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Lorre A. Moyer

Publications and source records attributed to Lorre A. Moyer.

8 recordsLinked to original sources

Geologic map of the Patagonia Mountains, Santa Cruz County, Arizona

The Patagonia Mountains contain two large porphyry Cu-Mo systems each with separate associated hypogene and supergene zones, two high-grade Cu-Mo breccia pipes, one large epithermal Ag-Pb-Zn-Mn deposit, and numerous additional areas of base- and precious-metal mineralization all zoned around a Laramide-age composite batholith of intermediate composition. Compilations and new work by Vikre and others (2014) have identified as many as eight separate intrusive phases of the batholith and five separate hydrothermal events spanning at least 16 m.y., in addition to a supergene enrichment event of middle Tertiary age. The geologic map presents a spatial context for this important new information that is intended to support further work in this highly mineralized region. Several spatial databases provide data for the geologic map of the Patagonia Mountains in Arizona. The data can be viewed and queried in ArcGIS 10, a geographic information system; a geologic map is also available in PDF format. All products are available online only.

Arizona

Mining activity in Nevada, 1851-1995

This report describes a Microsoft PowerPoint digital movie package that displays patterns of Nevada mineral activity from 1851 to 1995 and historical factors that influenced these patterns. The digital package consists of a full length educational movie with text and two short animations showing the evolving patterns of significant Nevada mineral deposits and mining districts over selected decades. The movie was created from images that were exported from a geographic information system (GIS), Environmental Systems Research Institute (ESRI) ArcView 3.2.

Nevada

Spatial databases of the Humboldt Basin mineral resource assessment, northern Nevada

This report describes the origin, generation, and format of tract map databases for deposit types that accompany the metallic mineral resource assessment for the Humboldt River Basin, northern Nevada, (Wallace and others, 2004, Chapter 2). The deposit types include pluton-related polymetallic, sedimentary rock-hosted Au-Ag, and epithermal Au-Ag. The tract maps constitute only part of the assessment, which also includes new research and data for northern Nevada, discussions on land classification, and interpretation of the assessment maps. The purpose of the assessment was to identify areas that may have a greater favorability for undiscovered metallic mineral deposits, provide analysis of the mineral-resource favorability, and present the assessment of the Humboldt River basin and adjacent areas in a digital format using a Geographic Information System (GIS).

Open-File Report

Spatial digital database for the geologic map of Nevada

This report publishes a geologic digital spatial database (NVGEO) for the geologic map of Nevada by Stewart and Carlson (1978a) which was originally printed on a single sheet of paper at a scale of 1:500,000 (and later reprinted on two sheets in 1991). The spatial digital database (GIS) provided in this report supersedes earlier digital editions by Turner and Bawiec (1991) and Raines and others (1996).

Open-File Report

Chromite deposits in central part Stillwater Complex, Sweet Grass County, Montana: A digital database for the geologic map of the east slope of Iron Mountain

In 1940, A.L. Howland and J. W. Peoples, assisted by W.R. Jones and M.G. Bennett, mapped the geology of the east slope of Iron Mountain, Montana. The map was revised and extended by Howland in 1942 and published in 1955 as plate 10 of the U.S. Geological Survey Bulletin 1015-D (Howland, 1955). In 2000, the USGS contracted Optronics Specialty Co., Inc. of Northridge, CA to prepare a scanned digital version of plate 10. Geospatial editing and attributing of the scanned map of the east slope of Iron Mountain was performed by the USGS in order to produce an interim digital product. This digital geospatial database is one of many being created by the U.S. Geological Survey as an ongoing effort to provide geologic information in a geographic information system (GIS) for use in spatial analysis.

Montana

Preliminary digital map of cryptocrystalline occurrences in northern Nevada

The purpose was to identify potential cryptocrystalline material sources for tools used by indigenous people of the northern Nevada portion of the Great Basin. Cryptocrystalline occurrence data combed from the U.S. Geological Survey's Mineral Resources Data System (MRDS, 1995) were combined with sites described in Nevada rockhound guides and entered into a geographic information system (GIS). The map area encompasses northern Nevada (fig.1). This open-file report describes the methods used to convert cryptocrystalline occurrence data into a digital format, documents the file structures, and explains how to download the digital files from the U.S. Geological Survey's World Wide Web site. Uses of the spatial dataset include, but are not limited to, natural and cultural resource management, interdisciplinary activities, recreational rockhounding, and gold exploration. It is important to note that the accuracy of the spatial data varies widely, and for some purposes, field checks are advised.

Nevada