Formation
Mesa Falls Tuff, which is the rock over which Upper Mesa Falls cascades, was formed 1.3 million years ago. A cycle of rhyolitic volcanism from the Henrys Fork caldera deposited a thick layer of rock and ash across the area. This layer compressed and hardened over time.
Between 200,000 and 600,000 years ago, the river eroded a wide canyon which was subsequently partly filled with basalt lava flows. The Henrys Fork of the Snake River then carved the channel through the basalt; which is the inner canyon seen today.
Read more about this topic: Upper Mesa Falls
Famous quotes containing the word formation:
“It is because the body is a machine that education is possible. Education is the formation of habits, a superinducing of an artificial organisation upon the natural organisation of the body.”
—Thomas Henry Huxley (18251895)
“That for which Paul lived and died so gloriously; that for which Jesus gave himself to be crucified; the end that animated the thousand martyrs and heroes who have followed his steps, was to redeem us from a formal religion, and teach us to seek our well-being in the formation of the soul.”
—Ralph Waldo Emerson (18031882)
“Out of my discomforts, which were small enough, grew one thing for which I have all my life been gratefulthe formation of fixed habits of work.”
—Elizabeth Stuart Phelps (18441911)