Telltale Sandstone

By William T. Hathaway


We were on a field trip to the cliffs on the Banister River near Markham in Pittsylvania County, Virginia. Students searched for a textbook sample of sandstone. Of the many hand-sized rocks found, a particular rock grabbed our attention. Why did this specimen seem different from the other fine-grained sandstones collected? Several of the students theorized that one side of the specimen was exposed to natural elements of weathering, fostering the delineation of geologically ancient events. One could clearly see trace fossil lines of cross-bedding. Were these fine lines of cross-bedding the result of small windblown sandstone dunes or water flow events?

The student who found this unusual specimen stood high among his peers. This rock contributed to the overall success of discovery in an enjoyable local field trip.