Winter 1992

NBMG is using geographic information system (GIS) technology to study and disseminate information relating to geology, mineral resources, and geologic hazards of Nevada. A GIS is a system of computer hardware, software, and procedures designed to support efficient capture, management, manipulation, analysis, modeling, and display of spatially referenced data. NBMG is currently using ARC/INFO GIS software running on three SUN work stations and three PC DOS machines. The following are some ongoing or recently completed projects that have used NBMG's GIS capabilities for digital analysis and/or cartographic production.

NBMG has initiated two new statewide GIS projects. One is a series of 1:1,000,000-scale commodity maps, starting with a Digital Oil and Gas Well Map of Nevada. Attributes of this data set include operator and well name, well location, total depth, well status, and oil/gas shows. The next map in the series will be a digital version of the new Mining Districts of Nevada Map shown on the front page of this newsletter. This map will consist of a mining district polygon coverage attributed with district name, alternate names, and primary commodities produced. Both digital maps will be available by the end of 1992 and will include county boundaries, township and range, and major road network. Two other 1:1,000,000-scale digital map products are currently planned for release early next year: Active Mines Map of Nevada and Industrial Minerals Map of Nevada. When these maps are completed they will be available for purchase as hardcopy maps or as digital files in DXF or ARC/INFO export file format.

One project, recently completed, is the subsidence project in Las Vegas Valley, Nevada. The goal of the subsidence project was to document, map, and delineate existing subsidence and areas with a high probability of future subsidence. This project required the integration of geology, faults, soils, soil compaction data, amount of existing subsidence, historical elevation data, and current elevation data obtained by using Global Positioning System (GPS) technology. This data set was digitized from 1:24,000-scale source material and is available in an ARC/INFO export format.

A project to inventory sand and gravel resources in the Las Vegas Valley and Pahrump Valley areas has been completed. This project produced four layers of digital information: a geology map, an urbanization map, a resource map, and a map of current operations. These maps were produced at 1:100,000 scale and are available in digital format. A similar project has been completed for southern Washoe County.

NBMG, in cooperation with the Nevada Division of Health, is conducting a statewide indoor radon survey to characterize areas of high radon potential. The finished product will be a 1:500,000-scale map of potential radon hazards in the state. Coverages being used or created for this project include geology, soils, radioactivity in groundwater, climatological data, indoor radon sample site data, and results from the National Uranium Resource Evaluation (NURE) for the state of Nevada. A second part of the radon survey will consist of a more detailed study of the Reno/Carson City area and the Las Vegas Valley area at 1:100,000 scale. The purpose of this study is to determine the variation of radon potential within a community. NBMG also maintains several databases:
DB3 -- Nevada oil and gas well catalog;
DB6 -- Nevada oil and gas source-rock database;
DB7 -- Nevada mineral reserves and resources database; and
DB8 -- Geochemical analyses of over 4200 samples collected by NBMG.

These databases are available as digital files in dBASE III+ format or as printouts. Please see the NBMG 1992-93 publications list, available free on request, for further information and cost of these database products.

These projects, both short and long term, are being used to construct and expand our overall GIS database. Development, utilization, and expansion of this database will continue into the foreseeable future as one of our main goals. If you have any questions about the availability of these data or about our GIS lab please call me at (702) 784-6691.

---Ron Hess, Geologic Information Specialist