Includes deposits of unconsolidated particles of biogenic or mineral sediments with a dominant particle size ranging from 0.0625-2.0 millimeters in diameter; the deposits may be located offshore as sand beds or onshore as dunes and beaches. Distributions are recorded observations or models of sediment size, composition, and deposit thickness in a location or area, including maps of sand resources compiled through observations, interpreted data, remote sensing data, geologic maps, and hydrodynamic models. Assessments are evaluations of total sand availability; models of present sand deposition and resuspension rates; models of difficulty of extraction, relocation, or protection; and models of ecological and economic value. Predictions are the results of models or projections of future distributions, values, or ecological impacts of sand resources; these data include predicted changes to sand beds due to natural and human forces; scenario-based models of sand resource losses or gains under different management strategies of mining, extraction, relocation, dredging-related deposition, beach nourishment, or hard structure placement (for example, on beaches); and projections of the effects of human alterations to sand resources on other resources or on ecological function.