BY USING THIS WEBSITE OR THE CONTENT THEREIN, YOU AGREE TO THE TERMS OF USE. This polygon feature class represents the spatial extent of surficial geology deposits, glacial and sub-glacial drainage, and historical glacial lake shoreline areas in Oakland County. These features were captured using a combination of a surface TIN derived from 10-foot contours and a detailed original map of Oakland County surficial geology by Twenter and Knutilla, 1972. Polygons were delineated on a hard-copy map by John Zawiskie, Cranbrook geologist. The map was then scanned and registered to Oakland County GIS data. The polygons were digitized on-screen. Data was collected at approximately 1:1200; however the original map was produced at a countywide scale. The key attribute is the geologic sediment type.The primary business purpose for the development of this data set was to collaborate with the Cranbrook Institute of Science in producing an educational map about the surficial geology of Oakland County at a scale appropriate to Countywide and sub-County applications. Prior work by Farrand and Bell (1982) mapped surficial geology deposits of the entire state; however the data is too coarse to have meaningful application at a county and sub-County scale. An improved data set was created by combining Oakland's detailed digital topography with a more detailed geology map. Secondary business purposes include natural resources planning and environmental analysis. For example, this map was used to create an aquifer vulnerability map analysis as part of a countywide water resources study conducted by the United States Geological Survey.These features were captured using a combination of a surface TIN derived from 10-foot contours and a detailed original map of Oakland County surficial geology by Twenter and Knutilla, 1972. Polygons were delineated on a hard-copy map by John Zawiskie, Cranbrook geologist. The map was then scanned and registered to Oakland County GIS data. The polygons were digitized on-screen. Data was collected at approximately 1:1200; however the original map was produced at a countywide scale. Zawiskie QC'd the data through visual inspections of plots, and Nina Misuraca instituted the corrections.