气候变化领域集成服务门户(CCPortal): Structural architecture and Late Cretaceous exhumation history of the Saih Hatat Dome (Oman), a review based on existing data and semi-restorable cross-sections

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DOI	10.1016/j.earscirev.2021.103595
	Structural architecture and Late Cretaceous exhumation history of the Saih Hatat Dome (Oman), a review based on existing data and semi-restorable cross-sections
	Hansman R.J.; Ring U.; Scharf A.; Glodny J.; Wan B.
发表日期	2021
ISSN	0012-8381
卷号	217
英文摘要	The Saih Hatat Dome in the Al Hajar Mountains provides an outstanding opportunity to study subduction/exhumation processes coeval with obduction of the Semail Ophiolite. The exceptionally good outcrop conditions offer a unique opportunity to constrain the geometry of this subduction/obduction complex. In this review, the metamorphic, structural, and tectonic evolution of the Oman high-pressure complex in the Saih Hatat Dome is discussed. New structural cross-sections are developed and are used to interpret a geometrically feasible tectonic model for the Saih Hatat Dome. Our review highlights the importance of two major tectonic boundaries: (1) The As Sheik Shear Zone which separates the high pressure rocks of the As Sifah Unit (1.7–2.3 GPa and 510–550 °C) from the overlying Hulw Unit (1.0–1.2 GPa and 250–300 °C), and was active at ~79–76 Ma; and (2) the Upper Plate–Lower Plate Discontinuity, which forms a major surface in the landscape and developed by ~76–74 Ma, cutting through structures of the HP rocks in the lower plate (footwall). This discontinuity is associated with a pronounced strain gradient, notably in its upper plate (hanging wall), and separates rocks that have markedly different deformation geometry. The Upper Plate–Lower Plate Discontinuity initiated with a modest dip angle, making it a neutral structure in terms of crustal shortening vs extension. As a result, there is no discernable break in P-T conditions across it. The upper plate is dominated by the Saih Hatat Fold Nappe, forming between ~76 and 70 Ma. Subsequently, the upper plate has been dissected by a number of NNE-dipping thrusts at ~70–66 Ma, followed by normal faults at <~66 Ma. Our review and tectonic model indicate that the Oman high-pressure rocks were exhumed in a contractional tectonic setting that was possibly driven by forced return flow assisted by buoyancy forces. During this exhumation, when the rocks reached the greenschist-facies middle crust the Upper Plate–Lower Plate Discontinuity formed, as a shallow, south-dipping backthrust. Final exhumation of the high-P rocks was achieved by late normal faults after ~66 Ma. © 2021 The Authors
语种	英语
scopus关键词	architecture; Cretaceous; deformation; exhumation; obduction; ophiolite; P-T conditions; structural geology; subduction; tectonic evolution; tectonic setting; Oman; Oman Mountains; Saih Hatat
来源期刊	EARTH-SCIENCE REVIEWS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/209310
作者单位	State Key Laboratory of Lithospheric Evolution, Innovation Academy for Earth Science, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China; Department of Geological Sciences, Stockholm University, Stockholm, 106 91, Sweden; Department of Earth Sciences, College of Science, Sultan Qaboos University, Muscat; GFZ German Research Centre for Geosciences, Potsdam, 14473, Germany
推荐引用方式 GB/T 7714	Hansman R.J.,Ring U.,Scharf A.,et al. Structural architecture and Late Cretaceous exhumation history of the Saih Hatat Dome (Oman), a review based on existing data and semi-restorable cross-sections[J],2021,217.
APA	Hansman R.J.,Ring U.,Scharf A.,Glodny J.,&Wan B..(2021).Structural architecture and Late Cretaceous exhumation history of the Saih Hatat Dome (Oman), a review based on existing data and semi-restorable cross-sections.EARTH-SCIENCE REVIEWS,217.
MLA	Hansman R.J.,et al."Structural architecture and Late Cretaceous exhumation history of the Saih Hatat Dome (Oman), a review based on existing data and semi-restorable cross-sections".EARTH-SCIENCE REVIEWS 217(2021).