干旱区生态环境知识资源中心(Arid): Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits

Arid

DOI	10.1007/s12517-020-05982-8
	Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits
	Abd El Monsef, Mohamed; Slobodnik, Marek; Salem, Ibrahim A.
通讯作者	Abd El Monsef, M
来源期刊	ARABIAN JOURNAL OF GEOSCIENCES
ISSN	1866-7511
EISSN	1866-7538
出版年	2020
卷号	13 期号:19
英文摘要	The gold lode in Fatira area is represented in three modes of occurrence: (1) altered felsite dykes, (2) massive quartz veins that are cutting through the hosting granitic rocks, and (3) siliceous-hybrid shear zone which is trending in NNW-SSE direction and separating between metavolcanic and granitic rocks. Metavolcanic rocks are described by meta-andesite and meta-dolerite varieties; they exhibit calc-alkaline magma type related to island arc system. However, granitic rocks are of I-type granodiorite composition with calc-alkaline affinity developed in convergent plate environment (island arc/active continental margins) during the late stage of orogeny. The wallrock alteration around the ore body includes propylitization, sericitization, and silicification facies. The ore minerals were observed as disseminated sulfides (pyrite, sphalerite, chalcopyrite, and covellite). Goethite, jarosite, and ilmenite are the main iron-rich mineral phase as well as malachite and rutile. Gold was detected by microprobe analysis within the internal composition of pyrite and/or jarosite. Two groups of fluid inclusions could be recognized in samples from different mineralized zones: (a) aqueous fluid inclusions (H2O-NaCl/KCl) and (b) aqueous-carbonic fluid inclusions (H2O-CO2-NaCl/KCl). Isochore construction from fluid inclusion data, combined with chlorite thermometry from alteration zone, revealed that Fatira gold deposits were formed at temperature range of 275-297 degrees C and pressure between 0.2 and 1.1 kb). The Fatira gold deposits exhibit similar features of both intrusion-related and orogenic deposits. Hence, the initial ore-bearing fluid was proposed to have originated from magmatic source at deeper levels related to the granitic emplacement (5-10 kb); moreover, the granitic batholith acted as an important vehicle for driving of the metamorphic hydrothermal currents and probably as a cause for the metamorphic process itself. Then, the migration of gold was taken place in form of bi-sulfide complexes and the final deposition occurred through fluid uplifting consequent with a possibility of mixing with meteoric water at shallow depths, pressure/temperature drop, and fluid/wallrock interactions.
英文关键词	Geochemistry Microprobe Chlorite geothermometry Fluid inclusions Orogenic gold Granitic emplacement
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000576179900003
WOS关键词	PHASE-EQUILIBRIA ; CHEMICAL CLASSIFICATION ; GREENSTONE-BELT ; VOLCANIC-ROCKS ; AFRICAN OROGEN ; INCLUSION DATA ; MINERALIZATION ; EVOLUTION ; DISCRIMINATION ; OCCUPANCY
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/326675
作者单位	[Abd El Monsef, Mohamed; Salem, Ibrahim A.] Tanta Univ, Dept Geol, Fac Sci, Tanta 31527, Egypt; [Abd El Monsef, Mohamed; Slobodnik, Marek] Masaryk Univ, Inst Geol Sci, Fac Sci, Brno, Czech Republic
推荐引用方式 GB/T 7714	Abd El Monsef, Mohamed,Slobodnik, Marek,Salem, Ibrahim A.. Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits[J],2020,13(19).
APA	Abd El Monsef, Mohamed,Slobodnik, Marek,&Salem, Ibrahim A..(2020).Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits.ARABIAN JOURNAL OF GEOSCIENCES,13(19).
MLA	Abd El Monsef, Mohamed,et al."Characteristics and nature of gold-bearing fluids in Fatira area, North Eastern Desert of Egypt: possible transition from intrusion-related to orogenic deposits".ARABIAN JOURNAL OF GEOSCIENCES 13.19(2020).