Late Cenozoic to Holocene deformation in southwestern Sichuan and adjacent Yunnan, China, and its role in formation of the southeastern part of the Tibetan Plateau

Research Article| March 01, 2000 Late Cenozoic to Holocene deformation in southwestern Sichuan and adjacent Yunnan, China, and its role in formation of the southeastern part of the Tibetan Plateau Erchie Wang; Erchie Wang 1Institute of Geology, Chinese Academy of Sciences, P.O. Box 9825, Beijing, China Search for other works by this author on: GSW Google Scholar B. Clark Burchfiel B. Clark Burchfiel 2Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 Search for other works by this author on: GSW Google Scholar GSA Bulletin (2000) 112 (3): 413–423. https://doi.org/10.1130/0016-7606(2000)1122.0.CO;2 Article history received: 23 Aug 1999 accepted: 20 Dec 1999 first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Erchie Wang, B. Clark Burchfiel; Late Cenozoic to Holocene deformation in southwestern Sichuan and adjacent Yunnan, China, and its role in formation of the southeastern part of the Tibetan Plateau. GSA Bulletin 2000;; 112 (3): 413–423. doi: https://doi.org/10.1130/0016-7606(2000)1122.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract From at least 2–4 Ma to present, crust in the southeastern part of the Tibetan Plateau west of the convex-east Xianshuihe-Xiaojiang fault system has deformed internally and rotated clockwise around the eastern Himalayan syntaxis. The northwest-striking Ganzi fault zone bounds the rotating crust on the north and has a total left slip of 78–100 km, of which ∼60 km is transferred to the Xianshuihe fault zone across a diffuse transfer zone, and ∼22–40 km is absorbed by bending of older structures and crustal shortening. Crustal shortening is expressed along and east of the eastern end of the Ganzi fault zone by mountains capped by permanent glaciers locally rising nearly 1000 m above the average elevation of the Tibetan Plateau. A similar transfer of left slip into shortening occurs farther south across the Xianshuihe fault in the high mountains around and east of Gongga Shan (7556 m). The northwest-striking, convex-east, left-lateral Litang fault zone lies southwest of the Ganzi-Xianshuihe-Xiaojiang fault zone and appears to be less well developed but otherwise similar to the Ganzi fault zone.The Batang, Chenzhi, and other northeast-striking right-lateral faults of small displacement occur within the rotating crustal fragment. Together with the left-slip faults, they accommodate east-west shortening northeast of the eastern Himalayan syntaxis. South of this region of shortening, the crust is extending to form grabens within the Dali and southern Xiaojiang fault systems and in the Tengchong volcanic province. The progressive change from shortening southward into extension is related to variations in strain that characterize the region from northeast to southeast of the eastern Himalayan syntaxis.The assemblage of structures in southwestern Sichuan geometrically resembles structures of Eocene to Miocene age in southern Yunnan that were positioned northeast of the eastern Himalayan syntaxis, similar to present-day southwestern Sichuan, at the time of their development. The similarity in the structural development in the two areas indicates that crust northeast of the syntaxis underwent a common evolution as the syntaxis migrated northward during the past ∼50 m.y. Structures in Sichuan are less fully developed than older structures in southwestern Yunnan and can serve as a guide to reconstruct the progressive tectonic development in the region of the syntaxis. Deformation in these areas indicates that plateau formation has been complex, inhomogeneous, and diachronous at scales from 1000 km to less than 100 km. You do not currently have access to this article.