The Stratified Deposits data layer is part of a comprehensive study to produce a statewide digital map of the surficial geology at a 1:24,000-scale. This compilation of surficial geologic materials defines the areas of exposed bedrock, and the boundaries between glacial till, glacial stratified deposits, and overlying postglacial deposits. The stratified deposits layer shows areas of glacial stratified deposits categorized as Coarse, Glaciolacustrine Fine, and Glaciomarine Fine. This data layer should be used in conjunction with the underlying till bedrock data layer and the overlying early postglacial and postglacial data layers. MassGIS stores this layer as SURFGEO24K_SD_POLY.