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G.I. Selner

Publications and source records attributed to G.I. Selner.

At least 37 records · Page 2Linked to original sources
USGS1987

About GSMAP and GSDRAW

The documentation for GSMAP and GSDRAW attempts a systematic description of these programs. This text is a supplement providing ideas developed during use of the programs and answering some of the common questions asked by new users at training sessions. The first sections of this text are written for new users who have scanned the documentation, but have not yet studied it. Later sections are written to provide ideas for old hands, explain some of the workings of the programs, and offer a few ideas on problem solving based on use of arcane aspects of the programs. The later sections assume familiarity with GSDRAW and/or GSMAP.

Open-File Report↗
USGS1985

Regional geochemical study of the felsic plutonic rocks in the Nuqrah Quadrangle, sheet 25E, Kingdom of Saudi Arabia

A regional geochemical investigation of the felsic plutonic rocks of the Nuqrah quadrangle, sheet 25 E, Kingdom of Saudi Arabia, in which pan concentrates of 384 wadi samples, and 145 rock samples, were collected, defined two separate and distinct anomalous areas. One area contains Jabal Tuwalah and Jabal Awja, and the other is at the north end of Jabal Safad. Both pan concentrates and the rock samples in the Jabal Tuwalah and Jabal Awja areas contain high concentrations of Be, F, La, Mo, Nb, Pb, Th, U, Sn, Y, and Zr, and the plutons underlying those areas are characterized by high total-count radioactivity. These elements are sited in highly evolved alkalic granites and have not been concentrated into a potentially metalliferous deposit related to a hydrothermal ore system. They may be a potential metal source of the future. Pan-concentration samples collected from wadis draining the north end of Jabal Safad contain anomalous Sn, Mo, Pb, and La. Four samples contain 250 to 1,000 ppm of tin. The tin anomaly is associated with a small aplitic pluton intrusive into the Jabal Safad alkalic granite complex. A brief reconnaissance of the area did not reveal any greisen or cassiterite mineralization. However, further exploration work in the area is recommended.

Open-File Report↗
USGS1985

Interpretation of geochemical data from panned concentrates of wadi sediments using R-mode factor analysis, Jabal Habashi Quadrangle, sheet 26F, Kingdom of Saudi Arabia

Panned-concentrate samples from wadi sediments were collected over terranes of Precambrian age intrusive, volcanic, sedimentary, and metamorphic rocks, within the Jabal Habashi quadrangle, sheet 26F, Kingdom of Saudi Arabia. Multivariate analysis of the chemical data indicates that a significant base-metal association occurs in three areas within the quadrangle. An association of strontium, barium, and calcium possibly indicates areas of hydrothermal alteration. Three other associations that were found define the major rock lithologies: niobium-yttrium-lanthanum outlines granitic terranes; magnesium-nickel indicates mafic rocks; and cobalt-vanadium-chromium have an indefinite relation with units mapped as graywacke in the central part of the quadrangle.

Open-File Report↗
USGS1985

Reconnaissance geochemical exploration of plutons of syenite and shonkinite, southern Asir, Kingdom of Saudi Arabia

Reconnaissance geochemical exploration for rare metals in plutons of syenite and shonkinite disclosed generally less than 20 ppm Nb in rocks, wadi sediments, and concentrates. The sparsity of Nb is accompanied by low values for La, Sn, W, Y, and Zr and relatively high but insignificant values for Be and Mo. Base and precious metals are either below their respective limits of determination in the various sample media or are present at background levels commensurate with average crustal abundances in felsic rocks. Pegmatite dikes associated with the syenite plutons are rare and lack vermiculite. The present investigation disclosed no possible ore deposits in the plutons covered by the field work. Known kyanite-topaz-natroalunite rocks in the vicinity of the surveyed areas should be examined for possible deposits of Cu, Mo, or Au associated with high-alumina hydrothermal deposits.

Open-File Report↗
USGS1985

Reconnaissance geochemical exploration of the plutons of quartz monzonite and granite in the Jabal Lababa and Ar Rayth areas, southern Asir, Kingdom of Saudi Arabia

Geochemical reconnaissance for rare metals in plutons of albite-muscovite granite and quartz monzonite in the vicinity of Jabal Lababa disclosed positive geochemical anomalies for beryllium, tantalum, thorium, lanthanum, niobium, tin, yttrium, and zirconium. The low anomalous values for the rare metals in rocks and the short mechanical dispersion trains, seldom exceeding 4 km in length, of rare-metal-bearing heavy minerals, are interpreted to indicate that primary deposits of these metals are lacking, and any placers would be small and low in tenor. Small positive anomalies for barium were detected at scattered localities in the metasediments adjacent to the plutons in the Jabal Lababa area. Positive anomalies for the precious metals are lacking, and the low values observed for base metals do not indicate the presence of sulfide deposits. The abundant quartz lag gravel in the eastern part of the area is unmineralized. Small books of muscovite are present in some pegmatite, but is of non-commercial volume and quality. A subcircular structure at the coast of the Red Sea near the mouth of Wadi Nahb should be tested to determine if it is a buried salt dome. Three nonmagnetic high-density concentrates containing 1,000 to 15,000 ppm lead were found on the granitic pluton near Ar Rayth. The source of the lead is not galena, and high values for lead appear to be characteristic of the pluton but do not indicate an ore deposit.

Open-File Report↗