The forming and break-up of ice plains, ledges and islands as temperatures rise and fall, occurring over hours and days, form a contrast and a parallel to the deep history of the river's bedrock, formed and broken up over millions of years.
Multiple episodes of continental shifts, mountain building and volcanic activity added to, then ripped up the constellation of rock types which lie beneath our Vermont feet. The "drift" of continental plates, like the movement of ice islands seen on the Qttauquechee, caused a demolition derby, the latter swiftly, the former in motion so slow even the imagination can't picture it, though science can describe it with some precision.
As the volume Where the Great River Rises explains, "Through the action of plate tectonics, continents crash together and break apart forming mountains and opening oceans. The force of collisions create great faults many miles inland, areas of weakness in the rocks that are the paths of least resistance for water."
The course of rivers keeps alive the stories of continents.
No comments:
Post a Comment