This project will develop the first regional sedimentary framework for the Delaware River Estuary
in order to elucidate the influences of estuarine hydrography, near-bed hydrodynamics, and
anthropogenic impacts on modern sedimentary processes and bottom environments.  The overarching
objectives of this research are twofold: (1) to identify spatial gradients in bottom-sediment types and
morphologies and (2) to establish causal relationships between these properties and local
hydrodynamic forcing mechanisms.  A combination of state-of-the-art marine sedimentological and
geophysical techniques will be employed to investigate the sedimentary geology of the estuarine
turbidity maximum zone, located between the Delaware Memorial Bridge and Ship John Shoal.
Comprehensive side-scan sonar and seismic (chirp) surveys will be conducted to image and map
flow-related features of the estuarine floor and shallow sub-bottom.  Subsequently, sediment cores
will be collected throughout the study area for sedimentological studies, which will provide a physical
basis for an analysis of the sonar/seismic data.  These ground-truthing studies will facilitate
extrapolation of findings between coring sites based on the sonar/seismic data alone.  Together, these
data will be interpreted in the context of past and ongoing observations of estuarine current flow and
sediment transport, as well as historical bathymetric surveys, to classify bottom environments in terms
of sedimentary-hydrodynamic processes and products.  In addition, the sonar and new bathymetric
data will reveal anthropogenic disturbances to the estuarine floor and provide a means to assess their
implications.  It is anticipated that this study will enhance our fundamental understanding of relations
between sediment transport and the morphology and stratigraphy of the upper Delaware Estuary
and thereby improve the scientific basis for management of related problems such as contaminated
sediments, shoaling of the navigation channel, and the impacts of subaqueous disposal of
dredge-spoils.
 

Launch of Slow Corer

Slow Core

Bottom Grab Sample

Sedimentology of the Delaware Estuary Home Page

Abstract of Presentation at 2002 Northeast GSA Meeting, Springfield, MA

Abstract of Presentation at 2003 U.S. Hydro Conference, Biloxi, MS

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