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Join the Honeoye Valley Association's Annual Meeting on July 13, 2019, with Dr. Bruce Gilman from the Finger Lakes Community College. Learn about the Pleistocene "Great Ice Age" and the unique landscapes it created, with insights on glacial formations and the formation story of the Finger Lakes region. Discover the impact of selective linear erosion, proglacial lakes, and valley moraines on the Finger Lakes' characteristic U-shaped glacial troughs. Delve into the region's prehistoric inhabitants, including giant beavers, wooly mammoths, and saber-tooth cats. Thank you for joining this educational session!
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Glacial Geology of the Finger Lakes (with a focus on Honeoye Lake)
Honeoye Valley Association Annual Meeting Saturday, July 13, 2019 Dr. Bruce GilmanDepartment of Environmental Conservation and HorticultureFinger Lakes Community College3325 Marvin Sands DriveCanandaigua, New York 14424Bruce.Gilman@retiree.flcc.edu
Acknowledgements • Dr. Richard Young, SUNY Geneseo • Dr. David Barclay, SUNY Cortland • Dr. Henry Mullins, Syracuse University and • Herman Leroy Fairchild, University of Rochester
THE PLEISTOCENE,“GREAT ICE AGE” A Very Different North America 20,000 years ago
Ocean levels fell by over100 meters (300 feet)! A cycle that repeated itself several times during the Great Ice Age
Warmer & less ice Interglaciations Glaciations Colder & more ice Pleistocene Ice Ages starting ~2.5 million years ago ending 10,000 years ago Raymo, 1992
How extensive? • 10% of our modern landscape is covered by glacial ice. • During the Great Ice Age, 32% of the global land surface was covered!
Today Quaternary North America - Ron Blakey
Greenland IS 20,000 years ago Laurentide Ice Sheet Quaternary North America - Ron Blakey
Honeoye Regionat the peak of glaciation Antarctica - Kevin McMahon
Ice Sheet Marginadvancing across upstate NY Lake Uplands
Selective Linear Erosion • Glacial ice has a preference to move in pre-existing stream valleys aligned with basal flow direction – it’s the area of least resistance! • Any meanders in the original stream flow pattern are straightened out – glacial ice does not bend!
Ontario basin R S G C I H B A Finger Lakes Formation Story(pre-glaciation drainage patterns)
Ontario basin R S G C Proglacial lakes I Proglacial lakes H B A Finger Lakes Formation Story(ice sheet advance)
Ontario basin R S G C I H B A Finger Lakes Formation Story (ice sheet maximum)
Ontario basin R S G C I H B A Finger Lakes Formation(Valley Heads Moraine deposition)
Ontario basin R S G C I H B A Finger Lakes Formation(Drainage Divide Today)
Water Erosion V-shaped rocky stream bed Ice Erosion U-shaped glacial sediment fill
The Finger Lakes Region contains 28 broad U-shaped glacial troughs, 11 of these valleys are doubly dammed (north and south ends) by moraine deposits and contain water!
Alaska – Ice Park Campground Glacial Lake Honeoye Landscape, 12,000 years ago
Migrating herds of large herbivores I couldn’t resist – great movie!
With the Predators came the first Americans, Stone Age hunters
THANK YOU for attending today’s annual meeting