CAROLINA TERRANE METAVOLCANICS: FEW'S FORD - ENO RIVER STATE PARK, DURHAM, NC

The falls at Few's Ford access area in Eno River State Park, near Durham, NC, expose outcrops of Late Proterozoic-aged (ca. 615 – 630 Ma) volcanic rocks assigned to the Hyco Formation of the Virgilina sequence of the Carolina terrane. Outcrops exposed on the west side of the falls have been interpreted as lahars by past workers. The rocks are green to dark green, matrix supported, polymictic, poorly sorted, immature meta-conglomerates. Clasts are angular to subrounded and range in size from a few millimeters up to 1 meter. Clasts types include flow-banded lavas, tuffs, porphyritic intrusive rocks and fine- to medium-grained intrusive rocks. Some clasts display appreciable rounding suggesting possible reworking in a stream. At times of low water, a metamorphosed mafic dike ranging from 3 to 4 feet wide crosscuts the meta-conglomerate and can be traced for several feet. Outcrops on the east side of the falls consist of lithic meta-tuffs with clasts of black-colored plagioclase porphyritic dacite and dacitic lavas with hyaloclastic textures. Deposition is interpreted to have been relatively proximal to a volcanic vent of dacitic composition within a paleovalley that was infilled with lahar flows, lavas, and lithic tuff. Original depositional layering is steeping dipping due to folding attributed to the Virgilina deformation.

Detailed topographic data indicates the presence of abundant lineaments that suggest widespread brittle faulting overprint (Mesozoic age?) of Carolina terrane rocks. Two of these lineaments intersect immediately upstream of the Fews Ford area and are responsible for the high-angle bend in the Eno River. Erosion of the lineaments and other fault zones may have formed landscape conditions suitable for a ford and mill site by early settlers.