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Robert L. Earhart

Publications and source records attributed to Robert L. Earhart.

21 records · Page 2Linked to original sources

Geologic reconnaissance of the Al Qunfidhah area, Tihamat Ash Sham quadrangle, Kingdom of Saudi Arabia

Preliminary mineral investigations in the A1 Qunfidhah area, Tihamat Ash Sham quadrangle, indicate that four target zones merit detailed study. These are (1) the West Gossan, (2) the pyrocalstic pile 13 Kilometers of Suq A1 Khamis, (3) the Wadi Sishah copper prospect, and (4) the Wadi Yiba copper prospect. Copper sulfides and carbonates appear to be the most abundant economic minerals present, although nickel, zinc, lead, molybdenum, gold, and silver may also occur in important amounts. In addition to locating specific target zones, the results delimit particular stratigraphic horizons which should be included in future regional mineral investigations. The rocks of the area are comprised of a eugeosynclinal assemblage of Precambrian metavolcanics and metasediments which are intruded by granitic rocks of at least two ages. Rocks which predate the latest granite intrusive are regionally metamorphosed, folded, and faulted. In most cases, zones containing economic minerals occur at or near the top of a volcanic pile and in marine sedimentary, rocks above the volcanic pile. The results from preliminary studies suggest a close genetic relationship between sulfide mineralization and volcanism.

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Report on exploration of the Wadi Yiba copper prospect, Tihamat Ash Sham quadrangle, Kingdom of Saudi Arabia

The first phase of an exploration program at The Wadi Yiba copper prospect consisted of geologic mapping, prospecting, sampling, geophysical surveys, and diamond drilling. Copper mineralization is in a sedimentary rock sequence comprised mostly of siliceous, calcareous, and dolomitic rocks metamorphosed to the greenschist facies. The metasedimentary rocks are overlain and underlain by metavolcanic rocks. They are folded into a tight north-plunging syncline transected by two fault systems. Results from the exploration program indicate that a fault zone which sub-parallels the synclinal axis and cuts siliceous dolomite contains copper mineralization and small amounts of gold and silver. Copper and silver beaming pyroclastic rocks were found in the upper part of the metasedimentary rock sequence. Concentrations of copper mineralization seem to be restricted to particular rock units in the metasedimentary rock sequence. Primary sulfides have not been encountered in the drill holes to date and the results from one drill hole indicate secondary copper sulfide minerals to a vertical depth of 60 meters. Further exploration seems to be warranted and a program is proposed which includes the investigation of other mineral occurrences and geophysical anomalies in the region.

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