干旱区生态环境知识资源中心(Arid): Hybrid granite magmatism during orogenic collapse in the Eastern Desert of Egypt: Inferences from whole-rock geochemistry and zircon U-Pb-Hf isotopes

Arid

DOI	10.1016/j.precamres.2020.106044
	Hybrid granite magmatism during orogenic collapse in the Eastern Desert of Egypt: Inferences from whole-rock geochemistry and zircon U-Pb-Hf isotopes
	Zoheir, Basem; Zeh, Armin; El-Bialy, Mohammed; Ragab, Azza; Deshesh, Fatma; Steele-MacInnis, Matthew
通讯作者	Zoheir, B (corresponding author), Bertha Univ, Fac Sci, Dept Geol, Banha 13518, Egypt.
来源期刊	PRECAMBRIAN RESEARCH
ISSN	0301-9268
EISSN	1872-7433
出版年	2021
卷号	354
英文摘要	Granites can provide detailed insights into crust formation and reworking during the different stages of orogenic cycles. New field and petrographic observations are integrated with whole-rock geochemical and zircon U-Pb and Hf isotopic data of granitic and subvolcanic felsite intrusions associated with the Atalla Shear Zone (ASZ). Formation of the ASZ is attributed to regional oblique convergence, late in the tectono-magmatic evolution of the Central Eastern Desert of Egypt. The new data reveal three stages of post-collisional felsic magmatism, with a change in magma type from I- to A-type granites. The evolution commenced with formation of quartzmonzodiorite and granodiorite at 639 +/- 2 Ma (stage 1), followed by a suite of granodiorite to syenogranite intrusions between 619 +/- 2 and 612 +/- 2 Ma (stage 2), and ceased with the Atalla felsites at 607 +/- 2 Ma (stage 3). During stages 1 and 2, the ASZ was intruded by hybrid granites as a result of mixing of lower crust material with mantle-derived mafic sanukitoid-like melts, in addition to nearly pure crustal melts during stage 2. The Atalla felsites, with distinct A-type affinities, are interpreted to have resulted from fractional crystallization of hybrid magmas in shallow crustal levels prior to emplacement. The identical initial Hf isotope compositions of all ASZ-associated magmatic rocks imply that the crust and mantle reservoirs had similar Hf isotopic composition at similar to 640-610 Ma (epsilon Hf(t) = 8 +/- 1). This implies that mantle enrichment was controlled largely by subducted Neoproterozoic oceanic crust, volcanic arc, and syn-collisional rocks. The new U-Pb ages combined with the geochemical characteristics of the ASZ granitic rocks are consistent with a prolonged period of decompression melting of hitherto enriched mantle and lower crust. Melting was likely triggered by rejuvenation of thoroughgoing transcurrent shearing and shear-driven asthenospheric mantle upwelling during the orogenic collapse stage.
英文关键词	Atalla shear zone Eastern Desert of Egypt Orogenic collapse Hybrid granites Geochemistry Zircon U-Pb-Hf isotopes
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000615712000007
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/2XILL650/351421
作者单位	[Zoheir, Basem] Bertha Univ, Fac Sci, Dept Geol, Banha 13518, Egypt; [Zoheir, Basem] Univ Kiel, Inst Geol Sci, Ludewig Meyn Str 10, D-24118 Kiel, Germany; [Zeh, Armin] Karlsruher Inst Technol KIT, Inst Angew Geowissensch Mineral & Petrol, Adenauerring 20b, D-76131 Karlsruhe, Germany; [El-Bialy, Mohammed] Port Said Univ, Fac Sci, Dept Geol, Port Said 42522, Egypt; [Ragab, Azza; Deshesh, Fatma] Mansoura Univ, Fac Sci, Dept Geol, Mansoura 35516, Egypt; [Steele-MacInnis, Matthew] Univ Alberta, Dept Earth & Atmospher Sci, Edmonton, AB T6G 2E3, Canada
推荐引用方式 GB/T 7714	Zoheir, Basem,Zeh, Armin,El-Bialy, Mohammed,et al. Hybrid granite magmatism during orogenic collapse in the Eastern Desert of Egypt: Inferences from whole-rock geochemistry and zircon U-Pb-Hf isotopes[J],2021,354.
APA	Zoheir, Basem,Zeh, Armin,El-Bialy, Mohammed,Ragab, Azza,Deshesh, Fatma,&Steele-MacInnis, Matthew.(2021).Hybrid granite magmatism during orogenic collapse in the Eastern Desert of Egypt: Inferences from whole-rock geochemistry and zircon U-Pb-Hf isotopes.PRECAMBRIAN RESEARCH,354.
MLA	Zoheir, Basem,et al."Hybrid granite magmatism during orogenic collapse in the Eastern Desert of Egypt: Inferences from whole-rock geochemistry and zircon U-Pb-Hf isotopes".PRECAMBRIAN RESEARCH 354(2021).