Collaborative Research: Community-Based 3D Imaging That Ties Clinoform Geometry to Facies Successions and Neogene Sea-Level Change

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The primary goal of this project is to constrain the complex forcing functions tying evolution and preservation of the margin stratigraphic record to base-level changes. These processes include eustasy, climatic and paleooceanographic variations, tectonism, compaction and rates of sediment supply. Existing borehole data will provide lithostratigraphy, geochronology and paleobathymetry. Geomorphology revealed by horizontal slices (among other 3D imaging tools) will identify diagnostic features such as river systems, shorelines, delta channels, sediment failure scars, etc., none of which can be resolved in existing 2D seismic data to the degree required to map shifting shallow-water depositional settings in the vicinity of clinoform rollovers. For the general benefit of a broad user community the PIs will coordinate and acquire a 3D seismic data encompassing the three IODP drillsites on the inner-middle shelf of the New Jersey (NJ) continental margin on R/V Marcus Langseth. Data will be made available to the engaged scientific community to use as the foundation of follow-on, PI- driven proposals that improve understanding of factors shaping the NJ margin in particular, and that imprint the sedimentary record at continental margins in general. 3D seismic imaging can now be applied to the NJ margin to put these sampled records in a spatially accurate, stratigraphically meaningful context. Such imagery will allow researchers to map sequences around drill sites with a resolution and confidence previously unattainable, and to analyze their spatial/temporal evolution. Objectives include: 1) establishing the impact of known Ice House base-level changes on the stratigraphic record; 2) providing greater understanding of the response of near-shore environments to changes in elevation of global sea level (with special relevance to the current relentless rise), and 3) determining the amplitudes/timing of global sea-level changes during the mid-Cenozoic, which should help humanity put anthropogenic base-level change in a proper long-term context. Broader Impacts The project will collaboratively engage the scientific community and generate widely accessible data for all users. Students and early-career scientists will be mentored and involved in the cruise. The PIs will produce exhibits and/or lectures hosted by the Rutgers Geology Museum. Since the source of the sedimentary record offshore New Jersey fed a similar pulse of sediments into the Gulf of Mexico, increasing knowledge of the evolution of the NJ shelf may help improve strategies for hydrocarbon exploration in the Gulf.