Friday last Pam and I joined a “James Potorti Memorial Gorge Walk” through Buttermilk Falls State Park where we learned interesting facts connected to one of my most successful photographs, “Summer Dream: Buttermilk Falls.” This is the second post of this series.
Many Right Angles, Why?
On a July morning 2018 I walked Buttermilk Creek from the scene of my “Summer Dream: Buttermilk Falls”, up the steps on the right of that photograph to where the water flows across a flat expanse of stone. This is a photograph of that expanse taken using a tripod mounted Canon EOS 1DS Mark III body with the Canon lens EF 24mm f/1.4L II USM w/a neutral density filter (0.6 as I recall).
Click photograph for a larger view.
For a scene from nature there are many straight lines and, even, right angles in addition to the layering of the sedimentary rock from its origin as eroded material from the ancient Arcadia mountains collected on the floor of a warm shallow sea. We learned from Friday’s walking tour this sea was close to the equator at that time, riding on a tectonic plate that’s since drifted north. This North American Plate jostling with the others.
Beneath these rocks were older formations in which decomposed organic matter had transformed to methane gas. When the African plate and this pressed together, the stressed rocks weakened at right angles to the force, each stress point joining others in straight lines. The methane gas pressure from below forced the weak points to open a straight line fractures.
As the plates continued to move, orientation to the African plate transformed by ninety degrees and the two pressed together again. Methane gas pressure was present, causing straight line fractures at right angles to the others. Everywhere these rocks are exposed across the Finger Lakes region we see these right angle fractures.
James Potorti was a native of Ithaca who perished at 52 years of age in New York City on September 11, 2001 were he worked on the 96th floor of 1 World Trade Center.