Extensive high-resolution, multibeam bathymetry of five U.S. continental margins provides new, detailed information about the angle of continental slopes in different sedimentary and tectonic settings. The steepest continental slope examined is the passive-carbonate west Florida slope (4.4 degrees regional slope and 12.0 degrees mean local slope). The steepest of the four elastic continental slopes is the passive New Jersey-Maryland slope (2.5 degrees and 7.6 degrees). Less steep, at both regional and local scales, are the more rugged, tectonically active and probably unstable salt-tectonized Louisiana slope (0.5 degrees and 2.9 degrees), strike-slip California slope (1.8 degrees and 5.2 degrees) and convergent Oregon slope (2.0 degrees and 5.2 degrees). Frequency grids of local slope magnitude vs. depth and dip direction for the two passive continental slopes reflect present-day morphology predominantly being shaped by lithology (west Florida), sedimentation (New Jersey-Maryland), and downslope-directed erosion (New Jersey-Maryland, west Florida). The grids for the three tectonically active continental slopes reflect morphology partly (California) to predominantly (Louisiana, Oregon) being shaped by tectonics.
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