Name/Title
S08.01.078Description
Downstream from Old Man's Cave, Old Man's Creek encounters the resistant lowermost zone of the Black Hand Sandstone and cascades into a broad plunge pool as a scenic waterfall known as the Lower Falls. On the face of the Lower Falls visible from above is the erosional feature known as Sphinx Head. The profile displays small scale effects of erosion and weathering on the Black Hand Sandstone. The slight parallel recesses from the chin to the mouth and in the brow are caused by weathering along bedding planes. Pitting at the forehead and honeycomb weathering along the cheek are the results of removal of individual sand grains by water as it disolves the cementing material. The jutting chin was formed by the stream undercutting the rock, permitting blocks of rock to break along bedding planes and fall into the stream. Bedrock is from the Mississippian Geologic Period. This photograph was awarded first place in the 1983 Ohio Geology Slide Contest.
Information taken from The Geology of Hocking State Park by John F. Hall (Ohio Geological Survey, Information Circular No. 8, 1953) and Geology of the South Bloomingville Quadrangle, Hocking and Vinton Counties, By Richard M. DeLong (Ohio Geological Survey, Report of Investigations, No. 63, 1968) and Geology of the Hocking Hills State Park Region by Michael C. Hansen (Ohio Division of Geological Survey, Guidebook No. 4, 1975).
This slide image included in the USGS National Digital Catalog for NGGDPP Grant G15AP00115 in FY2015.Context
Rock boulders with stream moving downwards. Old Man's Creek in Hocking Hills State Park.