The U.S. Geological Survey conducted a program of bedrock geologic mapping in much of the central and western upper peninsula of Michigan and parts of Wisconsin from the 1940’s until the late 1990’s. Geologic studies in this region are hampered by a scarcity of bedrock exposures because of a nearly continuous blanket of unconsolidated sediments resulting from glaciation of the region during the Pleistocene ice ages. The USGS mapping, done largely at a scale of 1:24,000, routinely recorded the location and extent of exposed bedrock to provide both an indication of where direct observations were made, and as a guide for future investigations to expedite location of observable rock exposures. The locations of outcrops were generally shown as colored or patterned overlays on printed geologic maps. Although those maps have been scanned and are available as PDF files, no further digital portrayal of the outcrops has been done. We have conducted a prototype study of digitizing and improving locational accuracy of the outcrop locations in parts of Dickinson County, Michigan, to form a data layer that can be used with other data layers in GIS applications.

Digital Data from VG98-330A Ratcliffe, N.M., and Walsh, G. J., 1998,�Digital and preliminary bedrock geologic map of the Mount Carmel quadrangle, Vermont: USGS Open-File Report 98-330-A, 1 plate, scale 1:24000. The bedrock geologic map data at a scale of 1:24,000 depicts types of bedrock underlying unconsolidated materials in Vermont. Data is created by mapping on the ground using standard geologic pace and compass techniques and/or GPS on a USGS 1:24000 topographic base map. Data may be organized by town, quadrangle or watershed. Each data bundle may includes point, line and polygon data and some or all of the following: 1) contacts (lithogic contacts), 2) fault_brittle, 3) fault_ductile, 4) fault_thrust, 5) fault_bed_plane (bedding plane thrust), 6) bedding, 7) bedding_graded (graded bedding) 8) bedding_overturn (overturned bedding), 9) bedding_select (selected points for published map), 10) foliation_n1, n2, n3 etc (foliation data), 11) outcrop (exposed outcrops), 12) field_station (outcrop and data collection point), 13) fold_axis, 14) axial_plane, 15) lamprophyre, 16) water_well_log (water well driller information), 16) linear_int (intersection lineation), 17) linear_str (stretching lineation) 18) x_section_line (line of cross-section), and photolinear (lineaments identified from air photos). Other feature classes may be included with each data bundle. (https://dec.vermont.gov/geological-survey/publication-gis/ofr).

The U.S. Geological Survey (USGS) collected rock density measurements to help understand causative sources of gravity survey anomalies in the Iron Mountain-Menominee region, Michigan-Wisconsin. The measurements were determined from rock samples collected on outcrop and in drill core. The measurements facilitate the interpretation of gravity anomalies and help map the distribution of Precambrian rocks in the region.

The U.S. Geological Survey (USGS) collected rock density measurements to help understand causative sources of gravity survey anomalies in the Iron Mountain-Menominee region, Michigan-Wisconsin. The measurements were determined from rock samples collected on outcrop and in drill core. The measurements facilitate the interpretation of gravity anomalies and help map the distribution of Precambrian rocks in the region.

Digital Data from VG95-5A Stanley, R, DelloRusso, V, Haydock, S, Lapp, E, O'Loughlin, S, Prewitt, J,and Tauvers, PR, 1995, Digital compilation bedrock geologic map of the Lincoln quadrangle, Vermont: VGS Open-File Report VG95-5A, 2 plates, scale 1:24000. The bedrock geologic map data at a scale of 1:24,000 depicts types of bedrock underlying unconsolidated materials in Vermont. Data is created by mapping on the ground using standard geologic pace and compass techniques and/or GPS on a USGS 1:24000 topographic base map. Data may be organized by town, quadrangle or watershed. Each data bundle may includes point, line and polygon data and some or all of the following: 1) contacts (lithogic contacts), 2) fault_brittle, 3) fault_ductile, 4) fault_thrust, 5) fault_bed_plane (bedding plane thrust), 6) bedding, 7) bedding_graded (graded bedding) 8) bedding_overturn (overturned bedding), 9) bedding_select (selected points for published map), 10) foliation_n1, n2, n3 etc (foliation data), 11) outcrop (exposed outcrops), 12) field_station (outcrop and data collection point), 13) fold_axis, 14) axial_plane, 15) lamprophyre, 16) water_well_log (water well driller information), 16) linear_int (intersection lineation), 17) linear_str (stretching lineation) 18) x_section_line (line of cross-section), and photolinear (lineaments identified from air photos). Other feature classes may be included with each data bundle. (https://dec.vermont.gov/geological-survey/publication-gis/ofr).

Digital Data from VG98-335A Burton, WC, and Ratcliffe, NM, 2000, Digital and preliminary bedrock geologic map of the Wallingford quadrangle, Vermont: USGS Open-File Report 99-337-A, scale 1:24000 The bedrock geologic map data at a scale of 1:24,000 depicts types of bedrock underlying unconsolidated materials in Vermont. Data is created by mapping on the ground using standard geologic pace and compass techniques and/or GPS on a USGS 1:24000 topographic base map. Data may be organized by town, quadrangle or watershed. Each data bundle may includes point, line and polygon data and some or all of the following: 1) contacts (lithogic contacts), 2) fault_brittle, 3) fault_ductile, 4) fault_thrust, 5) fault_bed_plane (bedding plane thrust), 6) bedding, 7) bedding_graded (graded bedding) 8) bedding_overturn (overturned bedding), 9) bedding_select (selected points for published map), 10) foliation_n1, n2, n3 etc (foliation data), 11) outcrop (exposed outcrops), 12) field_station (outcrop and data collection point), 13) fold_axis, 14) axial_plane, 15) lamprophyre, 16) water_well_log (water well driller information), 16) linear_int (intersection lineation), 17) linear_str (stretching lineation) 18) x_section_line (line of cross-section), and photolinear (lineaments identified from air photos). Other feature classes may be included with each data bundle. (https://dec.vermont.gov/geological-survey/publication-gis/ofr).

Digital Data from VG95-4A Walsh, GJ, Haydock, S, Prewitt, J, Kraus, J, Lapp, E, O'Loughlin, S, and Stanley, RS, 1995, Digital compilation bedrock geologic map of the Warren quadrangle, Vermont: VGS Open-File Report VG95-4A, 2 plates, scale 1:24000. The bedrock geologic map data at a scale of 1:24,000 depicts types of bedrock underlying unconsolidated materials in Vermont. Data is created by mapping on the ground using standard geologic pace and compass techniques and/or GPS on a USGS 1:24000 topographic base map. Data may be organized by town, quadrangle or watershed. Each data bundle may includes point, line and polygon data and some or all of the following: 1) contacts (lithogic contacts), 2) fault_brittle, 3) fault_ductile, 4) fault_thrust, 5) fault_bed_plane (bedding plane thrust), 6) bedding, 7) bedding_graded (graded bedding) 8) bedding_overturn (overturned bedding), 9) bedding_select (selected points for published map), 10) foliation_n1, n2, n3 etc (foliation data), 11) outcrop (exposed outcrops), 12) field_station (outcrop and data collection point), 13) fold_axis, 14) axial_plane, 15) lamprophyre, 16) water_well_log (water well driller information), 16) linear_int (intersection lineation), 17) linear_str (stretching lineation) 18) x_section_line (line of cross-section), and photolinear (lineaments identified from air photos). Other feature classes may be included with each data bundle. (https://dec.vermont.gov/geological-survey/publication-gis/ofr).

During the 2017 field season, geologists from the Alaska Division of Geological & Geophysical Surveys (DGGS) conducted geologic mapping and sampling of part of the Richardson mining district southeast of Fairbanks, Alaska. The project area is about 30 miles west of the Pogo gold mine and covers gold exploration activity at the Montecristo and Uncle Sam properties. This work aims to build an improved understanding of the area's geology and controls on gold mineralization for purposes of exploration targeting and mineral-resource assessment. The 260-square-mile map area lies between the Salcha River and Shaw Creek and is bounded by the Trans-Alaska Pipeline access road to the southwest. The area is characterized by forested, moderate-relief hills blanketed by vegetation, loess, and locally, sand dunes. Rock outcrop is less than one percent; consequently, the map interpretation relies heavily on the DGGS East Richardson airborne magnetic and electromagnetic survey as well as rocks collected from pits dug into rocky colluvial deposits below surficial loess or sand. The complete report, geodatabase, and ESRI fonts and style files are available from the DGGS website: http://doi.org/10.14509/30676.

Digital Data from VG98-335A Armstrong, T.R., and Ratcliffe, N.M., 1998, Digital and preliminary bedrock geologic map of the Townshend 7.5 x 15 minute quadrangle, Vermont: USGS Open-File Report 98-335-A, 1 plate, scale 1:24000. The bedrock geologic map data at a scale of 1:24,000 depicts types of bedrock underlying unconsolidated materials in Vermont. Data is created by mapping on the ground using standard geologic pace and compass techniques and/or GPS on a USGS 1:24000 topographic base map. Data may be organized by town, quadrangle or watershed. Each data bundle may includes point, line and polygon data and some or all of the following: 1) contacts (lithogic contacts), 2) fault_brittle, 3) fault_ductile, 4) fault_thrust, 5) fault_bed_plane (bedding plane thrust), 6) bedding, 7) bedding_graded (graded bedding) 8) bedding_overturn (overturned bedding), 9) bedding_select (selected points for published map), 10) foliation_n1, n2, n3 etc (foliation data), 11) outcrop (exposed outcrops), 12) field_station (outcrop and data collection point), 13) fold_axis, 14) axial_plane, 15) lamprophyre, 16) water_well_log (water well driller information), 16) linear_int (intersection lineation), 17) linear_str (stretching lineation) 18) x_section_line (line of cross-section), and photolinear (lineaments identified from air photos). Other feature classes may be included with each data bundle. (https://dec.vermont.gov/geological-survey/publication-gis/ofr).

Digital Data from VG94-229A Walsh, G.J., Ratcliffe, N.M., Dudley, J.B., and Merrifield, T., 1994,�Digital bedrock geologic map of the Mount Holly and Ludlow quadrangles, Vermont: USGS Open-File Report 94-229, 2 plates, scale 1:24000. The bedrock geologic map data at a scale of 1:24,000 depicts types of bedrock underlying unconsolidated materials in Vermont. Data is created by mapping on the ground using standard geologic pace and compass techniques and/or GPS on a USGS 1:24000 topographic base map. Data may be organized by town, quadrangle or watershed. Each data bundle may includes point, line and polygon data and some or all of the following: 1) contacts (lithogic contacts), 2) fault_brittle, 3) fault_ductile, 4) fault_thrust, 5) fault_bed_plane (bedding plane thrust), 6) bedding, 7) bedding_graded (graded bedding) 8) bedding_overturn (overturned bedding), 9) bedding_select (selected points for published map), 10) foliation_n1, n2, n3 etc (foliation data), 11) outcrop (exposed outcrops), 12) field_station (outcrop and data collection point), 13) fold_axis, 14) axial_plane, 15) lamprophyre, 16) water_well_log (water well driller information), 16) linear_int (intersection lineation), 17) linear_str (stretching lineation) 18) x_section_line (line of cross-section), and photolinear (lineaments identified from air photos). Other feature classes may be included with each data bundle. (https://dec.vermont.gov/geological-survey/publication-gis/ofr).