Philip Bradley, Bart Cattanach, William Henika, James Hibbard, Mutlu Ozdogan, Eleanora Robbins and Paul Thayer
Edited by W.S. Henika, James Hibbard and James Beard
Full color softcover
Photos and illustrations
This one-day field trip provides an overview of a major crustal block, the Milton terrane, within the eastern Piedmont domain of southern Virginia and northern North Carolina. We will also observe rocks that immediately border on the terrane - a Mesozoic basin to the west and an Alleghanian ductile shear zone to the east (Plate 1). The specific motivation for the 2006 trip is to provide a field review of recent regional geologic mapping, petrographic studies, geochemistry and geochronology (Ragland, 1995; Hibbard and others, 1998; Coler and others, 2000; Henika, 2002). This new regional mapping and accompanying analytical work at Florida State, North Carolina State and Syracuse universities have substantially changed the face of southside Virginia Piedmont geology. Major points that have changed since the compilation of the 1993 Virginia State Geologic map in this area by W. S. Henika include:
- The elimination of a major nappe proposed to be the dominant structure of the eastern Piedmont between Danville and South Boston (Tobish and Glover, 1977) due to lack of continuity of the supposed marker units used to delineate the recumbent fold closure, linking rocks of the Carolina terrane and the Milton terrane.
- New analytical work shows that the Milton terrane and Carolina terrane are distinct and unrelated crustal blocks, separated by a significant shear zone, the Hyco shear zone, a segment of the central Piedmont shear zone.
- Analytical work shows conclusively that the Milton terrane rocks are isotopically, geochemically, and geochronologically equivalent to the Chopawamsic terrane in the central Virginia Piedmont.
It is also intended to reacquaint the geological and teaching community with the southside Virginia area as it enters the fifth century of resource exploration and development that began with the first successful English commercial expedition of the London Company now known as the Jamestown Colony. As we saw on the preliminary trips to compile the road log for the 2006 trip; you will see evidence that tobacco, the most successful product developed by the London Company is still a major force here. With our increased understanding of the potential land, mineral and water resources of the Eastern Piedmont Domain, some mineral-based products that the original settlers were seeking but failed to find may yet emerge from beneath the deep and productive soils of the region.