Map Releases

This digital map database is compiled from unpublished data and new mapping by the authors, represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database dilineate map units that are identified by age and lithology...

This digital map database is compiled from unpublished data and new mapping by the authors, represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database delineate map units that are identified by age and lithology...

No abstract available.

This digital geologic map compilation presents new polygon (i.e., geologic map unit contacts), line (i.e., fault, fold axis, and structure contour), and point (i.e., structural attitude, contact elevations) vector data for the Jasper 7 1/2' quadrangle in northern Arkansas. The map database, which is at 1:24,000-scale resolution, provides geologic coverage of an area of current...

No abstract available.

Introduction The Lavinia Planitia quadrangle (V-55) is in the southern hemisphere of Venus and extends from 25 to 50 south latitude and from 330 to 360 longitude. It covers the central and northern part of Lavinia Planitia and parts of its margins. Lavinia Planitia consists of a centralized, deformed lowland flooded by volcanic deposits and surrounded by Dione Regio to the west (Keddie...

This map uses Viking Orbiter image data and Viking 1 Lander image data to evaluate the geologic history of a part of Chryse Planitia, Mars. The map area lies at the termini of the Maja and Kasei Valles outwash channels and includes the site of the Viking 1 Lander. The photomosaic base for these quadrangles was assembled from 98 Viking Orbiter frames comprising 1204 pixels per line and...

Introduction The polar deposits on Mars probably record martian climate history over the last 107 to 109 years (for example, Thomas and others, 1992). The area shown on this map includes layered polar deposits and residual polar ice, as well as some exposures of older terrain. Howard and others (1982) noted that an area (at lat 84.8 S., long 356 W.) near a 23-km diameter impact crater...

Introduction The Magellan spacecraft orbited Venus from August 10, 1990, until it plunged into the Venusian atmosphere on October 12, 1994. Magellan had the objectives of (1) improving knowledge of the geologic processes, surface properties, and geologic history of Venus by analysis of surface radar characteristics, topography, and morphology and (2) improving knowledge of the geophysics...

New 1:24,000-scale geologic map of the Rifle Falls 7.5' quadrangle, in support of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of the stratigraphy, structure, and geologic hazards in the area of the southwest flank of the White River uplift. Bedrock strata include the Upper Cretaceous Iles Formation through Ordovician and...

This map was prepared as a collaborative effort with the Missouri Division of Geology and Land Survey, the Kansas Geological Survey, and the Nebraska Conservation and Survey Division. Map units and preliminary contacts between units were identified using stereoscopic pairs of high altitude, false color infrared, aerial photographs. Contacts were drawn on twelve USGS 7.5-minute...

New 1:24,000-scale geologic mapping in the Silt 7.5' quadrangle, in support of the USGS Western Colorado I-70 Corridor Cooperative Geologic Mapping Project, provides new interpretations of the stratigraphy, structure, and geologic hazards in the area of the southwest flank of the White River uplift, the Grand Hogback, and the eastern Piceance Basin. The Wasatch Formation was subdivided...