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Document Type |
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Article In Journal |
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Document Title |
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A Comparative Study of Five Volcanic-Hosted Sulfide Mineralizations in the Arabian Shield دراسة مقارنة لخمسة مواقع تمعدن كبريتيدية في الصخور البركانية بالدرع العربي |
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Subject |
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Earth Sciences |
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Document Language |
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English |
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Abstract |
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Investigation of five volcanogenic base metal sulfide occurrences
in the Arabian Shield (Ash Shizm, Umm Ad Damar, As-Safra, AI
Musayna'ah, and Umm Ash Shalahib) showed that they are located within
Hulayfah calc-alkaline volcan ic rocks or its equivalents. The investigations
included field , petrographic, mineralogical and chemical studies.
Felsic , calc-alkaline rock assemblages host these occurrences, with a predominance
of rhyolitic rocks and some andesites. Basalt occurs only in the
vicinity of the Ash Shizm mineralization . These rocks were regionally
metamorphosed to low greenschist facies grade. Deformation and contact
metasomatism affected parts of these occurrences producing foliation and
local skarn development. The intensity of metamorphism and deformation
varies between localities. Later episodes of hydrothermal activity overprinted
zones of mineralizations producing sericitization, chloritization and
silicification.
Geotectonieally, these mineral occurrences were formed in different settings
. Ash Shizm bimodal volcanics were probably deposited in an extensional
regime in a back arc basin. Umm Ad-Damar, As Safra and AI
Musayna'ah calc-alkaline volcanics are interpreted as formed within an island
arc environment, while Umm Ash Shalahib volcanics could be considered
similar to Andean type deposits related to an active continental margin
environment. Ore microscopic investigations of the mineral assemblages
in the five occurrences indicated primary orcs that have been
coarsened and deformed to variable degrees giving the ores their characteristic
brecciated nature reflected in the associated pyrite and other
metamorphic texture present.
Despite the extensive exploration programs carried out in the five areas
by DGMR, no economically worthwhile deposit has been recommended
for exploitation . The quantity and/or grade of these deposits, besides their occurrence in remote ~re~s without the infrastructure to support miningoper~
tions, c1~ssifies these deposits as non-economic in the ncar future.
For further exploration for volcanogenic sulfide deposits, the upper parts
of the Hul~yfah Group rocks or its equivalents arc recommended. Thc.
greatest pcrccntagc of known volc~nogenicmincr'll occurrences of the Ara.
hian Shield are located within their felsic volcanic and volc~niclasticrocks. |
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ISSN |
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1012-8832 |
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Journal Name |
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Earth Sciences Journal |
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Volume |
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6 |
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Issue Number |
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1 |
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Publishing Year |
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1413 AH
1993 AD |
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Number Of Pages |
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32 |
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Article Type |
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Article |
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Added Date |
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Sunday, October 11, 2009 |
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Researchers
| أحمد محمود الشنطي | A. M. AL-SHANTI | Researcher | | |
| عمر المهدي | O. R. EL-MAHDY | Researcher | | |
| ممدوح عبد الغفور حسن | M. A. HASSAN | Researcher | | |
| عبدالعزيز حسين | A. A. HUSSEIN | Researcher | | |
|