05/16/2017
Look at this amazing photo of the Finger Lakes from NASA!
FINGER LAKES—CENTRAL NEW YORK STATE
The Finger Lakes in Central New York State are 11 parallel lakes with long, narrow shapes. They are aligned north to south, and resemble fingers on a hand. The Iroquois believed that the lakes were evidence of marks from the Great Spirit’s hand. The lakes formed in the past two million years after carving by glaciers eroded pre-existing stream valleys in the region. The actual depth of the lakes is much deeper than they appear, as the lakes have filled partially with sediments after the carving of the glaciers. The deepest two lakes, Seneca and Cayuga, are among some of the deepest in North America and are actually deeper than sea level. For example, Seneca Lake’s surface is measured to be 135 meters above sea level, but its depth reaches 200 meters, making the lake deeper than sea level. The formation of this area has a very complex history.
Initially, the land that now features the lakes held rivers that flowed from south to north. When an Ice Age began approximately two million years ago, glaciers moved from northern latitudes to cover the area. The glaciers, which were more than two miles thick, advanced and retreated during this time period, carving out the formations of the lakes into the rocks underlying the pre-existing rivers. The region was completely covered in ice about 21,000 years ago, when the ice was at its height. The climate warmed starting at 19,000 years ago, and the last glaciers retreated completely approximately 11,000 years ago, leaving behind their mark on the land in the form of the lakes. When the ice melted, sediment clogged the river valleys, and the water filled the gorges scraped by the glaciers, creating the present-day lakes and waterfalls we see in the region today.
If you are a fossil lover like me, visit Ithaca, which is a city on the southern end of Cayuga Lake. There are many types of fossils visible in the area that were deposited during the Ordovician to Late Devonian periods when the area was buried by a warm, shallow sea; this sea was present approximately 450 to 360 million years ago. You will find abundant brachiopods, clams, trilobites, corals, cephalopods, and crinoids in the rocks in the region. Ithaca was where I found my very first trilobite!
-Jeanne K.
Photo courtesy of NASA.
References:
http://www.priweb.org/ed/finger_lakes/nystate_geo3.html
http://www.dec.ny.gov/docs/water_pdf/chapter2.pdf
http://www.priweb.org/ed/finger_lakes/nystate_geo1.html
http://nationalatlas.gov/articles/geology/features/fingerlakes.html
http://www.priweb.org/ed/finger_lakes/nystate_geo4.html
http://priweb.org/ed/finger_lakes/nystate_geo6.html