Tectonics of the Qinling (Central China): tectonostratigraphy, geochronology, and deformation history
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- 作者：Ratschbacher ; Lothar ; Hacker ; Bradley R. ; Calvert ; Andrew ; Webb ; Laura E. ; Grimmer ; Jens C. ; et. al.
- 关键词：Structural geology ; Ar/Ar thermochronology ; Proterozoic to Cenozoic tectonics ; Ultrahigh-pressure orogeny ; Qinling ; Dabie Shan
- 刊名：Tectonophysics
- 出版年：2003
- 出版时间：May 1, 2003
- 年：2003
- 卷：366
- 期：1-2
- 页码：1-53
- 全文大小：7.34 M
文摘
The Qinling orogen preserves a record of late mid-Proterozoic to Cenozoic tectonism in central China. High-pressure metamorphism and ophiolite emplacement (Songshugou ophiolite) assembled the Yangtze craton, including the lower Qinling unit, into Rodinia during the ![]()
ter border=0 SRC=/images/glyphs/BQ1.GIF>1.0 Ga Grenvillian orogeny. The lower Qinling unit then rifted from the Yangtze craton at ![]()
ter border=0 SRC=/images/glyphs/BQ1.GIF>0.7 Ga. Subsequent intra-oceanic arc formation at ![]()
ter border=0 SRC=/images/glyphs/BQ1.GIF>470–490 Ma was followed by accretion of the lower Qinling unit first to the intra-oceanic arc and then to the Sino-Korea craton. Subduction then imprinted a ![]()
ter border=0 SRC=/images/glyphs/BQ1.GIF>400 Ma Andean-type magmatic arc onto all units north of the northern Liuling unit. Oblique subduction created Silurian–Devonian WNW-trending, sinistral transpressive wrench zones (e.g., Lo-Nan, Shang-Dan), and Late Permian–Early Triassic subduction reactivated them in dextral transpression (Lo-Nan, Shang-Xiang, Shang-Dan) and subducted the northern edge of the Yangtze craton. Exhumation of the cratonal edge formed the Wudang metamorphic core complex during dominantly pure shear crustal extension at ![]()
ter border=0 SRC=/images/glyphs/BQ1.GIF>230–235 Ma. Post-collisional south-directed shortening continued through the Early Jurassic. Cretaceous reactivation of the Qinling orogen started with NW–SE sinistral transtension, coeval with large-scale Early Cretaceous crustal extension and sinistral transtension in the northern Dabie Shan; it presumably resulted from the combined effects of the Siberia–Mongolia—Sino-Korean and Lhasa–West Burma—Qiangtang–Indochina collisions and Pacific subduction. Regional dextral wrenching was active within a NE–SW extensional regime between ![]()
ter border=0 SRC=/images/glyphs/BQ1.GIF>60 and 100 Ma. An Early Cretaceous Andean-type continental magmatic arc, with widespread Early Cretaceous magmatism and back-arc extension, was overprinted by shortening related to the collision of Yangtze–Indochina Block with the West Philippines Block. Strike–slip and normal faults associated with Eocene half-graben basins record Paleogene NNE–SSW contraction and WNW–ESE extension. The Neogene(?) is characterized by normal faults and NNE-trending sub-horizontal extension. Pleistocene(?)–Quaternary NW–SE extension and NE–SW contraction comprises sinistral strike–slip faults and is part of the NW–SE extension imposed across eastern Asia by the India–Asia collision.