DeWitt, Ed H.

About the author

U.S. Geological Survey, Central Region, Rocky Mountain area, Geology discipline
Abandoned mines and quarries, Aeromagnetic surveying, Aluminum, Antimony, Arsenic, Atomic absorption analysis, Atomic emission spectroscopy, Barium, Bedrock geologic units, Beryllium, Bismuth, Boron, Cadmium, Calcium, Carbon, Cerium, Cesium, Chemical analysis, Chlorine, Chromatography, Chromium, Cobalt, Continental lithosphere, Copper, Datasets, Dissolved metals, Dysprosium, Earth history, Ecology, Erbium, Europium, Fission-track dating, Fluorine, Gadolinium, Gallium, Geochemical processes, Geochemistry, Geochronology, Geologic history, Geologic maps, Geologic structure, Geology, Geophysics, Geospatial datasets, Germanium, Gold, Groundwater, Groundwater flow, Holmium, Iron, Isotopic analysis, Lanthanum, Lead, Liquid chromatography, Lithium, Lutetium, Macroinvertebrates, Magnesium, Magnetic field (earth), Manganese, Maps and atlases, Mass spectroscopy, Mathematical modeling, Metallic mineral resources, Metamorphic rocks, Metamorphism (geological), Mine drainage, Mineral deposits, Molybdenum, Neodymium, Nickel, Niobium, Nitrogen, Oxygen content (water), Petrology, Phosphorus, Plutonic rocks, Potassium, Potassium-argon analysis, Praseodymium, Rocks and deposits, Rubidium, Rubidium-strontium analysis, Salinity, Samarium, Scandium, Selenium, Silicon, Silver, Sinkhole formation, Sodium, Stratigraphic sections, Strontium, Sulfur, Tantalum, Terbium, Thallium, Thorium, Thulium, Tin, Titanium, Tracer study, Tungsten, Unconsolidated deposits, Uranium, Uranium-lead analysis, Vanadium, Water chemistry, Water pH, Water sampling, Water temperature, Ytterbium, Yttrium, Zinc, Zirconium, Faults, Folds (geologic), Mine sites, Mineral deposit areas, Parks, Granitoid, ArcInfo interchange, Geodatabase (ESRI), KML, Microsoft Access format, Microsoft Excel format, Portable Document Format, Comma-delimited text, File geodatabase (ESRI), Scientific application software, Shapefile, Tab-delimited text, GeoscientificInformation

Geologic and aeromagnetic maps of the Fossil Ridge area and vicinity, Gunnison County, Colorado

Geologic units, structural features, and aeromagnetic anomaly map of the area

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Map showing geology, structure, and geophysics of the central Black Hills, South Dakota

This 1:100,000-scale digital geologic map details the complex early Proterozoic granitic rocks, early Proterozoic supracrustal metamorphic rocks, and Archean crystalline basement of the Black Hills.

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Central Colorado Assessment Project (CCAP)-Geochemical data for rock, sediment, soil, and concentrate sample media

Chemical analysis of 47,478 samples of various geological materials to facilitate geologic mapping, petrologic studies, mineral resource assessment, and similar regional environmental assessements.

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Water and rock geochemistry, geologic cross sections, geochemical modeling, and groundwater flow modeling for identifying the source of groundwater to Montezuma Well, a natural spring in central Arizona

This report releases data, cross section, and model information related to the identification of travel paths for groundwater supply and principal stratigraphic and structural features that serve as constraints or conduits for groundwater movement.

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Geochronology Database for Central Colorado

Compilation of isotopic and fission track age determinations, some previously published. Data for the tephrochronology of Pleistocene volcanic ash, carbon-14, Pb-alpha, common-lead, and U-Pb determinations on uranium ore minerals are not included.

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Geochemical results from stream-water and stream-sediment samples collected in Colorado and New Mexico

Data from a study intended to explore how well the chemical analysis of water and sediment in an area reflects that of the rock from which the sediments are eroded and through which the water flows.

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Geochemical database for the Boulder Batholith and its satellitic plutons, southwest Montana

Geochemical analyses of Cretaceous igneous intrusions in order to establish the geologic framework for world-class mineral deposits of the Butte district

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Geospatial database for regional environmental assessment of central Colorado

Study focusing on the effects of historical mining on Forest Service lands in this area.

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Geochemical, modal, and geochronologic data for 1.4 Ga A-type granitoid intrusions of the conterminous United States

This report presents and makes data available to ongoing petrogenetic investigations of these rocks. It develops an accurate and current portrayal of their spatial distribution in GIS format while analyzed samples are presented via Excel workbooks.

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Basement domain map of the conterminous United States and Alaska

Seventy-seven major components of the North American continent were delineated at a general scale (1:5,000,000); including the general composition, geological environment, and types of primary metals endowments that can be expected in each domain.

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Basement domain map of the conterminous US and Alaska

Seventy-seven major components of the North American continent were delineated at a general scale (1:5,000,000); including the general composition, geological environment, and types of primary metals endowments that can be expected in each domain.

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