Geochemical processes

Processes affecting the amount, distribution, or structure of chemical elements in air, water, soil, rocks, and minerals.
Subtopics:
Biodegradation (1 items)
Ore formation (20 items)
Sorption (2 items)


Results listed alphabetically [list by similarity]
Alkalic-type epithermal gold deposit model; Chapter R in Mineral deposit models for resource assessment

Summarizes the primary characteristics of alkalic-type epithermal gold deposits and provides an updated descriptive model, including geologic setting and processes, associated deposit types and commodities, Discusses examples of this type.

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Alteration, slope-classified alteration, and potential lahar inundation maps of volcanoes for the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Volcano Archive

Identifies hydrothermally altered volcanic edifices and vulnerable areas downstream by mapping alteration on volcanoes, highlighting lahar prone watersheds using Global Digital Elevation Model data, and modeling via a lahar flow-fill modeling program

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Climax-type porphyry molybdenum deposits

Descriptive mineral deposit model, with locations of known deposits of this type and a few site characteristics.

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Data to accompany U.S. Geological Survey Data Series 1099: Petrographic, geochemical and geochronologic data for Cenozoic volcanic rocks of the Tonopah, Divide, and Goldfield Mining Districts, Nevada

Geochemical, petrographic, and geochronologic data for samples, principally those of unmineralized Tertiary volcanic rocks, from the Tonopah, Divide, and Goldfield mining districts of west-central Nevada.

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Electron Probe Microanalyses of apatite, rutile, and titanite from stream sediment and rock samples in the eastern Tanacross quadrangle, eastern Alaska

Electron probe data collected for apatite, rutile, and titanite to fingerprint porphyry-style mineralization near the Taurus deposit in eastern Alaska. Data are provided in CSV format.

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Field and Laboratory data of pipe scale forming in acid mine drainage pipelines at Iron Mountain and Leviathan Mines, California

Data from pipelines from 2012-2015, includes water chemistry of the acid mine drainage, mineralogy of pipe scale (by X-ray diffraction and chemical extractions), and laboratory experiment results. Data are provided in CSV format.

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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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Geochronology and geology of late Oligocene through Miocene volcanism and mineralization in the western San Juan mountains, Colorado

New age determinations with descriptions of sample locations and analytical details.

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Giant porphyry-related metal camps of the world

Database of large-tonnage, generally low-grade, hydrothermal deposits related to igneous intrusions emplaced at high crustal levels. Includes tri-partite classification based on deposit type, metal commodities, and source/host pluton chemistry.

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In situ geochemical data related to the gold-quartz veins of Grass Valley, California, 2014-2015

Geochemical data for pyrite crystals and native gold from two distinct vein sets in this area to better understand paragenesis of quartz veins in orogenic gold deposits. Data are provided in CSV format.

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Isotope and chemical data for: Sulfur isotopes of host strata for Howards Pass (Yukon-Northwest Territories) Zn-Pb deposits implicate anaerobic oxidation of methane not basin stagnation

Sulfur and carbon isotope compositions, concentrations of selected elements, and concentrations of pyrite sulfur and organic carbon in mudstone samples collected from five cores drilled in this area. Data are provided in CSV format.

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Linking geology and health sciences to assess childhood lead poisoning from artisanal gold mining in Nigeria

Approximately 400 young children have died and thousands more are affected. This study clarifies lead sources and exposure pathways, identifies other toxicants of concern and people at risk, and examines potential for similar lead poisoning globally.

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Low-fluorine stockwork molybdenite deposits

Descriptive mineral deposit model, with locations of known deposits of this type and a few site characteristics.

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Mapping the mineral resource base for mineral carbon-dioxide sequestration in the conterminous United States

Map includes GIS data for magnesium-rich ultramafic rocks

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Mineral resource data for Mississippi Valley-Type and clastic-dominated sediment-hosted lead-zinc deposits

Map interface and data download of Sed Zn-Pb data including KML and GIS data formats

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Porphyry copper deposits of the world

Information on porphyry copper deposits from around the world with grade and tonnage models, a general classification based on geologic setting, mineralogy, with data allowing locations of these deposits to be plotted using GIS.

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Porphyry copper deposits of the world; database and grade and tonnage models, 2008

Revised and updated information about mineral deposit models for porphyry copper deposits to facilitate assessment of undiscovered resources

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Porphyry copper deposits of the world: database, map, and grade and tonnage models

A compilation of worldwide mineral deposits of this type. This older version was revised and updated in OFR-2008-1155.

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Porphyry copper deposits of the world: database, maps, and preliminary analysis

A compilation of worldwide mineral deposits of this type. This older version was revised and updated in OFR-2008-1155.

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Re-Os Geochronologic Data for Porphyry Deposits in the Yukon-Tanana Upland, Eastern Alaska

Isotopic composition and calculated geochronology in order to date the mineralizing events in these hydrothermal systems. Data are provided in CSV format.

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Sediment-hosted zinc-lead deposits of the world

Map interface and data download of Sed Zn-Pb data including KML and GIS data formats

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Selected geochemical data for modeling near-surface processes in mineral systems

Data on a variety of mineral deposit types that have variable environmental effects when exposed at the ground surface by mining or natural processes.

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Sequential extraction results and mineralogy of mine waste and stream sediments associated with metal mines in Vermont, Maine, and New Zealand

Results from sequential extraction experiments and the quantitative mineralogy for samples of stream sediments and mine wastes collected from metal mines.

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Surface mineral maps of Afghanistan derived from HyMap imaging spectrometer data, version 2

The report presents new maps from data collected in 2007 and the processing steps applied to that data. The maps are being used for natural resource development and to prioritize study areas of mineral distribution to assist with economic revitalization.

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Systems-deposits-commodities-critical minerals table for the earth mapping resources initiative

Describes the rationale for, and structure of, a table developed for Earth MRI that relates critical minerals and principal commodities to the deposit types and mineral systems in which they are concentrated. The hierarchical relationship between systems, deposits, commodities, and critical minerals makes it possible to define and prioritize each system-based focus area once for all of the critical minerals that it may contain.

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U-Pb SHRIMP and 40Ar/39Ar geochronologic data and backscatter electron (BSE) and panchromatic cathodoluminescent (CL) imagery of sample materials for study of dikes, country rock, and alteration systems, Butte, U.S.A.

Geochronological data using several different techniques, for a multidisciplinary study of dikes, country rock, and alteration systems in which mineral deposits may form. Data are provided in Esri file geodatabase, shapefile, Microsoft Excel, and CSV formats.

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Update of the Mineral Resources Data System for California including Mineral Deposit Types

Improved information on deposit model (type) in records of this older USGS database describing sites that are located in California. Includes a list of additional deposit types needed to properly categorize the California locations. Data are provided in Microsoft Excel, CSV, and Esri personal geodatabase (Microsoft Access) formats.

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Volcanogenic massive sulfide deposits of the world

Map interface and data download of VMS data including KML and GIS data formats

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Volcanogenic massive sulfide deposits of the world; database and grade and tonnage models

Information on VMS deposits from around the world with new grade and tonnage models for three subtypes of VMS deposits and data allowing locations of all deposits to be plotted using GIS.

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