气候变化领域集成服务门户(CCPortal): Feldspar microboudinage paleopiezometer and its applications to estimating differential stress magnitudes in the continental middle crust (examples from west Yunnan, China)

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DOI	10.1016/j.tecto.2021.228778
	Feldspar microboudinage paleopiezometer and its applications to estimating differential stress magnitudes in the continental middle crust (examples from west Yunnan, China)
	Ji S.; Li L.
发表日期	2021
ISSN	00401951
卷号	805
英文摘要	Feldspar, which is the most abundant crustal mineral, exhibits brittle behavior while quartz and mica deform plastically by dislocation creep, under the greenschist-facies conditions (300–450 °C). Pull-apart microboudinage, which formed by repeated cycles of tensile fractures, is a common microstructure observed in feldspar porphyroclasts embedded in the ductile matrix of quartz in granitic mylonites from the Red River, Chongshan and Gaoligong shear zones (Yunnan, China). These crustal-scale shear zones, which lie in the southeastern margin of the Tibet Plateau, have played a critical role in the southeastward lateral extrusion of the Indochina composite block in response to the Indo-Asian continental collision. Here we developed a feldspar microboudinage paleopiezometer. In each feldspar porphyroclast, the differential stresses estimated from microboudins progressively increases with sequential fracturing, depicting an evolution during exhumation of the mylonite upwards the brittle-ductile transition. The results from the feldspar microboudinage piezometer and the quartz recrystallized grain-size piezometer are largely consistent within the range of uncertainties. The microboudinage piezometer, combined with results of finite strain measurements, deformation temperature estimates, and thermochronological data, can yield the valuable information about rheological properties of naturally deformed rocks. It can also be directly used or adapted to a wide range of geological problems, for example, fractured pebbles in an unlithified matrix, chromite pods in serpentinized mantle rocks, and strong boudins in a soft material at any scale. © 2021 Elsevier B.V.
关键词	Boudinage Crustal rheology Feldspar Piezometer Southeastern Tibet Plateau Yunnan
英文关键词	Chromite; Fracture; Mica; Quartz; Structural geology; Tensile strength; Brittle ductile transitions; Continental collisions; Crustal-scale shear zones; Deformation temperatures; Differential stress; Dislocation creep; Recrystallized grain sizes; Rheological property; Feldspar; boudinage; continental collision; continental crust; exhumation; feldspar; piezometer; rheology; shear zone; stress; China; Qinghai-Xizang Plateau; Yunnan
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207995
作者单位	Département des Génies Civil, Géologique et des Mines, École Polytechnique de Montréal, Montréal, Québec H3C 3A7, Canada
推荐引用方式 GB/T 7714	Ji S.,Li L.. Feldspar microboudinage paleopiezometer and its applications to estimating differential stress magnitudes in the continental middle crust (examples from west Yunnan, China)[J],2021,805.
APA	Ji S.,&Li L..(2021).Feldspar microboudinage paleopiezometer and its applications to estimating differential stress magnitudes in the continental middle crust (examples from west Yunnan, China).Tectonophysics,805.
MLA	Ji S.,et al."Feldspar microboudinage paleopiezometer and its applications to estimating differential stress magnitudes in the continental middle crust (examples from west Yunnan, China)".Tectonophysics 805(2021).