Geological analysis of planets typically begins with the construction of a geologic map of the planets' surfaces using remote data sets. Geologic maps provide the basis for interpretations of geologic histories, which in turn provide critical relations for understanding the range of processes that contributed to the evolution. Because geologic mapping should ultimately lead to the discovery of ...

First posted March 9, 2023 For additional information, contact: Contact Information,Geology, Minerals, Energy, & Geophysics Science Center Moffett FieldU.S. Geological Survey350 N. Akron Rd. P.O. Box 158 Field, CA 94035 This three-dimensional (3D) geologic map displays the subsurface geology in upper ~4 kilometers of Earth’s crust southeastern Gabbs Valley geothermal area west-central Nevada. T...

Although the origin and composition of many units are obscure or controversial, their interpretations are based on objective descriptions of morphologic characteristics visible on Viking photomosaics and images. LOWLAND TERRAIN MATERIALS Consist of all plains-forming units between the highland-lowland boundary scarp and the north edge of the map area, exclusive of materials of the western volca...

Controlled language is the primary challenge in merging heterogeneous databases of geologic information. Each agency or organization produces databases with different schema, and different terminology for describing the objects within. In order to make some progress toward merging these databases using current technology, we have developed software and a workflow that allows for the “manual sem...

The gravity and magnetic data measured on the Earth’s surface or above it (collected from an aircraft flying at low altitude) can be used to assist in geologic mapping by estimating the spatial density and magnetization distributions, respectively, presumably confined to the interior of a horizontal slab with known depths to the top and bottom. To estimate density or magnetization distributions...

The preliminary geologic map of the McTarnahan Hill quadrangle, first released in 1999 in PDF format, was originally drafted in Adobe Illustrator. This Second Edition (Revised 2009) was converted and modified slightly in ArcMap Version 9.3. The Quaternary unit descriptions were not significantly changed from the original map. Bedrock unit descriptions were modified and corrected, and sections w...

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

PLAINS MATERIALS pvs VERY SMOOTH PLAINS MATERIAL—Occurs as smooth planar surfaces only in floors of c 4 and c 5 craters (FDS 529126). Very few superposed craters at Mariner 10 resolutions. Interpretation: Probably shock-melt and fallback associated with formation of individual craters ps SMOOTH PLAINS MATERIAL—Forms flat to gently rolling plains in extremely large annulus surrounding Caloris Ba...