Distribution of Holocene Sediment in Chesapeake Bay

The distribution of sedimentary environments presents the limited domain of deposits from "River Input", the flood tide wedge of "Atlantic Sediment", and the extensive region of indigenous, recycled "Coastal Erosion Sediment" in the Chesapeake Bay littoral environment. Studies by Miller (1982, 1983, 1987) along selected reaches of the tidewater Potomac River showed that bluff retreat in the littoral environment could be measured and modeled at as much as 0.5 to 1.0 m/yr. During the September 18, 2003 Hurricane Isabel storm surge of nearly 3 m, as much as 8 to 10 m of coastal erosion was measured near some of Miller's sites. Storm-driven coastal erosion is the most extensive source of Holocene sediment in the modern Bay. Although massive amounts were eroded from the terraces and uplands during lowered sea level and cold climates, presently most sediment eroded and transported from terrace and upland source areas has been stored on slopes and alluvial bottoms of the Coastal Plain landscapes that surround the Chesapeake. [Summary provided by the USGS.]