Near Yellow Springs in Greene County, Ohio — The American Midwest (Great Lakes)
—Part of the Clifton Gorge/ Glen Helen Complex —
Ohio’s bedrock is all sedimentary. It was laid down upon the floors of the ancient oceans which periodically inundated the state. Conditions changed over the eons in these waters, dictating the different types of sediments that we now see as bedrock. Compaction over subsequent millions of years, compressed the materials into rock.
Ohio’s general bedrock types include sandstone, shale and limestone. The first two are formed from sediments washing into the sea from nearby land masses. Sandstones and comglomerates represent periods when coarse-grained and larger materials were introduced from relatively swift flowing rivers. Shales are former from finer sediments such as muds. Limestone usually represents an area where the sea was deeper and clearer. Lime precipitates out of the water, accumulating as a mud with many shell fragments on the sea floor.
Ohio’s sedimentary rocks form layers with the oldest strata at the bottom. These layers dip slightly to the southeast and northwest in the corners of the state while they are fairly level from Cincinnati north to Toledo. This dome or arch is a feature of the bedrock itself while surface erosion has cut evenly across the state. Therefore, different layers are exposed across Ohio with the oldest at the center of the arch and younger layers in the southeast and northwest.
Clifton Gorge of the Little Miami River here at John Bryan stands in sharp contrast to the relatively flat landscape of most of western Ohio. Rock and soil debris, spread over three fourths of the state during the Pleistocene Ice Age, buried most old bedrock valleys. Here, however, the story is obviously different.
The continental ice sheet blocked the preglacial routes of many streams including that of the Little Miami. Glacial meltwaters then rapidly cut this new spectacular 70 foot deep gorge for the river through middle Silurian dolomite.
During the period 420 million
A spring walk through the gorge is a very pleasant experience. A wild diversity of wildflowers flourish in the rich soils while warblers sing from the budding trees. Nowhere is the show of bluebells and hepatica quite so pretty as beneath these towering cliffs and on the banks of the pristine, officially designated Wild and Scenic River.
Erected by Ohio Department of Natural Resources.
Location. 39° 47.653′ N, 83° 50.468′ W. Marker is near Yellow Springs, Ohio, in Greene County. Marker is on Orton Memorial Parking Lot, on the right when traveling north. Click for map. enter John Bryan State Park through the main gate at St Rt 370. Continue on park service roads to the east as far as possible, approx. 1 1/2 miles, to the Orton Memorial Parking lot. This marker is off the northeast corner of the parking lot, at a trail head. Marker is at or near this postal address: 3790 State Route 370, Yellow Springs OH 45387, United States of America.
Other nearby markers. At least 8 other markers are within 2 miles of this Orton Memorial (approx. 0.2 miles away); Camp Birch (approx. 0.4 miles away); Clifton Gorge (approx. 0.6 miles away); Clifton Gorge Marker (approx. 0.7 miles away); Historical Clifton (approx. 0.8 miles away); Erastus Mitchell Birch (approx. 1.7 miles away); Horace Mann (approx. 1.7 miles away); Historic Grinnell Mill (approx. 1.9 miles away). Click for a list of all markers in Yellow Springs.
More about this marker. Text is VERY extensive, other than the Lion’s Club Marker in West Liberty, this is the wordiest marker I have found yet.
Categories. • Environment •
Credits. This page originally submitted on , by Rev. Ronald Irick of West Liberty, Ohio. This page has been viewed 231 times since then and 4 times this year. Photos: 1, 2, 3, 4, 5, 6, 7. submitted on , by Rev. Ronald Irick of West Liberty, Ohio. • Al Wolf was the editor who published this page. This page was last revised on June 16, 2016.