A Marine Archaeological Reconnaissance Using Side-Scan Sonar, Jamestown Island, Virginia, U.S.A.

Abstract

A detailed side-scan sonar survey of the shallow region immediately offshore of Jamestown Island, Virginia, specifically conducted for archaeological purposes, disclosed numerous anthropogenic or unexplained features including an outline of one feature having dimensions of many tens of meters. These items are of particular interest as Jamestown Island is the site of the earliest successful English settlement on North America. The major feature in the imagery was in an area thought a likely location for the fort constructed in 1607, the region having been drowned by the ensuing rise in sea level. Subsequent investigations of the features depicted on the sonograms, first by waders and swimmers, later during a plane-table survey, retrieved seventeenth-century artifacts but were inconclusive in better identifying the major feature as other than a series of very subtle ridges with no immediately discernible underlying structure. Although providing no specific evidence, analysis of historical maps and charts suggests that this structure might be related to a recent pier that had been constructed slightly downstream from and in deeper water than the site of interest. The origin and history of the large, anthropogenic feature remain unknown and require further investigation.