Pb 210 -Determined Sedimentation Rate, and Accumulation of Metals in Sediments at a Station in Chesapeake Bay

Abstract

This paper contains the first published radiometrically determined contemporary sedimentation rate, a rate characteristic of the past few decades, for any part of the Chesapeake Bay estuarine system. Cores collected from a station in the main body of the Chesapeake Bay off Tilghman Island (38°41′30″N, 76°24′00″W) were analyzed for Pb210, organic carbon, nitrogen, and selected metals. A mean sedimentation rate of between 0.09–0.12 cm/y was inferred from the Pb210 data. The distributions of C and N are typical of many areas of the Bay. The distributions of extractable Ni, Cr, Cu, and Pb increased in the upper 10–15 cm of the core. The increases in metal concentrations over the past century or so may be a result of man’s activities.