|In situ. Proud geo-geek for scale.|
|Where on Google Earth? (click on photo for better view).|
Answer: They share a contact ... in spite of the huge difference in their ages!
|Stratigraphic column for Colorado National Monument; courtesy NPS. Red arrow shows contact.|
Softer red Chinle Formation erodes to form slopes above harder Black Canyon schist.
This is the Great Unconformity at Colorado National Monument near Grand Junction. The late Triassic Chinle Formation lies atop the Precambrian Black Canyon schist -- a gap of 1.7 billion years in the rock record! We love such things!!
Everyone wanted to share in the spiritual experience.