Abstract
Four “reference sites” were established in 2023 in the Western Gulf of Maine (WGOM) for the specific purpose of testing and evaluating acoustic systems (i.e., sub-bottom seismic profilers) by the University of New Hampshire (UNH) Center for Coastal and Ocean Mapping and Joint Hydrographic Center (CCOM/JHC). Determination of the reference sites was guided by a detailed understanding of the surficial geology and shallow subsurface stratigraphy based on an extensive database developed over several decades by UNH. The reference sites include a high-energy channel deposit (Portsmouth Harbor Entrance: PHE), a large sand shoal (Northern Sand Body: NSB), a paleodelta (Merrimack Paleodelta: MPD), and a muddy basin (Scantum Basin: SB). Use of the reference sites facilitates qualitative, but geologically informed, evaluations to be made among differing acoustic instruments. Exceptionally strong reflectors were identified in all the reference sites including layered shoal deposits, subsurface bedrock, glaciomarine sediment, deltaic deposits, erosional unconformities (ravinement surfaces), gas, and pockmarks. The four reference sites are described in separate sections, each providing high-resolution bathymetry and surficial geology maps with sediment classifications developed by the Center, bottom sediment grain size data, and examples of sub-bottom seismic stratigraphy.
Publication Date
2025
Digital Object Identifier (DOI)
Document Type
Report
Recommended Citation
Ward, Larry G.; Morrison, Rachel C.; and Bogonko, Michael, "Western Gulf of Maine Acoustic Assessment Reference Sites" (2025). Center for Coastal and Ocean Mapping. 1752.
https://scholars.unh.edu/ccom/1752