The 2013 Lushan earthquake: Implications for seismic hazards posed by the Range Front blind thrust in the Sichuan Basin, China

Abstract

Research Article| October 01, 2014 The 2013 Lushan earthquake: Implications for seismic hazards posed by the Range Front blind thrust in the Sichuan Basin, China Maomao Wang; Maomao Wang 1Department of Earth Sciences, Nanjing University, Nanjing 210093, China2Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA3Department of Geophysics, Kyoto University, Kyoto 606-8502, Japan Search for other works by this author on: GSW Google Scholar Dong Jia; Dong Jia 1Department of Earth Sciences, Nanjing University, Nanjing 210093, China Search for other works by this author on: GSW Google Scholar John H. Shaw; John H. Shaw 2Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Search for other works by this author on: GSW Google Scholar Judith Hubbard; Judith Hubbard 2Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA4Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798 Search for other works by this author on: GSW Google Scholar Andreas Plesch; Andreas Plesch 2Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, USA Search for other works by this author on: GSW Google Scholar Yiquan Li; Yiquan Li 1Department of Earth Sciences, Nanjing University, Nanjing 210093, China Search for other works by this author on: GSW Google Scholar Baojin Liu Baojin Liu 5Geophysical Exploration Center, China Earthquake Administration, Zhengzhou 450002, China Search for other works by this author on: GSW Google Scholar Geology (2014) 42 (10): 915–918. https://doi.org/10.1130/G35809.1 Article history received: 25 Apr 2014 rev-recd: 05 Aug 2014 accepted: 07 Aug 2014 first online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Maomao Wang, Dong Jia, John H. Shaw, Judith Hubbard, Andreas Plesch, Yiquan Li, Baojin Liu; The 2013 Lushan earthquake: Implications for seismic hazards posed by the Range Front blind thrust in the Sichuan Basin, China. Geology 2014;; 42 (10): 915–918. doi: https://doi.org/10.1130/G35809.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Thrust and reverse faults pose significant earthquake hazards in convergent plate margins around the world, but have proven difficult to study given the complex nature of their ruptures, which often involve multiple along-strike and vertically stacked fault segments. The 2013 Mw 6.6 Lushan earthquake exemplified this complexity, rupturing a blind thrust fault in the southern Longmen Shan, which border the western Sichuan Basin in China. This event occurred 80 km south of the epicenter of the destructive 2008 Mw 7.9 Wenchuan earthquake. The Wenchuan earthquake produced surface ruptures on two parallel fault splays, the Pengguan and Beichuan faults. In contrast, the Lushan earthquake was generated by a ramp in the Range Front blind thrust (RFBT), which is in the footwall of the Wenchuan rupture. We use seismic reflection profiles, petroleum wells, and relocated seismicity to construct a three-dimensional model of this imbricated fault system. Our model illustrates that the 2013 Lushan earthquake ruptured <10% of the RFBT, which extends for 250 km along the Longmen Shan range front and into the western Sichuan Basin. Analysis of growth strata in structures above the RFBT fault along strike shows clear evidence of Quaternary activity and constrains the middle Pleistocene to current slip rate at two locations on the fault. Single segment and multisegment fault rupture scenarios involving the RFBT suggest the potential for large earthquakes (M7.8) that would affect the densely populated western Sichuan Basin. Assessing the hazards posed by such complex thrust systems, which occur in convergent margins worldwide, requires subsurface characterization of fault segments that can be independently associated with geologic and seismologic evidence of fault activity. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.