Knowledge of the distribution, concentration, and composition of suspended particulate matter in seawater is important to the understanding of sedimentation processes on the Continental Shelf. Because the surfaces of both organic and inorganic particles have high affinities for pollutants, such as certain trace metals, chlorinated hydrocarbons, and petroleum (Bothner et al., 1981a), suspended matter plays a major role in the transport and fate of pollutants introduced into shelf and coastal waters. Although the composition of bottom sediments on the shelf off the northeastern United States is reasonably well known, the mineralogical composition and distribution of inorganic suspended matter is less well studied.