Choosing a seismic source for a shallow reflection survey can be the most pivotal decision for the engineering geophysicist. The intent of this paper is to present data that will assist in selection of a shallow seismic source best meeting the goals within the constraints of specific projects, particularly in areas where the water table is near the surface. The data were collected (and displayed as seismograms and amplitude spectra) for 15 different shallow seismic sources in October, 1985, at a single site in New Jersey; they show the different characteristics of each source. Considering the almost three orders of magnitude difference in total source energy between the largest and smallest source, we chose a display format that presented the data as objectively as possible, while still allowing direct source‐to‐source comparisons. Two strong reflections at about 100 and 130 ms probably mark the top and bottom of a clay unit 80 m below the surface at this site. Our previous work and that of our colleagues suggests that, given a specific set of site characteristics, any source could dominate the comparison categories addressed here.

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We have repurposed high-resolution marine seismic profiles and vibracores collected from 1 to 10 km offshore Brigantine, New Jersey, to locate, characterize, and interpret the Holocene transgression across the land/sea interface. This storm-dominated, low-slope shelf had experienced large eustatic shifts during the late Pleistocene and Holocene, causing significant lowstand erosion during marine isotope stages (MIS) 6, 4, and 2, leaving fragmented sediment packages from the intervening highstands, which were further eroded by Holocene transgressive wave energy and submarine currents. Using sediment ages tied to seismic reflectors, we mapped the offshore surficial geology of the late Pleistocene and Holocene for the first time in this region. We tied the offshore geology to contiguous onshore surficial geology using borehole geophysical gamma logs, cores, and dated material from barrier-island, estuary, and salt-marsh environments, leading to several new findings, specifically (1) that a back-barrier marsh existed approximately 16 m below the present-day sea level and 7 km seaward of Little Egg Inlet 7960 AE 210 (calibrated) before the present (AD 1950), (2) that shoal features were massed in a sediment prism south and west of Little Egg Inlet, and (3) as the Holocene sea level rose, Little Egg Inlet varied little from its current location, fixed in place by the incised valley of the paleo Mullica River, a major upland drainage system since at least MIS 6.

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The future of coastal resilience or restoration plans which implement natural or nature-based features largely depends upon the identification of proximate and compatible offshore sand and gravel material. BOEM’s Marine Minerals Program (MMP) is multi-faceted, focusing on coordinated leasing of sediment for extraction, inventorying sediment resources through geological and geophysical surveys of the Outer Continental Shelf (OCS), and environmental studies and reviews to inform decisions. However, on a national scale, little is known about the character, quantity, and location of sand resources on the OCS and the habitat it provides for biological communities. BOEM places a high priority on creating a comprehensive national sand resource inventory to meet BOEM’s mandate as stewards of all federal mineral resources on the OCS. This stewardship responsibility will be realized by proactively planning for the increasing demands for OCS resources and emergency needs as they arise.