Upheaval Dome

Upheaval Dome doesn't fit — in a park where the geology is orderly, where the sedimentary layers lie flat and legible for miles, the dome is three miles of rock pushed into a crater and a rim, the strata folded and faulted in a circle that has no business being there. Canyonlands calls it the belly button; the question is whether it's an innie or an outie.

The two theories ran for decades. The salt-dome camp held that the Paradox Formation — the deep salt layer under the Colorado Plateau — had pushed up through the overlying rock like a bubble, then been pinched off and eroded back to the stem. The impact camp argued the dome was a meteor crater: a body roughly a third of a mile across hitting sixty million years ago, the center rebounding into the uplifted ring the structure shows now. The evidence was thin on both sides — no salt remnants, no shocked quartz — until 2007, when Buchner and Kenkmann found the shocked quartz grains in the Kayenta sandstone, the deformation features that only form under impact pressures. The crater camp won.

The dome is what's left of the hit — the mile of rock that covered the crater has eroded off, leaving the central uplift and the ring syncline exposed at the surface. The trail goes up to the rim overlooks; from above, the bullseye is unmistakable — the oldest rocks in the center, the layers dipping away in rings, the whole structure a fossil of the impact in stone.

Upheaval Dome is the archive's impact file — the meteor crater that passed as a salt dome for sixty years until the shocked quartz proved the hit, the circle in the Canyonlands where the rock remembers being struck.