Chandler, Val W.Ervin, C. PatrickVan De Voorde, B.W.Bouguer gravity anomaly map (anomaly related to different densities of rocks in the upper crust, Bouguer anomaly is a corrected difference between an observed gravity measurement and value predicted from a generalized earth model), shown as contour lines (isolines) of equal value, St. Paul quadrangle, scale 1:250,000.PDFengMinnesota Geological SurveyPublicSimple Bouguer gravity map of Minnesota, St. Paul sheet, M-48MapsMinnesota1980University of Minnesota