Robert Shedlock and Scott Phillips provided helpful input during the design stage of the field effort, as did Ward Sanford and J.K. Böhlke. The work was supported financially by the USGS Coastal and Marine Geology Program and the USGS Priority Ecosystems Program. The field effort benefited significantly from the logistical support and hospitality of the Queen Anne's County Department of Parks and Recreation (Gary Rzepecki) and the Corsica River Yacht Club (Reed Rogers). The data reported here were collected during USGS Woods Hole Field Activity 07005. Brian Buczkowski, Jane Denny, and Katherine McMullen provided helpful comments on drafts of the report. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.