气候变化领域集成服务门户(CCPortal): Rotation, narrowing, and preferential reactivation of brittle structures during oblique rifting

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DOI	10.1016/j.epsl.2019.115952
	Rotation, narrowing, and preferential reactivation of brittle structures during oblique rifting
	Duclaux G.; Huismans R.S.; May D.A.
发表日期	2020
ISSN	0012821X
卷号	531
英文摘要	Occurrence of multiple faults populations with contrasting orientations in oblique continental rifts and passive margins has long sparked debate about relative timing of deformation events and tectonic interpretations. Here, we use high-resolution three-dimensional thermo-mechanical numerical modeling to characterize the evolution of the structural style associated with varying geometries of oblique rifting in a layered continental lithosphere. Automatic analysis of the distribution of active extensional shear zones at the surface of the model demonstrates a characteristic sequence of deformation. Phase 1 with initial localization of deformation and development of wide moderately oblique en-échelon grabens limited by extensional shear zones oriented close to orthogonal to σ3 trend. Subsequent widening of the grabens is accompanied by progressive rotation of the phase 1 extensional shear zones to an orientation sub-orthogonal to the plate motion direction. Phase 2 is characterized by narrowing of active deformation resulting from thinning of the continental mantle lithosphere and development of a second-generation of extensional shear zones. During phase 2 deformation localizes both on plate motion direction-orthogonal structures that reactivate rotated phase 1 shear zones, and on new moderately oblique structures parallel to σ2. Finally, phase 3 consists in the oblique rupture of the continental lithosphere and produces an oceanic domain where oblique ridge segments are linked with highly oblique accommodation zones. We conclude that while new structures form and trend parallel to σ2 in an oblique rift, progressive rotation and long-term slip along phase 1 structures promotes orthorhombic fault systems, which accommodate upper crustal extension and control oblique passive margin architecture. The distribution, orientation, and evolution of frictional-plastic structures observed in our models consistent with documented fault populations in the Main Ethiopian Rift and the Gulf of Aden conjugate passive margins, both of which developed in moderately oblique extensional settings. © 2019 The Author(s)
关键词	normal faults numerical modeling rift systems tectonics transtension
英文关键词	Deformation; Faulting; Geologic models; Lithology; Numerical models; Plates (structural components); Rotation; Tectonics; Characteristic sequence; Continental lithosphere; Localization of deformation; Main Ethiopian Rift; Normal faults; Orthogonal structures; Rift systems; Transtension; Structural geology; brittle medium; deformation; graben; normal fault; numerical model; reactivation; rifting; rotation; shear zone; tectonics; thermomechanics; transtension; Arabian Sea; East African Rift; Ethiopian Rift; Gulf of Aden; Indian Ocean
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202570
作者单位	Department of Earth Science, University of Bergen, Allégaten 41, Bergen, 5007, Norway; Université Côte d'Azur, OCA, CNRS, IRD, Géoazur, 250 rue Albert Einstein, Valbonne, 06560, France; Department of Earth Sciences, University of Oxford, South Parks Road, Oxford, OX1 3AN, United Kingdom
推荐引用方式 GB/T 7714	Duclaux G.,Huismans R.S.,May D.A.. Rotation, narrowing, and preferential reactivation of brittle structures during oblique rifting[J],2020,531.
APA	Duclaux G.,Huismans R.S.,&May D.A..(2020).Rotation, narrowing, and preferential reactivation of brittle structures during oblique rifting.Earth and Planetary Science Letters,531.
MLA	Duclaux G.,et al."Rotation, narrowing, and preferential reactivation of brittle structures during oblique rifting".Earth and Planetary Science Letters 531(2020).