Late Quaternary Paleochannel Systems on the Continental Shelf, South of the Chesapeake Bay Entrance
Keywords:
Seismic reflection, paleogeography, aminostratigraphy, channel-fill sequences, sea-level change.Abstract
Analyses of an extensive network of high-resolution seismic-reflect ion records and borehole samples outlined three distinct paleochannel systems beneath the continental shelf south of the entrance to Chesapeake Bay. Amino acid racemization analyses of mollusks from the fill sequences are used for estimation of the ages of channel cutting and filling. The principal periods of channel cutting appear to be during the sea-level minima associated with marine oxygen isotope Stages 2 and 6. An older channel-filling phase (Stage 13 or 15) is also recognized based on aminostratigraphic results. These aminostratigraphic results are consistent with the results of previous studies on the mid -Atlantic coastal plain.