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R. R. Wahl

Publications and source records attributed to R. R. Wahl.

7 recordsLinked to original sources

Digital geologic map database of the Nevada Test Site area, Nevada

Forty years of geologic investigations at the Nevada Test Site (NTS) have been digitized. These data include all geologic information that: (1) has been collected, and (2) can be represented on a map within the map borders at the map scale is included in the map digital coverages. The following coverages are included with this dataset: Coverage Type Description geolpoly Polygon Geologic outcrops geolflts line Fault traces geolatts Point Bedding attitudes, etc. geolcald line Caldera boundaries geollins line Interpreted lineaments geolmeta line Metamorphic gradients The above coverages are attributed with numeric values and interpreted information. The entity files documented below show the data associated with each coverage.

Nevada

Gravity survey of the Tularosa Valley and adjacent areas, New Mexico

The gravity survey of the Tularosa Valley and adjacent areas is a compilation of gravity data acquired from several sources and reduced to the 1971 International Gravity Standardization Network datum. In addition, three local surveys were made that helped to fill in gaps in the gravity coverage. The resulting complete Bouguer gravity anomaly map and first- and third-order polynomial maps exhibit anomalies of great lateral extent and amplitudes that exceed 45 mGals. Five generalized geologic cross sections were constructed and analyzed by the two-dimensional method to investigate the thickness of the valley fill in Tularosa Valley and Jornada Del Muerto. On the basis of an assumed density contrast of 0.4 Mg/m3 between the valley fill. and the bedrock (pre-Cenozoic and Cenozoic rocks, undivided), the calculated depths to the pre-Cenozoic surfaces range from 1,372 to 2,743 m (4,500-9,000 ft).

Open-File Report

An analysis of gravity data in Area 12, Nevada Test Site

The gravity data available from Healey and Miller (1963a) were augmented by new observations along three profiles through two new drill holes in Area 12; UEI2t #1 and UEI2p #1. The data were interpreted to allow evaluation of the geologic structure prior to the planning and excavation of two proposed tunnel complexes, Ul2t and Ul2p. Density values for each of six rock units were determined to allow a two-dimensional analysis of the gravity data along the above-mentioned profiles. The surficial rocks of Quaternary and Tertiary age and the Tertiary volcanic rocks have a weighted average density of 1.86 gm/cc. The density of the caprock at Rainier and Aqueduct Mesas ranges from 2.17 gm/cc at UEI2p #1 to 2.27 gm/cc at UEI2t #1. The Gold Meadows stock and the associated Precambrian quartzite have an arithmetic average density of 2.60 gm/cc for all samples measured. The middle Paleozoic dolomite in Area 12 has an arithmetic average density of 2.75 gm/cc. The clastic rocks of Paleozoic age have an arithmetic average density of 2.60 gm/cc. Interpretation of the residual gravity data indicates a maximum thickness of about 2,800 feet for all Tertiary volcanic rocks. A normal fault striking N. 30 ? E. disrupts the pre-Cenozoic surface at UEI2p #1 and 0.4 mile east of UEI2t #1. The throw within rock of Paleozoic age is about 400-500 feet. Another normal fault that strikes about N. 20 ? E. is located about 1.5 miles east of UEI2p #1. The throw of this fault is at least 1,100 feet in rocks of pre-Cenozoic age. Elevation contours representing the pre-Cenozoic surface in Area 12 show a maximum relief of about 2,000 feet.

Nevada