The effects of continent-continent collisions can be felt far into the continents that are involved. Today’s collision between India and Eurasia, which has been going on for 30 or 40 million years, has helped to produce extension 2500 miles, 3700 kilometers away from the collision, at Lake Baikal in Siberia.
The Appalachian-Ouachita Orogeny had impacts as far away as Iowa quite early in the collision. Early Mississippian marine carbonate rocks were tilted and folded and uplifted and eroded before Pennsylvanian coal-bearing strata were deposited. There’s a pretty good unconformity between those sets of rocks.
—Richard I. Gibson
Reference: Coal Deposits of Iowa, by C.R. Keyes, Iowa Geological Survey, 1894.
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