Tidal
surges from large storms and hurricanes deposit sand.
Ocean to the left and tidal lagoon to the right form a barrier-beach salt marsh.
Paleotempestology
Paleotempestology New England Hurricanes Sea Level Rise
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Tidal
surges from large storms and hurricanes deposit sand. |
Jeff Donnelly, a postdoctorate currently working out of Woods Hole, Massachusetts, and Rick Lederer, a former Masters student, have completed initial work on reconstructing the history of intense hurricanes striking the east coast from New Jersey to Maine.
Cores of saltmarsh sediments contain layers of sandy overwash deposits
between layers of peat. (See below.) The animation on the right shows the working model
for the deposition of these layers as the salt marsh grows upward and landward in the face
of continuing sea-level rise. Transects of vibracores allow the mapping of the overwash
fans. We have matched the upper-most overwash fans to aerial photos of the fans after
known hurricanes and then matched the lower sand layers to other historically known
storms. Prehistoric sand layers are radiocarbon dated and provide records of possible
prehistoric storms. The salt marsh cores provide records of 600 to 1000 years and add key
information for calculating the long-term return rates on intense hurricanes that make
landfall. This research is sponsored by the Risk Protection Institute of the Bermuda
Biological Laboratory for Research.
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Overwash
Deposits |
Vibracore
Sediment Extraction |
Related Links
Coastal Studies Geoarchaeology Paleoclimates Vegetation Dynamics