On the continental margin of northern California, north of the Mendocino triple junction, the geomorphic grain varies dramatically between the coast and the toe of the accretionary wedge. This grain represents the composite signature of three competing processes: tectonics, sedimentation and erosion. All three are active across the region, but their rates and orientations vary spatially and temporally, affecting the resultant grain and preservation potential in this rapid-sedimentation environment. At the toe of the accretionary wedge, the relative rate of tectonic deformation exceeds the rate of sediment accumulation, and erosion is largely limited to areally restricted (but at times large) mass-wasting features. In this region, isobaths (representing the geomorphic grain) are parallel to structural highs and lows, as in most forearcs, and sediment accumulation is restricted to small basins located between anticlinal ridges. The slope between the shelf break and the accretionary complex shows the competing effects of sediment accumulation, erosion and tectonism. Slope-perpendicular gullies are the prominent erosional features in this area, especially in the region surrounding the Trinity submarine canyon. Anticlinal ridges crop out on the seafloor, although the ridge crests decrease in bathymetric expression both up- and down-slope. On the shelf, the rate of sediment accumulation (6–12 mm/yr) exceeds the relative rate of tectonic deformation, with 1–3 mm/yr of active uplift on land. In this region, the geomorphic grain is controlled by sediment accumulation, with compressed but continuous stratigraphic sections above anticlinal highs and expanded sections in actively subsiding regions.