The huge roadcut

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“This would be a beautiful place to measure the thickness of the section,” Anita said. “It’s completely exposed. It’s consistent. There are no faults. The thin green bands are where deposition was too rapid for oxidation to take place.” Evidence of geologists was everywhere. They had painted numbers and letters on the rock. They had removed countless paleomagnetic plugs. The bedding, seen close, was not monotonously even, as rock would be that formed in still water. Instead, it was full of the migrating channels, feathery crossbedding, natural levees, and overbank deposits of its thoroughly commemorated river. There were little maroon mud flakes. They were plucked off flats in a storm. We went back a few miles and slowly reviewed the rock. When again we approached the huge roadcut, Anita said, “In Illinois, this would be a state park.”
The bedding planes of the Holy Toledo cut, as I would ever after refer to those enormous walls of red stone, were dipping to co-working space rotterdam the east. Over the past few miles, the rock of the country had been folded ninety degrees. To the immediate west, therefore, we would be goiilg down in time and predictably would descend in space to a Cambra-Ordovician carbonate valley, which is what happened, as the road fell away bending left and down into Nittany Valley, where ribs of dolomite protruded here and there among rich-looking pastures turning green, gentle streamcourses, white farms. “Penn State sits on Nittany dolomite,” Anita said. “Ifs twenty miles down this valley.” Some remnant Cambrian sandstone formed a blister in the valley. The interstate drifted around it in a westerly way and toward the foot of still another endless mountain-Bald Eagle, the last ridge of the deformed Appalachians. After theĀ co-working space amsterdam Cambrian sandstone, the Ordovician dolomite, there was Silurian quartzite in the gap that broke through the mountain. Its strata dipped steeply west.

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