DOI: 10.1007/s00531-014-1094-6
Scopus记录号: 2-s2.0-84925461301
论文题名: Metal and fluid sources in a potential world-class gold deposit: El-Sid mine, Egypt
作者: Helmy H. ; Zoheir B.
刊名: International Journal of Earth Sciences
ISSN: 14373254
出版年: 2015
卷: 104, 期: 3 起始页码: 645
结束页码: 661
语种: 英语
英文关键词: Deposition mechanism
; Egypt
; El-Sid gold deposit
; Metal and fluid sources
英文摘要: Lode gold mineralization at the El-Sid mine area is associated with the ca. 600 Ma Fawakhir granite intrusion, which cuts the ~737 Ma ophiolite nappes in the Central Eastern Desert of Egypt. The mineralized quartz veins are hosted by ~E- and NE-trending fault/fracture sets cutting the western boundary of the intrusion and sheared ophiolites. The results of electron microprobe analyses of gold-associated hydrothermal sulfide and silicate minerals suggest that Au was mobilized alongside Ni, Co, Cr and As from the adjacent ophiolitic serpentinite. After granite emplacement, hydrothermal fluids interacted with the sheared serpentinite, leaching metals and re-depositing them in the faults/fractures and adjacent wall rock in a cyclic process. Low-salinity aqueous-carbonic fluids with significant quantities of volatile species (CO2, CH4, and N2 ± H2S) leached and transported Au from deep to shallow crustal levels. Carbon dioxide had a buffering effect on the Au-bearing hydrothermal solution, maintaining its pH within a narrow near-neutral range, where elevated gold concentration was transported by complexation with reduced magmatic sulfur in a reducing environment. Gold deposition along fault/fracture conduits in the Fawakhir granite and adjacent serpentinite resulted from interplay of pressure drop, fluctuations in oxygen and sulfur fugacities, and exsolution of the volatile phases. Infiltration of meteoric water may have contributed to the formation of the late stage gold-sulfide mineralization that formed at shallower levels during terrane uplift. Sulfidation of the Fe-rich magmatic minerals was, on the other hand, the overriding process in the wall rock as evidenced by abundant disseminated sulfides with gold inclusions. Considering the structural control by regional shear zones (fluid conduits) and the voluminous granitic and ophiolitic rocks (metal sources), a high tonnage gold deposit amenable to open pit mining at the El-Sid mine area is very likely. © 2014, Springer-Verlag Berlin Heidelberg. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84925461301&doi=10.1007%2fs00531-014-1094-6&partnerID=40&md5=4e7374360d739983ceba6bc61fc054c1
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/70303
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
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作者单位: Department of Geology, Minia University, Minia, Egypt; Department of Geology, Benha University, Benha, Egypt
Recommended Citation:
Helmy H.,Zoheir B.. Metal and fluid sources in a potential world-class gold deposit: El-Sid mine, Egypt[J]. International Journal of Earth Sciences,2015-01-01,104(3)