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United States Geological Survey

Publications and source records attributed to United States Geological Survey.

25 records · Page 2Linked to original sources
USGS1973

Atlas of Mars, MC-18, Coprates Quadrangle

This mosaic was made with Mariner 9 pictures provided by the Jet Propulsion Laboratory (JPL), California Institute of Technology. The Image Processing Laboratory (IPL) of JPL processed the digital pictures to remove image artifacts and geometric distortions, to enhance high-frequency topographic detail while subduing low-frequency albedo variation, and to transform the pictures to a Mercator projection. The U.S. Geological Survey performed further artifact removal and modified contrast and tone of each picture analytically on the digital magnetic tapes provided by IPL for uniformity of tone and contrast within the mosaic. Photographic reproductions of the pictures were generated from the magnetic tapes and mosaicked by the U.S. Geological Survey.

Open-File Report↗
USGS1973

Atlas of Mars, Sinus Sabaeus Quadrangle, MC-20

This mosaic was made with Mariner 9 pictures provided by the Jet Propulsion Laboratory (JPL), California Institute of Technology. The Image Processing Laboratory (IPL) of JPL processed the digital pictures to remove image artifacts and geometric distortions, to enhance high-frequency topographic detail while subduing low-frequency albedo variation, and to transform the pictures to a Mercator projection. The U.S. Geological Survey performed further artifact removal and modified contrast and tone of each picture analytically on the digital magnetic tapes provided by IPL for uniformity of tone and contrast within the mosaic. Photographic reproductions of the pictures were generated from the magnetic tapes and mosaicked by the U.S. Geological Survey. Primary horizontal control points, where available, controlled the placement of pictures. Where these points were not available, picture placement was controlled by spacecraft tracking data and by matching images in overlap zones between pictures. Discrepancies in matching these images are less than 10 km over 90% of the mosaic. The number designations and positions of the primary control points, shown by broken crosses (-l-), are those given by Davies and Arthur (1973). Aerographic latitudes are shown on this mosaic. The projection is based on a theoretical dynamical ellipticity of 1/192. The scale is based on an equatorial radius of 3393. 4 km.

Open-File Report↗
USGS1973

Atlas of Mars, Iapygia Quadrangle, MC-21

This mosaic was made with Mariner 9 pictures provided by the Jet Propulsion Laboratory (JPL), California Institute of Technology. The Image Processing Laboratory (IPL) of JPL processed the digital pictures to remove image artifacts and geometric distortions, to enhance high-frequency topographic detail while subduing low-frequency albedo variation, and to transform the pictures to a Mercator projection. The U.S. Geological Survey performed further artifact removal and modified contrast and tone of each picture analytically on the digital magnetic tapes provided by IPL for uniformity of tone and contrast within the mosaic. Photographic reproductions of the pictures were generated from the magnetic tapes and mosaicked by the U.S. Geological Survey. Primary horizontal control points, where available, controlled the placement of pictures. Where these points were not available, picture placement was controlled by spacecraft tracking data and by matching images in overlap zones between pictures. Discrepancies in matching these images are less than 10 km over 90% of the mosaic. The number designations and positions of the primary control points, shown by broken crosses (-l-), are those given by Davies and Arthur (1973). Aerographic latitudes are shown on this mosaic. The projection is based on a theoretical dynamical ellipticity of 1/192. The scale is based on an equatorial radius of 3393. 4 km.

Open-File Report↗
USGS1973

Alas of Mars chart, Mare Tyrrhenum Quadrangle, MC-22

This mosaic was made with Mariner 9 pictures provided by the Jet Propulsion Laboratory (JPL), California Institute of Technology. The Image Processing Laboratory (IPL) of JPL processed the digital pictures to remove image artifacts and geometric distortions, to enhance high-frequency topographic detail while subduing low-frequency albedo variation, and to transform the pictures to a Mercator projection. The U.S. Geological Survey performed further artifact removal and modified contrast and tone of each picture analytically on the digital magnetic tapes provided by IPL for uniformity of tone and contrast within the mosaic. Photographic reproductions of the pictures were generated from the magnetic tapes and mosaicked by the U.S. Geological Survey. Primary horizontal control points, where available, controlled the placement of pictures. Where these points were not available, picture placement was controlled by spacecraft tracking data and by matching images in overlap zones between pictures. Discrepancies in matching these images are less than 10 km over 90% of the mosaic. The number designations and positions of the primary control points, shown by broken crosses (-l-), are those given by Davies and Arthur (1973). Aerographic latitudes are shown on this mosaic. The projection is based on a theoretical dynamical ellipticity of 1/192. The scale is based on an equatorial radius of 3393. 4 km.

Open-File Report↗
USGS1945

Topographic and geologic maps of manganese deposits in California

Geologic and topographic maps of several manganese properties in California were released today by the Geological Survey according to an announcement made by Survey Director W. E. Wrather to Secretary of the Interior Harold L. Ickes. The maps have been placed on open file at the offices of the Geological Survey in Washington, D. C., and at the offices of the Geologic Branch, California Division of Mines, Ferry Building, San Francisco, where they may be consulted by persons directly interested in the properties. The recently increased demand for information regarding deposits of manganese silicates for new uses in connection with the war effort has indicated the desirability of releasing unpublished detailed maps of the California deposits, many of which carry manganese silicates. The maps were made as part of the strategic minerals investigations of the Geological Survey from 1941 to 1943. The deposits covered by the maps are in the following counties of California: Amador, Calaveras, Eldorado, Glenn, Humboldt, Los Angeles, Madera, Mariposa, Mendocino, Mono, Placer, Plumas, San Bernardino, San Benito, San Luis Obispo, San Joaquin, Sonoma, Stanislaus, Trinity, and Tuolumne.

California↗