Geology Hike – Tuesday, December 1, 2009

In spite of a very chilly morning, 26 hikers enjoyed an informative walk and talk by retired geology professor David Hutchison. David started us at the lower and older Middle Devonian exposed bedrock at Nicks Diner. The muds that formed these thinly bedded shale layers were deposited in a quiet sea during a time when the entire area was at a lower elevation and under water. We then went up the hill to the rock layers behind the Science building. Dave explained that the thicker, stronger layers of sandstone were most likely deposited in a ancient stream bed that filled with sand interspersed with layers of a fine shale. Continuing uphill we walked to the top of Oyaron Hill by the practice field and observatory. There we saw Devonian “red beds”- layers of sandstone and conglomerate that had been deposited at or near the surface when the area had uplifted and /or sea levels had fallen. Oxygen in the air combined with the small amount of iron present in the sediments (oxidation or rusting) to give a reddish hue to the rock layers. In this layer David pointed out casts of roots from plants that had grown in these sediments. A short walk through the woods brought us to Table Rocks where we enjoyed a windy view of the valley and pondered on the vision of ice and then a glacial lake filling the valley from hillside to hillside. Susquehanna Chapter extends it thanks to Dr. Hutchison for taking us back in geological time. Photographs by Doug Fielder (1, 9) and Linda Seifried (2,3,4,5,6,7,8). Photographs include: 1) David Hutchison, 2 & 3) Observation of Mud Shale, 4 & 5) Observation of Sandstone, (6 & 7) Observation of Red Bed, 8) Root Casts, and 9) Oneonta from Table Rocks.