Publications

During 2004-2006, the U.S. Geological Survey conducted a mineral resource assessment of selected areas administered by the Bureau of Land Management in Clark and Nye Counties, Nevada. The purpose of this study is to provide the BLM with information for land planning and management and, specifically, to determine mineral resource potential in accordance with regulations in 43 CFR 2310...

Integrated, multidisciplinary studies of the Handcart Gulch alpine watershed provide a unique opportunity to study and characterize the geology and hydrology of an alpine watershed along the Continental Divide. The study area arose out of the donation of four abandoned, deep mineral exploration boreholes to the U.S. Geological Survey for research purposes by Mineral Systems Inc. These...

The Virginia gold-pyrite belt, part of the central Virginia volcanic-plutonic belt, hosts numerous abandoned metal mines. The belt extends from about 50 km south of Washington, D.C., for approximately 175 km to the southwest into central Virginia. The rocks that comprise the belt include metamorphosed volcanic and clastic (noncarbonate) sedimentary rocks that were originally deposited...

The Mesa Formation extends from Cananea, Mexico, southeast to the Sonora River and is the main host rock of Laramide porphyry copper deposits in the Cananea District and at the Alacran porphyry prospect to the east. The Mesa consists of two members-a lower andesite and an upper dacite. The lowest part of the dacite member is a crystal tuff about 100 m thick. This tuff is the outfall of a...

We report the preliminary results of sequential partial dissolutions used to characterize the geochemical distribution of selenium in stream sediments, mine wastes, and flotation-mill tailings. In general, extraction schemes are designed to extract metals associated with operationally defined solid phases. Total Se concentrations and the mineralogy of the samples are also presented...

This report gives descriptions of the mineral occurrences in the Mount Katmai 1:250,000-scale quadrangle, Alaska. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska.

Freshwater diatomite deposits in the Western United States are found in lake beds that formed millions of years ago. These diatom-rich sediments are among the Nation's largest commercial diatomite deposits. Each deposit contains billions of tiny diatom skeletons, which are widely used for filtration, absorption, and abrasives. New studies by the U.S. Geological Survey (USGS) are...

This report describes a relational database containing information about mineral exploration projects in the States of Idaho and Montana for the years 1980 through 1997 and a spatial (geographic) database constructed using data from the relational database. The focus of this project was to collect information on exploration for mineral commodities with the exception of sand, gravel, coal

This report presents a map and database of Quaternary deposits and liquefaction susceptibility for the urban core of the San Francisco Bay region. It supercedes the equivalent area of U.S. Geological Survey Open-File Report 00-444 (Knudsen and others, 2000), which covers the larger 9-county San Francisco Bay region. The report consists of (1) a spatial database, (2) two small-scale...

No abstract available.

The presence of jarosite in soil or mining waste is an indicator of acidic sulfate-rich conditions. Physical and chemical properties of synthetic jarosites are commonly used as analogs in laboratory studies to determine solubility and acid-generation of naturally occurring jarosites. In our work we have mineralogically and chemically characterized both natural and synthetic jarosites...

Characterization of the physical and unsaturated hydrologic properties of subsurface materials is necessary to calculate flow and transport for land use practices and to evaluate subsurface processes such as perched water or lateral diversion of water, which are influenced by features such as faults, fractures, and abrupt changes in lithology. Input for numerical flow models typically...