20 March 2013
Upper Martinsburg “Cub Sandstone” in GigaPan
Posted by Callan Bentley
Today, two GigaPans shot of the uppermost Martinsburg Formation, informally known as the “Cub Sandstone” since it crops out along Cub Run in the southern part of the Massanutten range. 10 or 15 meters upsection (west) of these two outcrops is the base of the Silurian-aged Massanutten Sandstone, the ridge-forming unit.
Lower in the section:
link
Higher in the section:
link
If you explore these GigaPans, you’ll find a trend towards less mud and more sand higher in the section (to the west / left), which is interpreted as evidence of basinal shallowing. You’ll also see some killer bedding/cleavage intersections, and great examples of spheroidal weathering in the sandstone layers. Enjoy!
Callan Bentley is Associate Professor of Geology at Piedmont Virginia Community College in Charlottesville, Virginia. He is a Fellow of the Geological Society of America. For his work on this blog, the National Association of Geoscience Teachers recognized him with the James Shea Award. He has also won the Outstanding Faculty Award from the State Council on Higher Education in Virginia, and the Biggs Award for Excellence in Geoscience Teaching from the Geoscience Education Division of the Geological Society of America. In previous years, Callan served as a contributing editor at EARTH magazine, President of the Geological Society of Washington and President the Geo2YC division of NAGT.