Sunday, January 15, 2012

Scoria and cinders at Lunar Crater volcanic field

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.