Nearshore, slope and deepwater sediment transport mechanisms: Combining novel and legacy open source seismic datasets in marine Bonaire
We utilize a high-resolution marine seismic dataset off leeward Bonaire in the South Caribbean to show sedimentary pathways between terrigenous and shallow water sediment to sedimentary deposits exhibited in open source deepwater seismic profiles. Although prior studies have been conducted in the deep water and on the land, nearshore imaging is complicated by the shallow water depths, thin and sparse sedimentary cover, and a hard carbonate seafloor. Through the study of the nearshore slope environment, we hope to define sediment pathways and transport mechanisms from the arid land environment and nearshore carbonate factory to the deep water. Since sedimentation on Bonaire is not hurricane-driven, the nearshore survey results clarify the drivers of sedimentation along the coast. The high-resolution seismic profiles make it possible to view the various topological features in the nearshore and to see the main sediment mechanisms in the region: gravity-driven downslope movement and mass transport. Deposition of sediment on Bonaire is unique because of the morphology of Bonaire's offshore slope, with only low levels of sediment accumulation in the modern reef, troughs (highest accumulation), and small-scale catchment basins within the valleys.
Using a sparker and marine streamer, we obtained high-frequency seismic profiles of the nearshore environment. In order to create a clear image of the subsurface, we used a trio of predictive deconvolutions in to minimize the bubble pulse and source and receiver ghosts. We will use this high-resolution dataset to connect the nearshore and slope environments to the deepwater basin imaged by a rescued legacy USGS seismic dataset from 1973. Rescue and open source access of these underutilized datasets is critical to understanding these environments with a seeming paucity of data.