THE MINERALOGY, PETROLOGY, AND PROVENANCE OF BALLAST STONES FROM THE CAPE FEAR, NORTH CAROLINA: 1726 – 1825
This study examines ballast stones collected from Campbell Island, the historic transshipping point on the Cape Fear River, in southeastern North Carolina. The goal was to evaluate the geologic and geographic provenance of the ballast as well as to correlate these results to shipping trends and ports of origin for this area from 1726 to 1825. The ballast recovered was separated into four groups: a mafic igneous rock suite (basalt or diabase), a chalk-flint-chert group, a suite of quartz-rich plutonic igneous rocks (granite) and a mixed group of sedimentary and metasedimentary rocks. The provenance of the ballast was determined by the mineralogical and petrographic characteristics of the mafic and quartz-rich plutonic rocks, which was further correlated with the few existing shipping records for this region. Petrologic methods and microfossil identification suggest that chert and flint ballast stones in the region may also have a Caribbean origin, in addition to English or French origins previously reported. This observation could have implications for the importation, use, and later embargo of flint (or chert) by the British prior to the American Revolution of 1775.