MI-36 Bouguer Gravity Map of Colorado Download Publication Details Bouguer Gravity Map of Colorado with gravity stations and gravity contours (interval 5 milligals). USGS Map GP8951, Plate (1:500,000). Digital PDF download. MI-36D This black and white map was collaboratively produced between the U.S. Geological Survey (USGS), the Colorado Mining Industrial Development Board, and CGS in 1972. The gravity data was compiled from 14 sources. Citations Behrendt, J., and Lacretia Y. Bajwa. “MI-36 Bouguer Gravity Map of Colorado.” Bouguer Gravity. Miscellaneous Investigations. Denver, CO: Colorado Geological Survey and the Colorado Mining Industrial Development Board, 1972. https://coloradogeologicalsurvey.org/publications/bouguer-gravity-map-colorado-1972.