then there are dichotomous keys. The name alone is off-putting, and these keys can be overwhelming to a novice or layperson due to the unfamiliar botanical terminology. Dichotomous keys are used extensively in professional manuals, though some online resources now offer more promising and intuitive approaches (see IdentifyLife for examples). A dichotomous key leads the user through a series of choices, each with two alternatives. Each step eliminates a group of plant species, finally arriving at the correct determination (usually).

Final steps in keying out the State Flower of Wyoming, the Indian Paintbrush. From Dorn 2001.

But a dichotomous key can be a very useful tool, and does not have to be difficult. Identifying plants with dichotomous keys is much easier to understand if one actually does it ... so let’s have some fun and identify a tree!

Mystery Tree, Laramie, WY

In North America, we're fortunate to have a relatively-simple tree flora (vs. the tropics ... oh my!) as well as a neat series of guides to tree identification -- the Tree Finders, for example the Rocky Mountain Tree Finder (RMTF). These little books are easy-to-use dichotomous keys. When I taught field botany at the University of Wyoming, the first day of class each summer included a field trip on campus identifying trees with our RMTFs. I’ve used Tree Finders with kids too young to read the choices themselves. They are a good introduction to dichotomous keys, they work well in many situations (but see NOTE at end of post) and they’re fun. As a demonstration, let's identify the tree on the right.

The RMTF’s dichotomous key starts on page 10, where we are asked if this tree has “needles or scale-like leaves” OR “ordinary leaves”:

So what’s the answer? (check branch on left). Did you say "needles or scales"? That's correct, our tree does not have "ordinary leaves". Very good! Having chosen the first alternative, we now go to the Christmas-tree symbol at the bottom of the page. Here we have to decide if there are needles OR if the leaves are scale-like. Because our tree has needles (I hope you agree with my decision), we go to page 14 where at the bottom we see the needle symbol.

Here we have to decide whether the needles are bundled OR single (needles are single, see close-up below).

And so we proceed through a series of decisions, always with two alternatives (page with choices shown below after photos):

if you can easily twirl a needle between thumb and finger;

OR if you can’t twirl it because it’s flattened

Answer: Ours are easy to twirl, I tried it.

needles are four-sided and leave little bumps on the twigs when they fall;

OR needles are round or oval in cross-section

Answer: Ours are the former, see bumps on twig below.

... it’s a SPRUCE! but what kind?

if the needles are tipped with hard, sharp points, making the branches painful to squeeze;

OR if you can squeeze a branch without saying “ouch”

Answer: These needles clearly are sharp-pointed!

... it’s a COLORADO BLUE SPRUCE (Picea pungens) and we’re done!

The final page for our tree has a drawing and map, which we use to confirm that our determination is correct -- yep, looks right and its range includes the mountains of southeast Wyoming. There also are life zones symbols -- the Colorado blue spruce grows in the montane and subalpine zones, as well as on the University of Wyoming campus.

Colorado blue spruce in front of Old Main, University of Wyoming, 2012.

Old Main was the first building of the University; photo ca 1908.

The Rocky Mountain Tree Finder is just one of a series of tree finders. The Pacific Coast Tree Finder was my introduction to dichotomous keys. I bought one several years before my first botany class, and was quite happy with it. There are many “finders” by the Nature Study Guild, including guides to winter trees, desert trees, birds, tracks, ferns, intertidal life, constellations and several for flowers of various regions. I’m skeptical about the last for reasons discussed in the beginning of the post, but I haven’t given them a try so can’t say for sure. There’s little financial risk in testing a Finder as they are cheap -- generally $4.95 each. To see the complete offering, visit Nature Study Guild Publishers.

The Pacific Coast Tree Finder, a real bargain at 75¢ (1973).

[NOTE: Some groups of trees are tough to identify to species, for example the willows. Others are problematic in particular regions -- e.g. some the maples of New England, or oaks in southern Arizona. In these cases you may still get close, down to a few species. Look at the distribution maps and life zone symbols for additional clues.]

Blog Crawl Gems

2012-01-27T19:30:00.000-07:00

This Week's Treasures

SOPA, PIPA An email message arrived from Wyoming Senator Mike Enzi -- he is dropping his cosponsorship of PIPA. He thinks PIPA would have been fine of course, but is listening to the public. Also, he’s glad that Senator Reid did what Senator McConnell told him to do (amazing how easy it is to spin things into one’s preferred view of the world).

The Atavism shared a poem by Brian Turner about the joy of biking, the start of a very nice post about the joy of natural history. A watchful naturalist has the opportunity for all kinds of wonderful surprises when out and about, like a tiger beetle that requires halting a brutal hill-climb. TA made mention of Beetles in the Bush, a blog with beautiful photos of beetles, other insects, arachnids and miscellaneous creatures of interest. BiB features a recent well-illustrated post by Chris Brown about a beetle that mimics caterpillar poop! BiB author Ted C. MacRae shares his favorite photos from 2011 with anyone who wants to download them (I did ... nice batch of new wallpaper).

Hopefully one of these days I will have learned enough about bugs to admire them for more than their beauty. To right: unknown beetle on unknown Tertiary basaltic/volcanic rock, Wild Rivers Recreation Area, New Mexico (roughly 2 cm long).

At Small Things Considered, Merry writes about another amazing weblet of life -- Green Flypaper. The nodes of this weblet are flies, spiders, yeasts and bacteria ... and maybe even an antimicrobial-producing microbe. Can you connect the nodes? Hint -- these are social spiders that produce huge complex sweet-smelling webs.

Babbage of the Economist blogs about digital textbooks. This seems such a no-brainer, but some folks still think the expensive paper ones are better: “To compare passages in a text, for instance, students often skip back and forth between them. And sometimes they need to have several books open at once.” uhhh ... these folks need to try some online resources. The most obvious advantage of digital textbooks that I see (beyond price) wasn’t mentioned in the post -- ease of updating as new information becomes available. UPDATE -- Babbage put up a new post on technology in education -- digital textbooks and beyond, including gaming.

Twinkle twinkle little star ... have you wondered what they are? Earth Picture of the Day provides a dazzling time-lapse “jiggled” photo of Sirius twinkling -- actually it’s “seeing cells” that cause the twinkle. For more on twinkling, go here. String players and parents of string players -- is Suzuki's “Twinkle Twinkle Little Star” playing in your head? I found a classic example, complete with tape marking midpoint of bow and positions on fingerboard, and student very glad when the whole experience is over.

You might prefer “Twinkle Little Star”, a fine old-time fiddle tune played here by the great West Texas fiddler Homer Logan.

This week's Tip for Aging Baby Boomers comes from a paper published last week in Nature (article preview), and summarized in this week’s Economist. Autophagy -- intracellular recycling -- is super important, so ramp up autophagy and get rid of those old mitochondria rife with free radicals. The investigators found that autophagy increases with ... exercise! How about that, here’s one of the mechanisms underlying the clear benefits of exercise.

GR courtesy FBNY.

Little Bone House on the Prairie

2012-01-25T19:11:00.002-07:00

Fossil Cabin on Lincoln Highway, southeast Wyoming, USA.

In the northwest Laramie Basin, in the sagebrush grassland next to the old Lincoln Highway, is a little house made of bones -- dinosaur bones. This is not as odd as it might seem, for dinosaur bones once were abundant here. They were so common that when Samuel Williston visited the area in 1877, he reported fossilized bones beyond anything he had ever seen or heard of. He persuaded his boss, the great Yale paleontologist Othneil Charles Marsh, to move their field crews from Colorado to Wyoming Territory. Time proved Williston correct. Many tons of fossilized bone went east into prominent museums, as well as into the little house in the sagebrush grassland. Among the discoveries were 26 new dinosaur species and 45 new species of Jurassic mammals. Though much of the bone is now gone, paleontologists still work the site, occasionally making new discoveries.

Fossil collecting in the olden days, southeast Wyoming.

Courtesy Stegosaurus On-Line.

The Formation
During the late Jurassic, ca 155 to 145 million years ago, the landscape in "southeast Wyoming" was very different from the sagebrush grasslands of today. The supercontinent Laurasia had split in two, and North America was moving north through subtropical latitudes. The environment was semi-arid, with lush vegetation in swampy lowlands and along rivers, dominated by conifers, ginkgos, cycads, tree ferns and horsetails. The abundant dinosaurs probably lived in riparian zones and near wetlands. Herbivorous sauropods were common -- quadrapedal giants with long necks and tails. There were armored dinosaurs such as Stegosaurus, and bipedal carnivores such as Allosaurus. Lungfishes, frogs, turtles, lizards, pterosaurs and early mammals were present as well.

This vast lowland, perhaps as much as 1.5 million sq km (600,000 sq mi) in extent, formed when precursors of the Rocky Mountains rose to the west. Streams running off the uplands for some ten million years filled the basin with sands, silts and clays, mixed with the abundant bones of the residents. The resulting sedimentary rocks eventually would be exposed with uplift of the Rocky Mountains -- the sandstones, siltstones, mudstones and fresh-water limestones of the “uniformly variable” Morrison Formation. The Morrison often is easy to recognize, with its variegated outcrops ranging from light grey to greenish gray to red to almost purple. Multiple beds are fossiliferous, some extremely and famously so.

Variegated beds of the Morrison. Photo by Geotripper.

The Anticline

North of the bone house, the land slopes gradually up to a ridge crest several hundred feet above the highway. This is Como Bluff, a small anticline at the northern edge of the Laramie Basin. It was uplifted during the Laramide Orogeny, the mountain-building event that created much of the Rocky Mountains beginning about 80 million years ago.

Como Bluff anticline east of Medicine Bow. Courtesy Google Earth, click to view.

The Como Bluff anticline is an east-west trending ridge about ten miles long that plunges to the west; the axis (crest) meets the Lincoln Highway four miles east of the town of Medicine Bow. The anticline is highly asymmetric. The south side dips gently southward, reflected in the gradual slope behind the house. The uplift is bounded on the northwest by a high-angle reverse fault, with strata vertical to overturned in places. The asymmetry has created a sandstone hogback with exposures of the Morrison Formation on the inner face -- the backside of the ridge above the house. These are the actual bluffs of Como Bluff.

Como Bluff cross section showing hogback sloping to south and Morrison exposed
on inner face. Maximum vertical relief ca 400 ft; horizontal distance ca 4 mi.
From Mears et al. 1986, after data in Dunbar 1942.

The Discovery

In 1876, Como Bluff was the site of one of the biggest fossil finds in North America. The original discovery was made by William Harlow Reed and William Edwards Carlin, station agent and station foreman at the Union Pacific Railroad’s Como Station in Wyoming Territory. Many locals were aware of the abundant fossilized bones, but apparently Reed and Carlin knew enough to recognize their importance. They even identified some to species -- Megatherum, a giant ice age sloth. Reed and Carlin wrote a letter to Professor Marsh describing their finds; several months later Marsh received a package containing a shoulder blade and vertebra from the giant sloth. He immediately recognized both the true identity of the bones (the sauropod Brontosaurus) and the value of the material. It was at that point that he directed his field assistant Williston to make a trip to Wyoming Territory to assess the merit of the site. The story from there has been told many times -- of the Dinosaur Graveyard, the Bone Wars and the two opposing gladiators, Othneil Charles Marsh and Edward Drinker Cope (several accounts listed at end of post).

Stegosaurus cast, Geology Museum, University of Wyoming. From specimen
at the American Museum of Natural History, found near Como Bluff in1994.

Reed and Carlin continued as employees of the Union Pacific, but also worked on Marsh’s field crews. Carlin switched sides, going to work for Cope before giving up the fossil business altogether. Reed stayed with Marsh, eventually becoming a full time fossil collector. He went on to work for prominent institutions such as the Carnegie Museum of Natural History and the American Museum of Natural History. Reed was appointed Curator of the Geological Museum and Geology Instructor at the University of Wyoming, where he stayed until his death in 1915.

W.H. Reed in the Bone Room, early 1900s. Miscellaneous AHC
Collections. American Heritage Center, University of Wyoming.
Used with permission.

The House

By 1932, a steady stream of travelers was crossing Wyoming on the Lincoln Highway. Popular stops in the eastern part of the state included the old Texas Trail in Pine Bluffs, the historic Union Pacific Railroad Depot in Cheyenne, the University Museum in Laramie and the Virginian Hotel in Medicine Bow. East of Medicine Bow, homesteader Thomas Boylan had been gathering bones at Como Bluff, planning to reconstruct dinosaur skeletons along the highway as a tourist attraction. But a specialist from the University of Wyoming quashed the plans when he explained that the 5796 bones were such a mix of species that there was no hope of putting together even a single dinosaur. Instead Boylan built a house by the side of the road, a dinosaur museum called the Fossil Cabin.

Como Bluff Museum postcard, 1938. Ludwig-Svenson Studio
Collection. American Heritage Center, University of Wyoming.
Used with permission

Boylan and his wife, Grayce, did a booming business with their museum and service station, especially after Ripley’s Believe It or Not featured the “Oldest House in the World” in newspapers around the country in 1938. Their business thrived even during the Depression and World War II. The Lincoln Highway was the main east-west thoroughfare across the United States, and traffic increased steadily through the 1960s.

Lincoln Highway, from "Historic Motor Convoy Treks the Lincoln Highway."
No source given.

Then in 1970, Interstate Highway 80 between Laramie and Rawlins was completed, turning the Lincoln Highway into a back road. Tourist business dropped off dramatically, and Grayce Boylan finally sold the cabin in 1974. The new owners continued to operate the museum until 1992. As of 2011, the museum was closed and the property for sale. [For status updates, check with the town of Medicine Bow.]

Visiting Como Bluff and the little bone house on the prairie

Photo from wyominghistory.com.

When the weather is fine, the old Lincoln Highway (US 30) provides a peaceful and scenic alternative to Interstate 80 between Laramie and Rawlins. Como Bluff and the Fossil Cabin are north of the highway about 13 miles northwest of Rock River and 5 miles east of Medicine Bow. Although the museum is closed, visitors are welcome to inspect the building from the outside.

The Morrison Formation lies just over the hill to the north, but is not accessible from the cabin due to private ownership. For views of the famous outcrops, take Albany County Road 610, the Marshall Road, north from US 30. This turnoff is about 9 miles east of Medicine Bow and 5 miles west of Rock River, marked by a sign for the Como Bluff Fish Hatchery. Follow the gravel road north about 7 miles to where it drops into a small valley; the bluffs and distinctive Morrison Formation can be viewed west and east of the road (private ownership, stay on road).

The Morrison Formation exposed on the inner face of the hogback at Como Bluff.
Looking westerly. Photo by Tom Rhea.

More information about Como Bluff and the Fossil Cabin can found at these websites:

Medicine Bow, Wyoming: Como Bluff

WyomingHistory.com

The Builder of the “World’s Oldest Cabin”

This is my contribution to Accretionary Wedge #42.

Sources

American Heritage Center, University of Wyoming, Online Collections (used with permission).

Breithaupt, B.H. ca. 1993. Como Bluff : the dinosaur graveyard. Laramie, WY: Geological Museum, Dept. of Geology and Geophysics, University of Wyoming.

Breithaupt, B.H. 1991. Stop #1 - Como Bluff. in Sundell, Kent A., and Thomas C. Anderson. Road log volume for Rediscover the Rockies: AAPG-SEPM-EMD Rocky Mountain Section meeting, 1992. Casper, WY: Wyoming Geological Association.

Dunbar, R. O. 1942. The geology of Como Bluff anticline, Albany-Carbon counties, Wyoming. Thesis (M.A.)--University of Wyoming.

Mears, B., Jr., Eckerle, W.P., Gilmer, D.R., Gubbels, T.L. Huckleberry, G.A., Marriott, H.J., Schmidt, K.J., and Yose, L.A. 1986. A geologic tour of Wyoming from Laramie to Lander, Jackson and Rock Springs. Public Information Circular No. 27. Laramie, WY: Wyoming Geologic Survey.

About the Bone Wars:

Schuchert, C., and LeVene, C.M. 1940. O.C.Marsh, Pioneer in Paleontology. Yale University Press, New Haven.

Shur, E. 1974. The Fossil Feud. Exposition Press, NY.

Ostrom, J,H., and McIntosh, J.S. 1966. Marsh's Dinosaurs: The Collections from Como Bluff. Yale University Press, New Haven.

Topographic reversal, then and now

2012-01-21T17:15:00.000-07:00

The southern Laramie Basin, Wyoming, USA. Click to view prominent geomorphic features.

Crossing the southern Laramie Basin are elongate mesa-like surfaces that stand as much as 500 ft (150 m) above the Laramie River. They are capped with water-worn gravels and cobbles derived from formations in the Medicine Bow Mountains to the west, with fragment size decreasing from west to east.

Above, cobbles on the Eagle Rock surface.

Below, closer view with penny for scale.

These surfaces are the remains of old drainage bottoms of the Laramie River and its tributaries. Why are former lowlands now standing above everything else? Because the rest of the old landscape is missing, removed by several-million-years-worth of erosion. The coarser deposits of the old drainage bottoms provided protective caps while surrounding softer Mesozoic rocks were worn away. This differential erosion has produced topographic reversal or inversion.

Southern Laramie Basin showing Pleistocene terraces, benches and deflation features.

View looking west. Mears 1984; illustration by Anne C. Mears.

The most prominent of the surfaces is the Airport surface, which consists of two arms that join at the Laramie Airport. The north arm extends 17 miles west to the valley of the Little Laramie River; this is the route of US Highway 130, the Snowy Range Road. The surface drops 270 ft (80 m) in elevation from west to east, with the gradient decreasing from 60 ft/mi to 20 ft/mi en route.

Two arms of Airport Surface join at Brees Field; Big Hollow in between. Click to view.

Excavation of the Laramie Basin is attributed largely to wind (deflation), in part because aeolian features are so abundant. Between the the two arms of the Airport surface lies the Big Hollow, one of the largest deflation depressions in the United States. It is roughy eleven miles in length, up to four miles across and as much as 200 feet deep (18 km by 4 km; to 60 m deep). No evidence of faulting or subsidence has been found. Deflation mainly during cold dry Pleistocene times is the generally-accepted explanation, probably aided by periglacial weathering.

Looking east towards the Laramie Range from the Eagle Rocks surface. The Big Hollow
is just beyond in the midground; the Airport surface forms the north rim of the Hollow.

Plains lakes and salt pans in Laramie Basin (click to view).

Smaller deflation hollows are common in the southern Laramie Basin; some are younger Holocene features that are still growing. Many are occupied by lakes with no external drainage, and salt pans have developed with seasonal evaporation. Aeolian deposits of salt often occur downwind of the lakes, marked by halophytic (salt-tolerant) vegetation.

The Pleistocene may be over, but aeolian processes are still with us. We've had day after day of “strong winds” with average speeds of 35 to 45 mph and gusts to 50, 60 and even 80. Topographic reversal is happening! Most of the snow has blown away, leaving relic features that were protected from deflation by compaction. Depressions made by feet and tires now "stand high" above the dirt and asphalt.

Snow deflated from dirt road, except for bike tracks
protected by compaction. Original depressions
still visible in snow patch in foreground.

Topographic reversal leaves artwork on street.

Sources

Knight, S.H. 1990. Illustrated geologic history of the Medicine Bow Mountains and adjacent areas, Wyoming. Memoir 4. Laramie: Geological Survey of Wyoming.

Mears, B., Jr. 1987. Late Pleistocene periglacial wedges sites in Wyoming; an illustrated compendium. Memoir 3. Laramie: Geological Survey of Wyoming.

Mears, B., Jr. 1984. Advanced Geomorphology seminar, University of Wyoming; field trip and class notes.

Aerial photos courtesy ArcGIS online.

Blog Crawl Gems

2012-01-19T00:01:00.000-07:00

This Week's Treasures

On the subject of internet freedom -- SOPA and PIPA are losing sponsors. Three more had dropped out as of 10 am PT Jan 18. But that’s only 3 of 31! (Map of SOPA sponsors by state) You can easily email these folks as well as your own legislators at websites for the Senate and House. Some Senate websites were experiencing technical difficulties today ... hmmm, too much traffic? Another option is to sign Google's online petition. As of 4:30 pm ET Jan 18 there were 4.5 million signatories.

For something more relaxing -- Looking for Detachment provides a series of virtual visits to Spencer Hot Springs in Nevada: then, and now a bit more civilized (for better or for worse?). On the left is the remains of a photo from waayy back, early 1980s at the latest. The memorable bath house is now gone.

Have a look at the incredible blue color of sodalite, courtesy Sandatlas. I find it so beautiful that it is almost intoxicating. Is it possible to have pleasure receptors sensitive to a specific wavelength of light?

Courtesy USGS Tapestry.

earth-literally is posting material from his course on Basin Analysis ... very cool! thanks, e-l. He starts with introductory material: “Introduction and genetic basin classification; Heat flow and the geotherm; isostasy. Introduction to stretching.” Week 2 features “More of lithospheric stretching, including passive margins”. For me, the material ranges from very informative to incomprehensible, with the latter not standing in the way of learning quite a lot about basins. I look forward to intermontane basins (my home), and hopefully metamorphic core complexes (vacationing in Basin and Range country this spring).

CHIMERAS writes about promising gene therapy to deal with the mutation behind Duchenne's muscular dystrophy in “Introns, exons, and stop codons: how antisense oligonucleotides can fix frameshift mutations”. Not only is it good news, it is a really cool mechanism -- a molecular “bandage” that covers up the error so that the resulting messenger RNA works as it is supposed to ... to direct synthesis of the protein dystrophin, critical to muscle function.

I have an amazing friend who pedals across large stretches of the US each summer for JettRide, leading packs of teens on bikes to raise money to fight Duchenne's muscular dystrophy. Go Melissa!!

Mention of proteomics generally makes me sigh and drift off, but at Small Things Considered I found a very understandable and interesting (i.e. well-written) post about the thermodynamics of proteins in the human body: "Pushing the Thermodynamic Envelope into the Proteomic Edge." We indeed are living on the edge, “just a few kcal mol^-1 away from being a pile of unfolded proteins”, a melted mass of mush.

Finally, here’s a much lighter side of molecular biology -- protein synthesis a la The Sixties, portrayed in “a dynamic and joyful way”. Actually it was 1971 at Stanford University. Paul Berg (Nobel Prize 1980) starts with a short lecture, explaining that “Only rarely is there an opportunity to participate in a molecular happening. You are going to have that opportunity” His talk is followed by Stanford students dancing on a grassy field -- messenger RNAs, ribosomal RNAs, transfer RNAs, initiation factors and amino acids all joyfully cavorting in the California sunshine. Berg later said that when he saw the entire film, he was taken aback by how dry and academic his performance was ... especially compared to what followed :)

me too -- stop SOPA, PIPA

2012-01-18T00:01:00.000-07:00

January 18, 2012, 12 AM: In the Company of Plants and Rocks has gone dark* for 24 hours to protest SOPA and PIPA -- corporate attempts to control online information for profit. See “Stop Sopa or the web really will go dark” in The Guardian. US citizens ... write your Senators (PIPA) and Congress-people (SOPA). Update: just found this well-written post by Babbage (The Economist).

*Well ... not totally dark ... I’m too new at this to wanna mess with my template.

Reading Sam McGee

2012-01-17T06:00:00.000-07:00

It’s winter in Wyoming and the days are short and cold. Sometimes when I open the door of the woodstove and feel the wonderful warmth of the fire on my face ... I feel like crawling in! I'm always reminded of Yukon gold miner Sam McGee, smiling in his crematorium on Lake LeBarge:

And there sat Sam, looking cool and calm, in the heart of the furnace roar;

And he wore a smile you could see a mile, and he said: "Please close that door.

It's fine in here, but I greatly fear you'll let in the cold and storm —

Since I left Plumtree, down in Tennessee, it's the first time I've been warm."

The Cremation of Sam McGee by Robert Service is one of my favorite poems. I love its rhyme and rhythm, the vivid imagery and ironic humor. I particularly like this reading by Urgelt, in what appears to be a cabin in the Far North with enough vitamins and herbs on the window sill to last the winter.

You can hear Robert Service himself read The Cremation of Sam McGee. His style is quite different ... does it provide insight as to the message and images he was trying to convey? Or is it a comment on the times?

This reading by Johnny Cash was National Public Radio’s song of the day on May 9, 2006. It is part of a collection of private informal recordings made in 1973, but not discovered until after his death in 2003. “Personal File” is a 2-CD set containing the 49 tracks, released in 2006.

There actually was a Sam McGee in the Yukon. While Service was living in Whitehorse, he saw the name “Sam McGee” and contacted the owner about using it in a poem. McGee agreed but later regretted his decision. When Service’s poem was published in 1907 in the collection The Songs of the Sourdough, it quickly became popular and McGee became the subject of jokes. In 1909 McGee left the Yukon for points south, looking for work. When he returned 20 years later, he found that urns containing “the ashes of Sam McGee” were being sold to tourists.

There is a "Lake LeBarge" as well -- actually Lake LaBerge on the Yukon River north of Whitehorse. Here the river channel is quite wide, forming a lake over 50 km long and notorious for harsh, fast-changing weather. Map to right courtesy Yukon: Larger than Life; click to view.

Boat on shore of Lake LaBerge, 1900.

Courtesy Yukon Archives Anton Vogee fonds, #129. Used with permission.

Camp on Lake Laberge, 1922. Claude Tidd cooks over an open fire.
Tidd served with the Royal Canadian Mounted Police, and was an

amateur musician, writer, filmmaker and photographer.

Courtesy Yukon Archives Claude & Mary Tidd fonds, #7757. Used with permission.

Finally, here are a few annotated excerpts from an illustrated version by John Severin, from the American humor magazine CRACKED (1961, #19):

The Narrator peeks in, only to find ...

... Sam smiling in his boiler-crematorium on Lake LeBarge.

You can read The Cremation of Sam McGee at the American Verse Project.

Scoria and cinders at Lunar Crater volcanic field

2012-01-15T17:15:00.000-07:00

Lunar Crater volcanic field in Nevada, USA.

It is looking like a scoriaceous week. Sandatlas wrote about Scoria from Etna, clarifying relationships among scoria, cinders and pumice. Then Earth Picture of the Day featured a beautiful cinder cone from northern Arizona, with a closeup of scoria/cinders. I feel I have to contribute too.

Lunar Crater volcanic field trends SSW across photo (all aerials from ArcGIS online).

Several years ago I visited the Lunar Crater volcanic field in central Nevada. The number of volcanic features is amazing: “approximately 95 late Pliocene and Pleistocene vents and at least 35 associated lava flows ... Vents include cinder cones, elongate fissures, and at least two maars.” The field itself sits in an older volcanic feature -- the 25-million-year-old Lunar Lake Caldera. For more information on the geology of the field, see the USGS Nevada Volcanoes and Volcanics website.

Easy Chair Crater also has an informative web page, courtesy of the University of Nevada, Reno. To the left, Sparky considers the Easy Chair cinder cone ... definitely not as nice as the couch at home.

There isn't much soil development on scoria but some hardier plants get established even so.

Lunar Crater is thought to be a maar, a flat-bottomed crater created by explosive eruption resulting from contact between super-hot magma and groundwater.

Looking across Lunar Crater from the highpoint of the rim.

The Lunar Crater volcanic field is about halfway between Ely and Tonopah, along US Highway 6. Many of the features can be viewed from gravel and dirt roads, and hiking is always an option (public land managed by the BLM).

Sparky contemplates our humble existence on Earth.

Blog Crawl Gems

2012-01-14T08:09:00.000-07:00

This Week's Treasures

In an earlier BCG post, I mentioned Yeti crabs living around underwater hydrothermal vents associated with seafloor spreading ridges, and how they raise bacteria for food. They've been getting a lot of attention recently, for example in Under the Sea Near Antarctica, 'a Riot of Life' Discovered in Super-Heated Water on the January 4 PBS Newshour:

"The most striking feature was just hordes of these crabs called yeti crabs that have sort of hairy chests and hairy arms that they grow bacteria on ... It's remarkable that we can be in the 21st century and still not know fundamental things about what lives on our planet."

The Artful Amoeba posted about the diversity of biota and ecological communities of the various ridge systems in When You Think "Hydrothermal Vents", You Shouldn't Think "Tube Worms". The habitats and inhabitants vary, as we're discovering.

At the same time that research on seafloor vent communities is ramping up, these habitats are being explored by mining companies. Fluids that rise up through vents can be mineral-rich, and when they contact sea water and cool, precipitates form -- including high-grade massive sulphides with concentrations of metals such as copper, gold, zinc and silver. For more, see “The unplumbed riches of the deep” in The Economist (source of map above).

Weathered rhyolite tuff.

Newly-discovered resources for geotripping! The latest post at the Utah Geological Survey blog announced the January 2012 issue of Survey Notes, a downloadable PDF. In it I found a neat article on the Honeycombs in Juab County, part of their “Geosights” series. I checked Geosights in previous issues via the archives, and found all kinds of neat places to visit -- with explanations, maps, photos, how-to-get-there's, etc.

The Ocelloid provides a rather mind-blowing post on evolution ... how one microbial thief consumed another only to be consumed by another thief which then had some of its organelles stolen ... all in the interest of gaining photosynthetic apparati that once belonged to cyanobacteria. Another version at Skeptic Wonder gives a nice summary of the overall plot:

“Dinophysis ingests plastids from the ciliate Myrionecta, who in turn stole them from a cryptomonad. Who, if you recall, obtained it a long time ago as a red algal endosymbiont. Who, of course, obtained the original plastid as a cyanobacterial symbiont. I think it ends there though. That poor cyanobacterial genome has been through a lot!” Click on diagram to see some “major plastid hoarding events” in the evolution of life.

My EPOD choice for the week is Crescent Moon, Earthshine and Venus, a terrific photo. Even better, thanks to the nifty diagram I now truly understand how it is that we can sometimes see the Dark Side of the Moon, illuminated by reflected light from Earth.

Two posts on blogging and writing caught my attention. Sandatlas solicits suggestions for making his posts about sand derived from metamorphic rocks more appealing. This raises the issue of why we blog, and how much if at all we should worry about our readership. The Comments are interesting; perhaps you would like to add something yourself.

Samuel Johnson, the dictionary maker.

Johnson at The Economist blogs about commas, specifically the “dreaded comma splice”. I struggle with commas. I think I use too many and have made an effort to reduce my dependence on them. Turns out comma splices are not something I use, as I realized once I figured out what the beast is. But this is an entertaining post even so. The Economist used to offer an online Style Guide, they say it will be back soon. (Sorry, I had to include one dreaded comma splice in this post.) In the meantime, we can browse the Johnson blog for edification.

Finally, January 6 was the 100th anniversary of Alfred Wegener’s lecture presenting his theory of continental drift. You probably have come across a post or two about it, and of course the Alfred Wegener Song by The Amoeba People. In case you haven’t ...

Not your typical plant photos ... nor plant photographer

2012-01-12T19:13:00.000-07:00

Danny at 17, on his way to victory.

Today’s post is about rodeo cowboy, PhD candidate, and photographer Danny Mullendore from Jackson Hole, Wyoming. By age 17 he had won his second bull riding belt buckle, which he later “buried with my Grandpa so he can rodeo in heaven.” Now "some years" later, he is dedicating his life to pursuing a PhD in botany and photographing plants.

Danny and his art are featured this week at The Sparrow Moon, a blog about art, craft and daily life. He photographs the “hidden landscapes” of dye-stained plant tissues viewed through a microscope. Dyes accentuate the cell-wall features of different cell types resulting in striking colors and patterns -- “photo abstracts” in the words of Daniel Mosquin of Botany Photo of the Day.

Crystal Creek Stream Bed is Danny's current favorite (single layer of parenchyma cells).

I especially like the color and cell-shape patterns in Time-lapse of Salmon Run.

For more micrographs and information, check out Danny Mullendore on Etsy. Best wishes, Danny, in all your current and future adventures. We miss you!

The Accordion Rocks

2012-01-11T18:29:00.000-07:00

Accordion Rocks?

Chances are you were expecting a post about rocks, perhaps even some spectacular folds, like the bellows of a squeezebox. But no, this is indeed a post about ...

the Accordion! -- it Rocks!!

Hollis and Cedar play in the kitchen.
Sparky abandons dropped-food patrol and flees.

It appears we're in the midst of an

Accordion Revival!

Hollis plays in the kitchen. Lynn, obsessed,

starts dancing madly. She can’t help herself!

Sparky has been through this before.

The Darn Accordions Marching Orchestra prepares
for the University of Wyoming Homecoming Parade.

The parade starts off with big smiles and lively music.

At 1.5 miles the Orchestra is starting to tire,
but bucks up and plays to the end of the parade route.

Pleistocene Relics in the Black Hills

2012-01-10T17:27:00.001-07:00

Black Hills of South Dakota and Wyoming, USA.

Tucked away in the Black Hills of western South Dakota and northeast Wyoming are refugia -- safe havens -- for boreal plants that have managed to hang on since the Pleistocene when the boreal zone extended much further south. Today they inhabit the shadiest coolest spots, often growing on steep north-facing slopes under heavy tree and shrub cover. Finding them is not easy.

Much of the Black Hills is forested with ponderosa pine and the flora has strong affinities with the Rocky Mountains, but the cool shady gulches of the northern Hills are different. Here one finds forests of white spruce and paper birch, more like the Great Lakes region, New England and Canada to the north. There often are many boreal species in these gulches, part of the diverse flora that makes the Black Hills famous as a "botanical crossroads".

Distribution maps for white spruce, paper birch. Note disjunct occurrences in Black Hills

in western South Dakota, northeast Wyoming. All maps from Flora of North America.

Ground pine, Lycopodium annotinum. Courtesy Jerzy Opioła.

Ground cedar, L. complanatum (= Diphasiastrum complanatum).
Courtesy Craig Althen.

Among the boreal plants in the Hills are three species of club moss or Lycopodium: ground pine, ground cedar and tree club moss. These are not true mosses but rather “fern allies”. They are vascular plants, i.e. with a well-developed vascular system which the true mosses lack. Like ferns they reproduce by spores, rather than by seeds as do “higher” plants.

The “fern allies” are actually a hodgepodge of plant groups, lumped together in the past because relationships among them weren’t clear. Most current phylogenies split the former allies into two major groups: the Lycophytes and the Euphyllophytes. The first group contains the club mosses; the second includes true ferns, horsetails and whisk ferns, as well as seed plants, which split off from the rest more recently.

Phylogeny of vascular plants. Click to view. Modified version of this diagram.

The scientific name for the club moss genus, Lycopodium, means wolf’s claw, a very old name referring to the shape of the roots. Club moss is used sometimes used as a homeopathic remedy in spite of its known irritation to mucous membranes. The oils of the spores of some species are highly flammable, do much so that these club mosses were used in the past as flash powder for photography and stage lighting! (Reader’s Digest 1997). Drawing below courtesy U. Minnesota Extension Service.

Note re scale: the three club mosses in this post are less than 30 cm (12 in) tall.

Tree club moss, L. dendroideum.
Courtesy Kirisame.

Some boreal species, such as white spruce and paper birch, are fairly common in the Black Hills in the right habitat. In contrast, the three club mosses occur only as widely-scattered small populations, and are managed as species of concern on Black Hills National Forest.

Distribution of Black Hills club mosses.

Patches thinks that if she waits long enough, the little boreal plants will reveal themselves.

Literature Cited

Reader’s Digest. 1997. Magic and medicine of plants. Reader’s Digest Association, Inc. [Recommended -- interesting, entertaining, and I especially like the carefully written “statements regarding the scientific evidence about the validity of the uses in folk medicine” for each species covered.]

Creatures of Stone II -- genesis

2012-01-08T07:02:00.000-07:00

Tors of the southern Laramie Range, Wyoming, USA.

Many times I have driven home at sunset after wandering in the Laramie Range east of town. At dusk the creatures of stone that reside on the broad summit stand silhouetted against the evening sky, a remarkable view of giants forever waiting by their castles, somehow life-like but never moving. If during the light of day you go to look more closely, these creatures disappear no matter how carefully you sneak up on them. In their place you will find piles of boulders, or perhaps carefully-stacked stones.

These are tors -- masses of granite standing above the surrounding landscape. About a month ago I provided an introductory tour of tors. Now we consider how they may have come to be.

In perhaps the earliest study of tors, Borlase (1754) concluded that the Cornwall tors of southwest England were man-made monuments similar to Stonehenge. Other investigators arrived the same conclusions elsewhere in England. The fact that many of these outcrops were composed of roughly cube-shaped stones lent credence to the theory, for it was assumed that the makers of Stonehenge were Druids and that Druids worshiped Mercury, symbolized by the cube. [In reality, almost nothing is known about Druid culture: “They left no written accounts about themselves and the only evidence is a few descriptions left by Greek and Roman authors, and stories created by later medieval Irish writers.”] Borlese's treatise can be viewed in its entirety here.

Sea stacks, by Sam Abell. Courtesy National Geographic.

By the early 1800s cultural explanations were being replaced with geological theories. One of the first proposed that tors were relics of ancient coastlines, based on their similarity to sea stacks. In the late 1800s reports of tors from arid environments led to the idea that tors were sculpted by wind, a theory that had strong support as late as the 1940s.

Tors at Vedauwoo.

In 1955 David Linton published an influential paper arguing that tors develop in two stages: subsurface weathering first creates the shapes, erosion later exposes them. The idea had been proposed more than fifty years prior but was ignored; in contrast, Linton’s publication attracted wide interest. Now there is general agreement that much or even most of the work on a tor sculpture is done underground, where it remains hidden until exposed by erosion, perhaps millions of years later.

Two-stage process of tor formation; click to view.

Fracturing is the first step in sculpting a tor. While granite is indeed a very hard rock, fractures and fissures in bedrock are common, especially near the land surface. Fractures can be dense or widely-spaced. Typically there is a system of orthogonal (at right angles) fractures -- clearly seen in blocky tors -- as well as other seemingly-random fractures, resulting in a complex set of cracks (Twidale and Vidal Romaní 2005). These are the gateways leading to weathering. Ground water percolates through soil, collects in cracks and proceeds to attack the bedrock through chemical weathering.

With enough time a mantle of rotted granite -- the regolith -- develops over the bedrock and below the surface soil. The boundary between regolith and fresh rock is the weathering front. In areas underlain by granite, the weathering front typically is a sharp boundary or narrow transition zone. The regolith above the weathering front can be quite thick -- as much as several hundred meters in warm humid environments. In addition to playing a role in soil development, the regolith holds water and contributes to weathering of the underlying granite (Twidale and Vidal Romaní 2005).

Granite corestones in grus. Courtesy Banco de Imágenes Geológicas.

Rotted granite or “grus” also fills fractures in bedrock. With enough weathering, the result is solid boulders set in a matrix of rotted granite -- corestones in grus. “Corestone” originated with quarrymen in England, referring to the intact boulders surrounded by decomposed granite that they found in quarries.

Grus around developing corestones. From webmouser.org.

But not all bedrock is eroded into corestones. Degree of weathering varies with depth, with deeper rock experiencing less (shown in diagram above). This can be seen in the tor on the right, which is less fractured and weathered below, and topped by boulders (note fallen ones at base).

Weathering is only half the process of tor creation. In the second stage erosion exposes tors and boulders. Again water is the likely agent -- generally running water but occasionally other things such as wave action. The regolith and grus in fractures are washed away relatively quickly, whereas the fresh rock of corestones and tors is much more resistant to weathering, especially once it is free of moisture-laden cover.

Scenarios leading to erosion vary from location to location. Often uplift resulting in rejuvenated streams and increased erosion is the suspected cause. (Part 3 in this series will discuss possible reasons for accelerated erosion.) Removal of regolith is quite rapid geologically-speaking. “In the Cairngorms [Scotland], tors can emerge at rates of ca 30 mm/ka” [0.12 in per century] (Phillips et al. 2006).

Haytor (Hay Tor) in the Cairngorm Mountains, Scotland. Courtesy Smalljim.

Fracturing and weathering of granite bedrock starts long before tors ever see the light of day. Linton (1955) suggested that in the case of the Dartmoor tors in southwest England, much of the underground weathering took place in warmer wetter times. Certainly more humid environments have greater rates of bedrock weathering. Linton argued that the latest possible date of profound weathering was the last interglacial, and suggested that it may have been much earlier -- perhaps during Pliocene times (5-2.5 my bp) when England was a warm and humid place. More recently, other workers also have interpreted tors as indicators of warmer past climates when subsurface weathering was more agressive (see climatic zonality in Twidale and Vidal Romaní 2005, pp 309-313).

Fur Tor on Dartmoor, southwest England. Courtesy Dartmoor Walks.

The two-stage process explains how tors form, but the story is not complete, there is another question: Why are there only isolated clusters of tors? Why are tors not found all across landscapes underlain by granite? But sorry -- this post has gone on long enough. You will have to wait for Part 3 -- the story of the Crow Tors of the Laramie Range in southeast Wyoming.

A stunted aspen and a tiny tor dance together on the summit of the Laramie Range.

NOTE: “Tor” is not used by all geomorphologists. For example, Twidale and Vidal Romaní (2005) classify granite landforms with no mention of “tor”. Their classification includes several tor-like forms: bornhardts are massive domal structures; castle koppies are more dissected, fractured masses; nubbins are mounds covered with boulders; and boulders are ... boulders, sometimes very large.

Literature Cited

Borlase, W. 1754. Observations on the antiquities historical and monumental of the County of Cornwall consisting of several essays on the inhabitants, druid superstition, customs, and remains of the most remote antiquity in Britain and the british isles : exemplify'd and prov'd by monuments now exstant in Cornwall and the Scilly islands... Available at http://bibnum.univ-rennes2.fr/items/show/35?image=6&v=#bibnum

Linton, D.L. 1955. The problem of tors. The Geographical Journal 121:470-481. First page can be accessed free here.

Phillips, W.A., Hall, A.M., Mottram, R., Fifield, L.K., and Sugden, D.E. 2006. Cosmogenic ¹⁰Be and ²⁶Al exposure ages of tors and erratics, Cairngorm Mountains, Scotland: Timescales for the development of a classic landscape of selective linear glacial erosion. Geomorphology 73:222-245.

Twidale, C.R. and Vidal Romaní, J.R. 2005. Landforms and geology of granite terrain. London: Taylor & Francis Group.

Blog Crawl Gems

2012-01-05T07:00:00.000-07:00

This Week's Treasures

If you’ve recovered sufficiently from the New Year’s carousing, you might enjoy the Botany and Spirits series that finished up last week at Botany Photo of the Day, including juniper (gin), sugar cane (rum), agave (tequila), hawthorne (a vodka flavoring) and especially interesting: Baudoinia compniacensis, the angels' share fungus, which lives on the “angels’ share” of whiskey and other distilled products -- the part that is lost to evaporation during aging in wooden barrels. Though common and widespread, angels’ share fungus was properly named only recently, following detective work to explain the black mold that was coating neighborhoods near Hiram Walker warehouses. The story is told in detail in The Mystery of the Canadian Whiskey Fungus.

Thanks to Ron Schott of Geology Home Companion for pointing me to What are the roots of geobotany? and the Utah Geological Survey blog. He correctly guessed that a post on plants and rocks would interest me :)

Next, an article from Scientific American on some of the neat things to watch for in the sky in the year to come. Joe Rao presents “The top 12 "skylights" for this coming year including a "double planet" in May and a Venus transit of the sun in June.” This is a handy list for someone who loves to see cool astronomy things but is never able to keep track of what’s happening on a regular basis. But I already slept through the first one -- Quadrantid meteor shower Wednesday morning before dawn.

Another great Earth Picture of the Day: Brocken Spectre and Glory from Northern Italy. Brocken is where the phenomenon supposedly was first reported -- the high point of the Harz Mountains in northern Germany. This peak seems to have lots of mystical properties and phenomena associated with it, so it's not surprising that spectres were found there. As Goethe wrote in 1808:

Now to the Brocken the witches ride;
The stubble is gold and the corn is green;
There is the carnival crew to be seen,

And Squire Urianus will come to preside.
So over the valleys our company floats,

With witches a-farting on stinking old goats.

Click to see witches flying around the Brocken in this illustration
by draftsman L. S. von Bestehorn (1732; public domain).

There are more EPODs of Brocken Spectre and Glory here and here. Many different optical effects are explained at Atmospheric Optics, a pretty neat web site that I stumbled upon. Maybe one day I will encounter my shadow as a Brocken Spectre with a halo of Glory, that would be so cool!

Finally another tip for aging baby boomers to stay ahead of the grim reaper -- get up from that computer, sitting is killing you! followed by No Really - Sitting is Killing You (some readers were skeptical).

GR courtesy FBNY.

My New Year's Resolutions

2012-01-03T17:15:00.000-07:00

For more information, see Jonah Lehrer's 2009 end-of-the-year essay explaining why "New Year's resolutions are exactly the wrong way to change our behavior."

Plants and Rocks: columbines and granite

2012-01-01T20:00:00.000-07:00

Laramie columbine on Laramie granite. Upside-down US dime is 1.9 cm (0.75 in) across.

In the summer of 1887, 28-year-old Aven Nelson left Iowa for Laramie City in Wyoming Territory, having been hired as Professor of English at the new University of Wyoming. When all six faculty members had arrived, University President J. W. Hoyt realized there was a problem -- he had mistakenly hired two English professors. While Nelson had a Bachelor of Arts and Didactics degree from the State Normal School in Kirkville, Iowa, the other guy -- W. I. Smith -- had a Master’s Degree in English from Dartmouth College, and got the job.

Old Main, the first building at the University of Wyoming, was completed September 1, 1887, just in time for classes. (This photo was taken in 1908).

Biography of Aven Nelson (Williams 1984).

Hoyt interviewed Nelson to see what other subjects he might be qualified to teach. Nelson explained his love of natural history, his excursions in search of wildflowers, and the six lectures on plants he had attended at the Normal School in Iowa -- this was enough to justify appointment as Professor of Biology at the new university. From that strange beginning, Aven Nelson went on to become the preeminent botanist of the Rocky Mountain region for many years. He started the Rocky Mountain Herbarium, now recognized as one of the major collections in the United States, and in his 55-year career described numerous new plant species. Perhaps his most important contribution was as teacher, as many of his students went on to become eminent botanists themselves.

In 1894 Nelson began a systematic survey of Wyoming plants. He spent two months in the field, traveling on horseback with a hired guide and outfitter. They went by way of Douglas, Casper, Lander, Jackson Hole, Green River, South Pass, and Bates Hole, camping out most of the time. Nelson reported that they had a tent along but rarely used it, the weather being fine for sleeping under the stars. By the end of the field season he had collected 1,200 specimens, which he explained would have been impossible without the help of his diligent student assistant.

Nelson's collecting areas, 1894 and 1895 (Nelson 1896; click to view).

The next field season consisted of several shorter expeditions, including one to the rugged northern Laramie Range in early August. One objective was to climb Laramie Peak, which at 10,276 feet elevation (3132 m) stands significantly higher than the rest of the range. The party approached the peak from the east, following the Cottonwood Creek drainage to “the foot of Laramie Peak”. On August 4, Nelson found a small columbine growing “in a canon where it occupied the dry crevices in abrupt cliffs”. They went on to climb Laramie Peak the next day, and returned home with 117 collections; the total for the season was 670.

Laramie Peak viewed from south. DT Horning photo.

In 1896 Nelson published the First report on the Flora of Wyoming, including a list of the 1176 known plants of the state (today’s flora is estimated at 2800). He made it clear that much more work remained to be done. Nelson also described four new species and eleven new varieties, a major achievement for a botanist still early in his career. The columbine from Cottonwood Canyon was one of the new species, formally named Aquilegia laramiensis -- Laramie columbine.

Rugged country in the northern Laramie Range. Cottonwood Canyon, type
locality for the Laramie columbine, is behind the ridge in the foreground.
Laramie Peak is out of view to the left (west). DT Horning photo.

Like its much better known relative the Colorado columbine, the Laramie columbine has flowers with spurred petals. But the flowers are much smaller -- the spurs of the petals are only 10 mm long while those of the Colorado columbine can be up to 50 mm long. The entire plant is less than 20 cm tall. The flowers are white to pale blue.

Laramie columbine.
Illustration by Isobel Nichols.

Colorado columbine, courtesy US Forest Service.

Nelson made several more collections of the Laramie columbine in 1900 and 1901, including one from ca. 60 miles south of Laramie Peak, a major range extension. No additional locations were documented for seventy years. Starting in the 1970s, new populations were occasionally reported; by 2002 the species was known from 13 sites.

Surveys of the Laramie columbine were done in 2003, 2004 and 2009, funded by the US Forest Service and Bureau of Land Management. The species is now known from 51 sites, all in the northern Laramie Range, i.e. the Laramie columbine is endemic (restricted) to the northern part of the range (Marriott and Horning 2010). This is a case of narrow endemism as the species grows in a very limited area -- all but one of the known sites are clustered in a narrow zone approximately 55 km (32 mi) in length.

Distribution map for Laramie columbine (green dots; from Marriott and Pokorny 2006).

The Laramie columbine grows on suitable microsites on igneous and metamorphic rocks -- typically in small pockets of coarse soil in crevices, on small ledges or at the base of outcrops, and almost always where there is little or no other vegetation. Populations are small; the largest ones contain perhaps 100 individuals. So how rare is this plant? While we know that it is a narrow endemic, we still don’t know how abundant it is within its range, even after all that work. Why? Because this is the kind of country in which the Laramie columbine grows!

There is a wealth of potential habitat in this photo, and much of it is time-consuming, difficult or impossible for a field botanist to access (photo by DT Horning).

Most known populations of Laramie columbine grow on the Archean “Laramie granite” (Condie 1969, Johnson and Hills 1976) which forms the maze in the photo above. A few scattered populations have been found to the south in the central metamorphic complex -- a zone of Archean rocks metamorphosed during Proterozoic events (Patel et al. 1999). Further south where the Proterozoic Sherman granite dominates, the columbine apparently is absent; none have been found in spite of easy access and frequent collecting.

Precambrian rocks of the Laramie Range, click to view.
(from Marriott and Pokorny 2006, modified from Johnson and Hills 1976).

Laramie columbines at base of granite outcrop.
DT Horning photo.

What is it about the “Laramie granite” that makes it such good habitat for the Laramie columbine? It seems to provide the right kinds of microsites: shaded, flat to gently sloping, and with some soil development but not enough to support other vegetation. This last habitat feature is shared by many of the narrowly-endemic rare plants of Wyoming -- they grow where other plants don’t.

And what is it about the “Laramie granite” that requires putting the name in quotation marks? Alas, it is not an accepted name -- not recognized in the USGS GEOLEX database nor by recent workers (e.g. Patel et al. 1999). It was applied by Condie (1969) in a study of the petrology and geochemistry of the granite and adjacent metamorphic rocks. He described the mass of granite as the “Laramie batholith”, and suggested the best explanation for its genesis was “fractional crystallization of an intermediate or mafic magma derived by the partial melting of the lower crust or upper mantle.”

Condie’s 1969 paper elicited a quick and forceful response from Smithson and Hodge (also 1969) who argued that his conclusions were unsupportable, especially in the southern part of the study area where they themselves were working. Their main objection was insufficient time in the field: “A central question relates to how many days were spent in the field on the study. ... The area is exceptionally large (4000 km2) and complex.” Laramie columbine surveyors would agree!

Johnson and Hill (1976) sampled the northern part of the “Laramie granite” more intensively, arriving at the same conclusions as Condie but wisely making it clear that their findings should not be extrapolated beyond their study area. Patel et al. (1999) avoided controversy altogether by calling the Archean granite simply “granite” of the “Laramie Peak block”.

Recent work in the Laramie Range has focused on the more exciting Archean craton margin -- the central metamorphic complex and Proterozoic hard rocks to the south. And so the granite to the north remains officially nameless. Those of us studying the Laramie columbine continue to call its substrate the “Laramie granite” as it serves the purpose of communication. And besides ... it's only fitting that Laramie columbine should grow on Laramie granite.

Aven Nelson in the field, from UW archives.

Literature Cited

Condie, K.C. 1969. Petrology and geochemistry of the Laramie batholith and related metamorphic rocks of Precambrian age, eastern Wyoming. Geological Society of America Bulletin 80:57-82.

Johnson, R.C. and F.A. Hills. 1976. Precambrian geochronology and geology of the Boxelder Canyon area, northern Laramie Range, Wyoming. Geological Society of America Bulletin 87:809-817.

Marriott, H. and M.L. Pokorny. 2006. Aquilegia laramiensis A. Nelson (Laramie columbine): a technical conservation assessment. USDA Forest Service, Rocky Mountain Region. Available: www.fs.fed.us/r2/projects/scp/assessments/aquilegialaramiensis.pdf [accessed December 2011].

Marriott, H. and D. Horning. 2010. Results of field survey and status report update for Laramie columbine (Aquilegia laramiensis). Unpublished report prepared for the Wyoming Natural Diversity Database, University of Wyoming, and the Bureau of Land Management, Casper Field Office. Available: www.uwyo.edu/wyndd/_files/docs/reports/wynddreports/u10mar01wyus.pdf [accessed December 2011].

Nelson, A. 1896. First report on the flora of Wyoming. WY Agr. Exp. Sta. Bull. 28:78-79.

Patel, S.C., B.R. Frost, K.R. Chamberlain and G.L. Snyder. 1999. Proterozoic metamorphism and uplift history of the north-central Laramie Mountains, Wyoming, USA. J. Metam. Geol. 17:243–258.

Smithson, S.B., D.S. Hodge. 1969. Petrology and geochemistry of the Laramie batholith and related metamorphic rocks of precambrian age, eastern Wyoming: discussion. Geol. Soc. of Am. Bull. 80:2383-2384.

Williams, R. L. 1984. Aven Nelson of Wyoming. Boulder, CO: Colorado Associated University Press.

Blog Roundup -- yeee haw!!

2011-12-31T06:30:00.000-07:00

Traditional American cowboy song, paraphrased slightly.

I just learned about another blogging tradition ... the year-end roundup where folks gather the best of their own posts, most popular, etc. Being from Wyoming I don't wanna miss a roundup! but unfortunately I haven't been at it long enough to have much stock to gather.

Instead, I'm taking this opportunity to thank my compatriots of the blogosphere for a great time, and I look forward to more fun in the year to come.

Happy New Year -- Felíz Año Nuevo

from In the Company of Plants and Rocks

Happy Birthday Frank!

2011-12-30T07:49:00.000-07:00

Little Missouri Buttes and Devils Tower in northeast Wyoming, USA.
Click on photo to see F & H on top.

In 1978 Frank and Hollis hiked from the tipi in Weaver Canyon to the Little Missouri Buttes, scrambled up the highest one, and talked. That’s when they discovered that they were born ten days apart, and also when they agreed with conviction that “Blessed are those that live out their dreams.”

Blog Crawl Gems

2011-12-29T07:39:00.000-07:00

This Week's Treasures

Sandatlas has a very nice post about blogging. I have been "seriously" into it for three months and am seriously hooked, for all the reasons noted in the post: I like to write, blogging is effective practice, I learn things and it's a “great motivator”. “Is there anything bad also?” asks Sandatlas. For me that would be the “great motivator” -- blogging sucks time away from work as it is much more interesting, fun, satisfying. Since I’m self-employed working at home, I have to set limits. He goes on to encourage others to blog -- I heartily agree.

One thing I personally enjoy is seeing that people from all over the world are reading my essays! This still amazes me, and is something really wonderful about our online world.

Reading blog posts is as fun and interesting as writing them. There are soooo many fascinating things in the blogosphere! This Blog Crawl Gems series features some of my favorite posts each week.

Galileo's Pendulum convinced me that I had no idea how mirrors actually work. But now I do. Did you know that "mirrors actually don’t reverse left and right ... The mirror is actually reversing front and back!" It's true, I tried it. But that's for flat mirrors, there are concave mirrors and convex mirrors and experiments with spoons! This is a fun post.

Another neat post from The Artful Amoeba: the First Book of Photographs. Published in 1843, this book was authored by a woman (the photographer), surprising for the times. It is a collection of cyanotypes of algae, specifically British seaweed. This is one of the "old, rare or valuable" scientific books on display in the current Treasures of the Royal Society Library exhibit. Cyanotype to right is Desmarestia ligulata, Flattened Acid Kelp (courtesy the British Library).

Finally, I especially enjoyed the December 27 Earth Picture of the Day -- a "close-up" of the Horseshoe Bend, an entrenched meander on the Colorado River. Why? because it is so beautiful, and this time of year so inviting!

Horseshoe Bend southwest of Page, Arizona, USA, as viewed via Google Earth.

El Tío -- god of underground miners

2011-12-27T17:16:00.000-07:00

Underground mining is an extremely dangerous way to make a living. Thousands are killed each year, mainly in coal and hard rock mining. There are far more casualties in developing countries. China leads in coal mining fatalities, with 80% of the world’s deaths (while producing 35% of the world’s coal). An estimated 13 Chinese workers die in coal-mining accidents each day. In the US, 60 to 70 US miners die each year in all types of mining (from About.com Mining, Common Mining Accidents accessed Dec 2011).

It is estimated there have been 8 million deaths in the 500-year history of underground mining in Bolivia, mainly for silver and tin. Silver mining began with settlement by Spaniards in Potosí in 1546. In 1603 it was reported that 58,800 Indians were employed in the mines. Later 30,000 African slaves were brought in to work as well. In the late 1600s the population of Potosí was 200,000 -- one of the largest cities in the world at the time. By 1800 the silver mines had been depleted and investment and production shifted to tin. Then in 1985 the global tin market crashed.

Cerro Rico (rich hill) behind Potosí (Potosí Tourism)

Though mining no longer dominates the Bolivian economy, silver is still produced in the Potosí area, often by scavenging in old worked areas. The workforce was estimated at 9000 in 2004, including many children. It is an extremely dangerous occupation -- safety equipment is primitive at best, and dust inhalation is a major problem. The estimated life-span of a Bolivian silver miner is 40 years -- most die from silicosis. The human cost of silver mining in Bolivia was addressed in two recent documentaries: The Devil’s Miner by Independent Lens (2006) and Bolivia's Child Miners by Unreported World (2010).

Our Lady of the Tunnel

In the face of such obvious danger Bolivian miners seek spiritual protection from two sources: Nuestra Virgen del Socavón (the Virgin of the Tunnel) above ground, and el Tío (the Uncle) below ground. La Virgen appears to be descended from the Uru Mother Earth spirit, Pachamama, with a significant contribution from the Virgin Mary.

El Tío (Wari).

El Tío also is mix of indigenous beliefs and Catholicism. He is the pre-Columbian god of the mountains and underground, but has taken on characteristics of the Christian devil, mainly in appearance.

In mines there are numerous statues of el Tío and alters for offerings -- cigarettes, coca leaves, soda pop and alcohol. And now tourists are offered mine tours and visits with el Tío. These are becoming fairly popular judging by the number of posts in travel blogs. Photos to left and right courtesy Soulshine Traveler.

La Diablada in Oruru during Carnaval.

El Tío has been popularized also in la Diablada, the Devils Dance, which is thought to have originated in pre-Columbian times to appease El Tío, then known as Wari or Huari. La Diablada has become extremely popular in Bolivia -- best known are the Carnaval performances in Oruru. Recent claims to la Diablada by Peru have set off a diplomatic storm, and other Andean countries now claim it as well.

Happy Geolidays to all!

2011-12-22T17:54:00.000-07:00

The Laramie Basin in the southern Rocky Mountains (USA) is a classic Laramide syncline situated between two broad-backed Laramide uplifts: the Laramie Range to the east and the Medicine Bow Mountains to the west. Above the broad summit of the Medicine Bow Mountains stand the high quartzite ridges of the Snowy Range, and several en echelon anticlines extend into the basin (see illustration below).

Blog Crawl Gems

2011-12-22T13:41:00.002-07:00

This Week's Treasures

First, I would like to thank The Mermaid’s Tale for their post about the ethics of using chimpanzees and other animals in medical research, prompted by recommendations from the Institute of Medicine of the National Academies (USA) to sharply curtail use of chimpanzees. I have never understood how people could subject animals to the kinds of treatments that they do. One study on stress comes to mind, where mice were repeatedly shocked until they failed to respond. Without apology, the investigators published the details of their experiments along with photos of a mouse in various stages of being shocked, finally just standing in a dazed stupor.

On a cheerier note --

Rapid Uplift writes about why he teaches rugby to village kids in rural India (it’s not just for the terrific views of layered Deccan Basalts) ... go Rapid Uplift!

For another spectacular view, see Gazing at distant hills…

But wait ... note the poor exposure, and the view obviously was not well-framed. So what is so spectacular? These are distant hills on Mars, part of Endeavor Crater. I am awestruck looking at landscapes on another planet. You can do some exploring of Mars yourself courtesy Road to Endeavor: Walking alongside Opportunity as she explores Endeavour…

And some big news for aging Baby Boomers ... the pace of the Grim Reaper has been established! Now we know how fast we have to walk to evade him.
GR courtesy FBNY.

Finally ... don't miss the wonderful sand grain Christmas card from Sandatlas.

Plants and Rocks: Vegetation mosaic on Miocene marine strata ... sweet!

2011-12-18T10:59:00.000-07:00

Aerial view of Sierra Madre crest in southern California, USA.

“Man has mental limitations, and nature is infinitely complex. To deal with this situation man invents classifications. Nature does not classify trees, flowers, and rocks -- we do, so that we can deal with them in a reasonable fashion.” -- Robert P. Sharp

We vegetation ecologists are pattern-seekers and classifiers, that's our job. Based on his remarks it would be easy to think Sharp was one of us, but he was not. He was a geologist recognized for contributions in basin-and-range structure, glaciation, erosion surfaces, desert sand dunes, isotopes in snow and ice, and surface forms and processes on Mars. He served as long-time head of geological sciences at Caltech, and received the National Medal of Honor in 1989.

To his credit, Sharp had a great interest in explaining geology to lay people. His Southern California Field Guide (K/H Geology Field Guide Series, 1975) introduced me to the geology of the Transverse Ranges of southern California -- the ranges north of Santa Barbara that trend east-west in contradiction to the predominantly northwest-trending structural grain of California.

It was in the Transverse Ranges that I did my first vegetation study -- the beginnings of a career in field botany and vegetation ecology. For a class project I backpacked across the Ranges from south to north, to describe and classify vegetation, and glean some understanding of the ecology. I was young and naive, with great faith in vegetation classification and patterns in general. While I had to have read Sharp’s introductory remarks, I’m sure they did not sink in. Now, 35 years later, they seem profoundly insightful.

There is pattern in vegetation -- we sense this intuitively and acknowledge it when we talk about hardwood forests in New England, grasslands of the Great Plains or treeless alpine vegetation on mountain summits. But at a finer scale, discrete associations of plant species and correlation with specific habitats often become fuzzy or break down completely. The wraith we thought we saw may disappear when we look closely.

For my study I intended to traverse the three ranges north of Santa Barbara -- Santa Ynez Mountains, San Rafael Mountains and Sierra Madre -- and finish in the Cuyama Valley. I was a dedicated naturalist and backpacking bum (John Muir was my hero and role model) with little money, crummy gear, and of course no camera. Instead I kept a journal, and sketched some of my experiences.

The trip started via the Santa Barbara city bus system to a trailhead at the base of the Santa Ynez Mountains, which rise steeply from the narrow coastal plain. It was in these mountains that some of the earliest studies were done suggesting that the Transverse Ranges did not always have their odd east-west orientation, that they are part of a crustal block that has rotated at least 90° clockwise since early Miocene time and continues to do so (Hornafius 1985). Nicholson et al. (1994) found a possible mechanism in a partially-subducted microplate under the western Transverse Ranges (WTR) crustal block. As the Pacific and North American plates converged in early Miocene time, the intervening Farallon plate fragmented into microplates which continued to be subducted under the continental margin. But as subduction slowed and was transformed into right-lateral strike-slip (horizontal) motion, the microplate under the WTR block became attached to the Pacific plate and started moving northwest, causing the overlying block to rotate.

From Onderdonk 2007 (see literature cited at end of post).

It was a sunny day in early April, and warm walking up the south flank of the Santa Ynez Mountains. As the trail left the drainage bottom for drier habitat above, I noted a transition from Riparian Woodland dominated by sycamores to Foothill Woodland dominated by California live oaks to the dense shrubland of Hard Chaparral. I continued through chaparral to a campsite at what may have been an old homestead (pear and apple trees). The next day I hiked down into the Santa Ynez Valley where I caught a ride with some hippies as far as the “Brotherhood of the Sun” commune.

Yerba Santa, Eriodictyon californicum
Courtesy of SageHeart.

By the time I got to my next campsite, mares tails were passing overhead, followed by thick dark clouds. It rained that night “filling the air with the odor of yerba santa”, one of the many pungent plants of the chaparral.

The next two days I hiked up the south flank of the San Rafael Mountains, the highest of the three ranges. I continued to see the same patterns -- Riparian Woodland in drainage bottoms giving way to Foothill Woodland and then chaparral moving upslope into drier habitats. But there were new indicators appearing with increasing frequency -- conifers. Coulter pine and big-cone Douglas fir were the first, soon joined by white fir, sugar pine and incense cedar -- trees indicative of cooler wetter habitats at higher elevations.

California incense cedar.

Sure enough I awoke to frost, with hoarfrost needles on grass stalks and “socks washed yesterday hanging frozen on line”. Later in the day “snowflakes started to fall” and as the cover of conifers increased going up the trail, the snowfall got heavier. The trees were beautiful frosted with snow, especially the incense cedars. At the crest (5800 feet above sea level) I “bivouaced under small oaks -- rainfly with poncho as vestibule” and noted: “This seems to be a regular blizzard -- in April? No Fair!”

In the morning I was “awakened by a cheerful bird singing madly somewhere in the brush.” The sun came out as I put on my frozen pants and boots and optimistically headed off along the crest enjoying great views and majestic Douglas firs and incense cedars. I hiked down into the canyon of the Sisquoc River, reached the bottom and got my rainfly set up just before the rain and hail started. Enjoying a dinner of cookies I wrote “April showers bring May flowers. This is a welcome storm even though it makes backpacking a little unpleasant.”

Continuing down the Sisquoc the next day I reached the Sisquoc Falls, spectacular in this dry country -- “3 or 4 large falls in a row, the largest 50-75 feet high” -- but by then it had been raining and hailing for an hour so I kept going. That evening I noted: “It would be nice to have one or two dry days to end the trip.”

The next day the rain finally stopped and my mood was high going up the south flank of the Sierra Madre, the last of range of my traverse. It would be a long but gentle hike to my campsite once I reached the crest. I saw several single-needle pinyons and then junipers soon after -- this was the beginning of pinyon-juniper woodland, a much drier vegetation type here in the rain shadow of the San Rafael Mountains.

At the summit was a fine example of a deterministic relationship between bedrock and vegetation. Much of the Sierra Madre crest is underlain by the Miocene Branch Canyon and Monterey Formations -- a mix of nearshore and beach sandstones, and marine shales and mudstones. I saw that the vegetation on the crest was a mosaic of grassland and hard chaparral, clearly correlated with changes in bedrock ... sweet!

Santa Barbara Potrero on crest of Sierra Madre.

Areas underlain by sandstone supported chaparral dominated by scrub oak (Quercus dumosa) and bearbrush (Garrya fremontii). The intervening areas of Monterey shales and mudstones were covered with grassland, including huge potreros (Spanish for field or pasture but used here for large grassy openings in the chaparral). The explanation was straight-forward. Fine soils derived from shales retain moisture near the surface and shallow-rooted grasses thrive. Rockier sites support shrubs that send roots down cracks in the sandstone to trapped water.

Scanning electron micrograph of clay.
Clay particles have high surface area relative
to their small size. Water adheres easily,
giving clay its absorptive properties.

Fascinating as this was, I came hate the grasslands. Whenever the dirt road crossed grassland it was unbelievably gooey after four days of rain and snow. I observed: “grassland means clay soil which means slippery -- road is impossible to walk on.” In contrast “in areas where scrub [oak and bearbrush] is present, the soil is rockier and better drained, and one can easily walk on the road.” I had expected an easy walk but it was a hard trudge most of the way, and my boots had four inches of adobe on the bottoms at times. I remember well my feelings when after walking through a stretch of scrub oak I would round a bend and see grassland ahead ... bummer! I was reminded of the words of John Wesley Powell upon entering the Grand Canyon and seeing dangerous Precambrian hard rocks ahead: “The river enters the gneiss!” ... well ... maybe not quite that bad but pretty disappointing.

Montgomery Potrero, Salisbury Potrero in distance.

Finally I arrived at “a bucolic campsite -- Salisbury Potrero -- windmill, old wooden tank, table, fireplace, wood, & me all fenced in by barbed wire sitting in a large cow pasture.” The sky cleared completely, I built a roaring fire, took off my boots with “adobe bricks on the soles” and happily dried out my gear.

At one point there was a loud cry sounding like “a dog mixed with a rooster” but it did not continue. Then suddenly I sensed a bright light approaching from behind. My heart raced and I turned to see “a huge glowing orange light ~ the Moon ... full tonight. Outstanding!” The Cuyama Valley to the north and the sparsely-vegetated Caliente Range beyond were spectacular and ghostly in the moonlight. Two owls hooted back and forth, and Orion and his dogs marched off below the horizon. I stayed up most of the night feeling very fortunate to be on Earth.

Transect across Transverse Ranges showing vegetation types, 1976. Click to view.

Literature Cited
Hornafius, JS. 1985. NEOGENE TECTONIC ROTATION OF THE SANTA-YNEZ RANGE, WESTERN TRANSVERSE RANGES, CALIFORNIA, SUGGESTED BY PALEOMAGNETIC INVESTIGATION OF THE MONTEREY FORMATION. J Geophys Res 90:2503-2522.

Nicholson, C; Sorlien, CC; Atwater, T; Crowell, JC; Luyendyk, BP. 1994. MICROPLATE CAPTURE, ROTATION OF THE WESTERN TRANSVERSE RANGES, AND INITIATION OF THE SAN-ANDREAS TRANSFORM AS A LOW-ANGLE FAULT SYSTEM. Geology 22:491-495.

Onderdonk, NW. 2007. Vertical-axis rotation controlled by upper crustal stress based on force balance analysis: A case study of the western Transverse Ranges of California. Tectonophysics 436:1-8.

Blog Crawl Gems

2011-12-15T07:02:00.000-07:00

This Week's Treasures

First, an entertaining post by Thoughtomics: “Yeti Crabs grow bacteria on their hairy claws”. It seems Yeti crabs do their mysterious “dance” to provide nutrients to methane- and sulfur-metabolizing bacteria living on their claws. So why would the crabs do this? ... to grow food. [This makes me wonder why they are considered symbionts. Are cattle symbiotic with humans?] Included are several short videos of Yeti crabs “feeding” bacteria with their curious claw-waving, eating bacteria, and possibly fighting or mating.

Small Things Considered also posted about symbiosis and sulfur-oxidizing bacteria: "A Wormful of Bugs". Paracatenula is a flat worm that has no mouth nor gut but rather a sack filled with H₂S-metabolizing bacteria that provide its food. I won’t give away the rest of the story, it is much better told by Moselio Schaechter. Symbiotic relationships with sulfur oxidizing bacteria are widespread, involving diverse organisms including ciliates, arthropods, mollusks, a variety of worms, and even an archeon ... and of course Yeti crabs. And there are more wonderful surprises ahead I’m sure.

The Artful Amoeba has an interesting post about the hazards of air-borne Red Tide -- the Red Tide Tickle -- as well as some natural history of the blooms and the dinoflagellates involved. The post ends with an inexplicable video of a dinoflagellate waving its flagella while Billy Holiday sings Lover-man, oh where can you be.

Moving to the geological ... surely the most puzzling post of the week was by Sandatlas, with photos of the crater-like Makhtesh Ramon in Israel. The mystery is in the middle of the “crater” where there are outcrops of columnar sandstone. Columnar sandstone??? ... bizarre enough that readers quickly responded with comments and hypotheses, but still no explanation. Surely there must be one ... ??

In "Why Sugar Makes Us Sleepy (And Protein Wakes Us Up)", Jonah Lehrer of The Frontal Cortex describes research on the effects of sugar vs protein on the neuropeptide orexin, the lack of which can make us tired and slow our metabolism, among other things. And yes -- sugar ingestion results in decreased activity of orexin neurons, while protein stimulates them. Now that we better understand the mechanisms underlying the drawbacks of refined sugar, maybe it will be easier to turn down that quick-but-short-lived energy boost for something more lasting. Reach for the almonds!

Finally, way back on November 29 Botany Photo of the Day featured a black bear feasting on dandelions (Taraxacum officinale); dandelions are known to be tasty treats for bears (is there an orexin story here too?).

In the Company of Plants and Rocks

The Many Mysteries of Rock

Devils Tower -- what’s on top?

Accretionary Wedge #43 -- deadline approaching

Leaving Home

The Spiritual Side of Mud

Yuccas of the Far North

Blog Crawl Gems

Plants & Rocks: ferns and granite ... and climbers

Call for Posts: Accretionary Wedge #43, “my favorite geological illustration”

The top 10 reasons I love Wyoming geology

The photo not taken

Creatures of Stone III -- the rest of the story?

Fun in the Field: identify trees with dichotomous keys

Blog Crawl Gems

Little Bone House on the Prairie

Topographic reversal, then and now

Blog Crawl Gems

me too -- stop SOPA, PIPA

Reading Sam McGee

Scoria and cinders at Lunar Crater volcanic field

Blog Crawl Gems

Not your typical plant photos ... nor plant photographer

The Accordion Rocks

Pleistocene Relics in the Black Hills

Creatures of Stone II -- genesis

Blog Crawl Gems

My New Year's Resolutions

Plants and Rocks: columbines and granite

Blog Roundup -- yeee haw!!

Happy Birthday Frank!

Blog Crawl Gems

El Tío -- god of underground miners

Happy Geolidays to all!

Blog Crawl Gems

Recommended Reading: Geology of Northern New Mexico’s Parks, Monuments, and Public Lands

Plants and Rocks: Vegetation mosaic on Miocene marine strata ... sweet!

Blog Crawl Gems