Sedimentology of a Morphologically Complex Seafloor Environment, New Jersey Continental Shelf
Abstract
LONG-TERM GOAL. The overarching goal of this research is to advance our understanding of "geologic clutter", acoustic anomalies created by natural sub-seafloor features such as infilled paleochannels, using the continental shelf off New Jersey as a natural laboratory. OBJECTIVES. As part of the ONR Geoclutter initiative, the objectives of this project are as follows: (1) to identify modern Holocene sedimentary processes responsible for the morphology and sedimentological heterogeneity of the seafloor; and (2) to determine the physical basis for seismic discontinuities and associated stratigraphic surfaces in the shallow subbottom. To meet these objectives, coordinated geophysical and geological studies have been performed to characterize the sedimentology and stratigraphy at priority Geoclutter sites on the continental shelf. APPROACH. The research approach involved geological groundtruthing of two sonar datasets previously generated for the Geoclutter study area: (1) multibeam acoustic backscatter derived from Simrad EM1000 (95 kHz) multibeam bathymetry (Goff et al., 1999); and (2) chirp seismic stratigraphy using a system developed by Florida Atlantic University (1.5 15 kHz pulse bandwidth). To correlate acoustic backscatter and seabed sediment type, the sedimentology of short cores collected aboard the RV Cape Henlopen in 2001 (cruise CH01 17) was characterized by the PI (UDel Task 1/2). To determine the physical basis for subbottom seismic reflectors at selected Geoclutter sites, AHC-800 drillcores were recovered aboard the RV Knorr in 2002 (cruise KN-168) by a team of scientists from DOSECC, University of Texas Institute of Geophysics (UTIG), Skidaway Institute of Oceanography (SKIO), University of Delaware (UDel), and Georgia State University (GSU). Specifically, the PI conducted aboard-ship measurements of sediment physical properties on the drillcores using a GeoTek multisensor core logger (UDel Task 2/2).
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 2003
- Accession Number
- ADA628100
Entities
People
- Christopher K. Sommerfield
Organizations
- University of Delaware