Publications

Introduction: This map and associated digital databases are the result of a compilation and reinterpretation of published and unpublished 1:250,000- and limited 1:125,000- and 1:63,360-scale mapping. The map area covers approximately 416,000 sq km (134,000 sq mi) and encompasses 25 1:250,000-scale quadrangles in central Alaska. The compilation was done as part of the U.S. Geological...

No abstract available.

The Payette National Forest (PNF), in west-central Idaho, is geologically diverse and contains a wide variety of mineral resources. Mineral deposit types are grouped into locatable, leasable, and salable categories. The PNF has substantial past production and identified resources of locatable commodities, including gold, silver, copper, zinc, tungsten, antimony, mercury, and opal. Minor...

This report describes a digital map and data files generated by the U.S. Geological Survey (USGS) to provide digital spatial mining claim information for Federal lands in Montana as of March, 1997. Statewide, 159,704 claims had been recorded with the Bureau of Land Management since 1975. Of those claims, 21,055 (13%) are still actively held while 138,649 (87%) are closed and are no...

MORPH-I is a set of C-language computer programs for the IBM PC and compatible minicomputers. The programs in MORPH-I are used for the fractal analysis of scanning electron microscope and electron microprobe images of pore profiles exposed in cross-section. The program isolates and traces the cross-sectional profiles of exposed pores and computes the Richardson fractal dimension for each...

This summary of international nonfuel mineral exploration activities for 1997 draws upon available data from literature, industry and US Geological Sulvey (USGS) specialists. Data on exploration budgets by region and commodity are reported, significant mineral discoveries and exploration target areas are identified and government programs affecting the mineral exploration industry are...

Part of a special section on the state of industrial minerals in 1997. The state of the asbestos industry in 1997 is discussed. World production of asbestos in 1997 was estimated to be 2.07 Mt. Consumption in the U.S. fell 3 percent to 21 kt, and it is expected to continue to decline at a rate of 2–4 percent per year.

This report presents porewater and selected water column data collected from Coeur d'Alene Lake in September of 1992. Despite probable oxidation of the porewater samples during collection and handling, these data are used to calculate molecular diffusive fluxes of dissolved metals (that is, Zn, Pb, Cu, and Mn) across the sediment-water interface. While these data and calculations provide

Published on an annual basis, this report is the earliest Government publication to furnish estimates covering nonfuel mineral industry data. Data sheets contain information on the domestic industry structure, Government programs, tariffs, and 5-year salient statistics for over 90 individual minerals and materials.

This map database represents the integration of previously published and unpublished maps by several workers (see Sources of Data index map on Sheet 2 and the corresponding table below) and new geologic mapping and field checking by the authors with the previously published geologic map of San Mateo County (Brabb and Pampeyan, 1983) and Santa Cruz County (Brabb, 1989, Brabb and others...

No abstract available.

The confidence parameters in Table 5 and Figures 7 -12 in Bakun and Wentworth (1997) were calculated using the site corrections for MI(4) rather than Bakun and Wentworth's (1997) preferred relation MI(3). The conclusions of Bakun and Wentworth (1997) are not changed by these corrections. The corrected Table 5 and Figures are in this report and at http://quake.wr.usgs.gov/~bakun/.