2012_06_12 Upheaval Dome
Shots of the Upheaval Dome, an impact crater, probably of Jurassic age, in Canyonlands National Park west of Moab, Utah. It's about 5 km (2 mi) across.

Rising in the center of the dome is the oldest rock: Permian Organ Rock Shale. Obove this are Permian White Rim Sandstone. Both of those are part of the Cutler Formation. Above those, in shades of red, are the Triassic Moenkopi Formation, the late Triassic Chinle Formation, Wingate Sandstone, Kayenta Formation, and Navajo Sandstone. That's the whitish (though often red) rock at the surface surrounding the crater. Navajo crosses over into Jurassic time, which starts 200 million years ago. The bolide (that's geologist for meteorite) hit sometime after that.

When I visited it on the ground in 1987, there were many signs explaining it as an eroded salt dome. I thought at the time it was an impact crater, but the signs refuted that. No longer. This Utah Geological Survey page reports recent findings by German scientists supporting the impact theory. So, I believe, do the apparently compressive concentric rings in the rock surrounding the rim of the crater.
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