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Vincent J. Flanigan

Publications and source records attributed to Vincent J. Flanigan.

22 records · Page 2Linked to original sources
USGS1975

Airborne gamma-radiation survey of the Jabel Ishmas Quadrangle, Kingdom of Saudi Arabia

An airborne gamma-radiation survey system, which includes digital recording and automatic data processing procedures developed by the U. S. Geological Survey Saudi Arabian Project, is used to collect spectral gamma-radiation data as an aid to regional geologic mapping of pediment areas on the Arabian Shield. The areal extent of rock units can generally be distinguished by the intensity of their radiation pattern. Rocks of ultramafic composition have low radiation response, whereas more felsic rocks reflect higher radiation response. Interpretations based on radiometric data enable the geologist to gain some understanding about the geologic setting of an area before he begins field mapping.

Open-File Report↗
USGS1975

Tungsten anomalies in the Uyaijah ring structure, Kushaymiyah igneous complex, Kingdom of Saudi Arabia - Section A, Geology and geochemistry of the Uyaijah ring structure; Section B, Regional geophysics

Anomalous amounts of tungsten, molybdenum, and bismuth are present in the Uyaijah ring structure of the Kushaymiyah igneous complex in the eastern part of the Precambrian shield of the Kingdom of Saudi Arabia. The complex includes four major rock units, the Murdama Group, porphyritic granodiorite, quartz monzonite, alkaline granite, and areas enriched in silica. Structural and compositional relationships among some of the rock units are defined in part by aeromagnetic and gamma-ray spectrometric geophysical data. Geochemical data from -10 +30 mesh surficial debris were primarily related to the composition of the major rock units, whereas data from heavy-mineral concentrates were used to establish the location of tungsten-molybdenum-bismuth anomalies. Two areas of about 40 sq km each are occupied by tungsten-molybdenum-bismuth anomalies interpreted to be related to the alkaline granite. One of these is a contact metasomatic anomaly; the other is related to leakage from an inferred underlying cupola of the alkaline granite. These two anomalous areas are recommended for further investigation

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