Journal
of Cave and Karst Studies
- ISSN 1090-6924
Volume 65 Number 2: 126-129 - August 2003
A publication of the National Speleological Society
Abstract
The Ohio Geological Survey has recently
published a map showing the locations of known and probable karst in Ohio. The
map shows some areas of karst developed on the extremely shaly Ordovician limestone
of Hamilton County, in the southwestern corner of the state. Detailed mapping
of these sinkholes in Mt. Airy Forest, a municipal park near Cincinnati, shows
that they occur only where the lower 10 m of the Corryville Member of the Grant
Lake Formation is the surface bedrock. Of the many sinkholes in the study area,
only one is evident on the 1:24,000 USGS topographic map. The expression of
sinkholes on contour maps is dependent on the size of the sinkhole, as well
as the scale of the map, the contour interval at which the topography is sampled,
and the slope of the ground surface around the sinkhole. It is possible to determine
the minimum size of sinkhole which will consistently be expressed on a given
part of a contour map. Conversely, it is also possible to determine the scale
and contour interval which will be necessary to consistently indicate the presence
of sinkholes of a given minimum size.
This page last updated:
5 November, 2004 5:55
Web Author: Jim Pisarowicz