Depositional Systems on the Northern MA and NH Inner Continental Shelf: Use of High Resolution Seafloor Mapping to Understand Impacts of Glaciation, Marine Processes, and Sea-Level Fluctuations
The New Hampshire and vicinity continental shelf is extremely heterogeneous and includes extensive bedrock outcrops, sand and gravel deposits and muddy basins. Many of the depositional features are glacial in origin and have been significantly modified by marine processes as sea level fluctuated since the end of the last major glaciation. Relatively recent high resolution multibeam echosounder (MBES) bathymetric and backscatter surveys by the NOS and UNH CCOM/JHC has revealed features of the seafloor in exceptional detail that had not been previously described. Synthesis of the MBES bathymetry and backscatter, coupled with an extensive archived database consisting of subbottom seismics, bottom sediment grain size data and vibracores, is being used to develop new surficial geology maps and significantly improve our knowledge of the character and origin of the major depositional features of the New Hampshire and vicinity continental shelf (with additional support from the BOEM). Included are a number of large glacial features (e.g., drumlins) that have been modified by marine processes (waves and currents). Some of the larger features were previously mapped, but the lack of high resolution bathymetry limited their characterization and interpretation. The new high resolution bathymetry and backscatter has resolved this limitation. Some of these deposits may represent significant sand and gravel deposits on the New Hampshire continental shelf that have potential for future use for beach nourishment and other efforts to build coastal resiliency.
Larry Ward has a Ph.D. from the University of South Carolina (1978) in Marine Geology. Primary interests include estuarine, coastal, and inner shelf sedimentology and surficial processes. Dr. Ward's most recent research has focused on estuarine sedimentological processes and depositional environments, coastal geomorphology and erosion, the physical characteristics of inner shelf bottom habitats, and the stratigraphy, sea level history and Holocene evolution of nearshore marine systems. Teaching interests ranges from introductory geology and oceanography courses to graduate level coastal and estuarine sedimentology and surficial processes course. Dr. Ward is an Associate Research Professor in the Department of Earth Sciences and is a member of the Center for Coastal and Ocean Mapping and Jackson Estuarine Laboratory.