Radiocarbon dating of paleoliquefaction features near Bluffton in Beaufort County, South Carolina, indicates a likelihood of four prehistoric seismic events that occurred at 500 ±180, 1180 ±220, 2355 ±365, and 3355 ±485 yr B.P. Among these, the 500 ±180 and 2355 ±365 yr B.P. events appear to have originated near Bluffton, outside of the currently active Charleston seismic source zone. Association of these two events with a local source near Bluffton conflicts with the idea of periodic activation of a single seismic source near Charleston. The felt shocks of 1826, 1903, and 1912, reported from ∼20 km south of the paleoliquefaction sites, and a small earthquake on January 1989 located near Bluffton indicate that this area has been moderately active in historic times. Releveling data have identified an ∼30-km-long zone of uplift in the area. Stratigraphic data indicate the presence of an east-trending buried fault in the vicinity. These observations imply the presence of an additional seismic source zone in the South Carolina coastal plain, near Bluffton.

First Page Preview

First page PDF preview
You do not currently have access to this article.