Abstract
AbstractThe 12 May 2008 Wenchuan MS8.0 (Mw7.9) earthquake occurred on the Longmen Shan (Mountains) thrust‐nappe structure zone in the eastern margin of the Tibetan plateau. It has produced 240 km long and 72 km long rupture zones on the surface along the Yingxiu–Beichuan fault and Guanxian–Jiangyou fault, respectively, which are branches of the Longmen Shan fault system. Besides, our field investigation found that this shock has also caused a weak rupture zone on the ground nearby the Shigu town, Shifang city that lies in the western Chengdu plain east to the epicenter. This rupture zone and the other two ruptures in the Longmen Shan mountainous area aforementioned constitute a northwest‐dipping imbricate structure. It is about 7.5 km long, trends in 30‐, and is manifested by a series of deformation phenomena such as damages of buildings, channel dislocations, ground folds, erupted sand and earth fissures on the surface. Observations in the exploratory trenches indicate that there is a fold uplift of 0.2 m in the youngest strata (including the surface) produced by the Wenchuan MS8.0 event, and a fold uplift of 0.4 m in the clay bottom in the trench, presumably resulted from a paleoearthquake of similar size to the Wenchuan shock in 2008. Seismic exploration of shallow subsurface demonstrates that in the place of seismic rupture zone in the Chengdu plain exist active faults of the late Pleistocene as well as active folds of the Quaternary.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
