Coastal Studies

Photo of Great Marshes of Barnstable, Massachusetts

The Great Marshes of Barnstable, Massachusetts
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In North America, historical records of hurricanes date back nearly 400 years, but reliable records maintained by the National Oceanic and Atmospheric Administration (NOAA) only go back to the late 19th century. Stratigraphic studies of back-barrier salt marshes along the eastern seaboard of the United States are providing records of overwash deposition associated with intense hurricanes. With an understanding of the sediment signature left behind by historic storms we are able to extend the record of these relatively rare geologic events into the prehistoric period.

In the northeast United States two major factors influence sea level: subsidence related to the isostatic response of the crust and mantle to the loading and subsequent unloading of the Laurentide Ice Sheet; and eustatic or global change in sea level related to ocean volume. The deposition of salt marsh sediments is fundamentally linked to tidal flooding frequency and their peat deposits preserve a record of past sea level. Sediment cores obtained from salt marshes from New Jersey to Massachusetts are being used to reconstruct late Holocene sea level and help quantify subsidence in the region and constrain eustatic sea level changes.

Coastal Studies     Geoarchaeology     Paleoclimates     Vegetation Dynamics