干旱区生态环境知识资源中心(Arid): Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, Egypt

Arid

	Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, Egypt
	Samuel Michael D; Moussa Hilmy E; Azer Mokhles K; Sadek Ghabrial Doris
来源期刊	Acta Geologica Sinica
ISSN	1000-9515
出版年	2019
卷号	93 期号:1 页码:50-73
英文摘要	The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominated by intermediate to silicic volcanics of medium-to high-K calc-alkaline affinity. It is divided into two units, the lower unit includes intermediate rocks and dacites interbedded with graywackes, semi-pelites and pelites and topped by polymict conglomerates. This unit is subjected to folding and regional metamorphism (up to garnet zone) and is intruded by quartz diorite-granodiorite inducing, locally, low-pressure contact thermal metamorphism. The unmetamorphosed upper unit encompasses acid volcanics intercalated with litharenite, sublitharenite and minor arenite. The rhyolites of this unit pertain to the highly fractionated granites and are characterized by an agpaitic index (NK/A) ranging from 0.87 to 0.96. They may reflect either extensive interaction of subduction-related magmas with the continental crust or a change in the tectonic regime. The present lithological and geochemical characteristics of the studied sediments together with available zircon ages indicate rather distal provenance of their detritus. This detritus comprises fluvial-alluvial sediments accumulated in the intermontane basins, which are half-grabens or tilted fault blocks. The tectonic setting of the depositional basins is active continental margin and continental island arcs. Geochemical patterns of the Zaghra volcano-sedimentary succession indicate their correlation with the Dokhan Volcanics-Hammamat Clastics sequence of the Eastern Desert of Egypt. Also, the Zaghra volcanics display geochemical similarities with those exposed in Sinai, at the Rutig, Ferani and Iqna Shar'a areas. The Zaghra succession is dated as Ediacaran but is not related either to the ensimatic island arc assemblage or to the rift-related assemblage formed during the early stages of the break-up of Rodinia as previously thought.
英文关键词	geochemistry Neoproterozoic Dokhan Volcanics Arabian-Nubian Shield Sinai Egypt
类型	Article
语种	英语
收录类别	CSCD
WOS研究方向	Geology
CSCD记录号	CSCD:6420018
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/336065
作者单位	Samuel Michael D, Geological Sciences Department, National Research Centre (NRC), Cairo, Egypt.; Moussa Hilmy E, Geological Sciences Department, National Research Centre (NRC), Cairo, Egypt.; Azer Mokhles K, Geological Sciences Department, National Research Centre (NRC), Cairo, Egypt.; Sadek Ghabrial Doris, Geological Sciences Department, National Research Centre (NRC), Cairo, Egypt.
推荐引用方式 GB/T 7714	Samuel Michael D,Moussa Hilmy E,Azer Mokhles K,et al. Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, Egypt[J],2019,93(1):50-73.
APA	Samuel Michael D,Moussa Hilmy E,Azer Mokhles K,&Sadek Ghabrial Doris.(2019).Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, Egypt.Acta Geologica Sinica,93(1),50-73.
MLA	Samuel Michael D,et al."Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, Egypt".Acta Geologica Sinica 93.1(2019):50-73.