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Letchworth
State Park is located in western New
York. It is here that the North-flowing Genesee 
River
has been carving it's way through these layers of rock since the
end of the last ice advance. Rapid erosion rates make for steep
canyon walls and spectacular scenery. The Geometry of the river
valley takes on a winding course and is essentially an incised
meander, or a deeply etched sinusoidal pattern, where at the
level of the high cliff-tops the water once flowed in
semi-circular loops.The wide canyon here
was a large glacial lake when the Wisconsin (most recent)
ice sheet occupied the region twenty-two thousand years ago.
The layers of rock
you see here were all deposited in shallow seas that advanced and
retreated several times during the Paleozoic era, about up until
the Late Devonian period when continental collisions 
on the eastern side
of New York raised the land and drained the water away. This location is at a
higher elevation than Niagara Falls and buries the Lockport
Dolostone formation, though further downstream the dolomite is
exposed. Primary rock types are Sandstone, and Shale. An interesting notion about these layers is that they
dip 35-50 feet every mile you travel to the south; a product, no
doubt, of the countless mountain building episodes on the Eastern
Flank of New York since the of the Devonian Period.
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Three waterfalls are located within a two mile stretch. As the Wisconsin Ice Sheet melted away, it would create lakes within the gorge. As the ice got further and further from one waterfall, a new one would develope. In this manner the first waterfall to develope was the upper falls (left). When the lake level dropped, the Middle Falls developed, and so-on as the lower falls (right) began to erode. The waterfalls similarly share a common trait: that each of them spill over erosion-resistent sandstone layers.
Observe shear nonconformity. Shale, flaking away as it weathers in this formation contrasts with the more resilient sandstone.
Of all the places in
New York I remember being to, I have not seen a more tranquil
place to just walk around and observe. The scenery here can not
be fully appreciated in this web page, you have to go see it
yourself. The scene
makes for an ideal romantic getaway, a good hike among several
trails, great biking, clear air, several historic NY
sites--including a canal and train bridge, varieties of
plant/animal life, and just down-right awesome nature.
