Differential weathering in the Manhattan Schist
S.E. Central Park:
weathering
Piedmont rocks exposed in a creek
One of the cool things about being the local geoblogger is that people get in touch with you about local geology. Sometimes this even leads to meeting up for field trips. Here’s two quick photos from a recent (January 2010) field trip to a creek near Springfield, Virginia. My host was Barbara X, a local … Read more
Shear bands in amphibolite
Check out these cool structures in one of the amphibolite bodies exposed along the Billy Goat Trail (C&O Canal NHP, near Potomac, Maryland): Those are shear bands — basically small shear zones that are discretely localized within a larger body of less-deformed rock. Note the grain-size reduction visible in the shear bands, their dextral sense … Read more
A small shear zone
Back at NOVA Geoblog, I spent a portion of September and October 2009 reviewing the geological wonders I witnessed as part of a GSA field forum in the Owens Valley of California. However, I got distracted by other things, and never finished the series. I’d like to pick up on that today, looking at a … Read more