For those who were interested, here is an excellent guide to Falls Lake geology. Enjoy!
The Falls Lake Trail constitutes a 60-mile portion of the 1,000-mile NC Mountains to the Sea Trail (MST). Beginning at the Falls Lake Dam, it stretches westward through mostly scenic public lands in northern Wake and Durham Counties. The trail is well marked and well maintained, and it passes through two State Parks and one County Park. The 1994 CGS guide has stops in the area, as does the GSA Centennial Field Guide (SE).
Click here for the Falls Lake geology home page.
Click here for the Anne Wilkerson geology page.