Earthquake Fault Scarps and Cascading-Rupture Model for the Wenchuan Earthquake

• 责任者：Yu Guihua (Institute of Geology ; China Earthquake Administration ; Beijing 100029 ; China) ; Xu Xiwei
• 刊名：Earth Science Frontiers
• 出版年：2010
• 卷期：17(5)
• 关键词：汶川地震2008 ; Wenchuan earthquake 2008 ; 破碎带 ; fragmented zones ; 龙门山断裂带 ; Longmenshan Fault Zone
• 页码：p.1-18
• 图表：9 illus., 60 refs.
• 分类号：0500
• issnNo：ISSN1005-2321
• isbnNo：CN11-3370/P

The 2008 Mw 7.9 Wenchuan earthquake had caused the rupture of two NE-striking imbricated reverse faults and one NW-striking reverse fault along the Longmenshan range, which forms the eastern boundary of the Tibetan Plateau. On the basis of the morphology of the co-seismic fault scarp, the authors distinguish eight different categories of fault scarps, namely: the simple thrust scarp, the hanging-wall collapse scarp, the simple pressure ridge, the dextral pressure ridge, the fault-related fold scarp, the back-thrust pressure ridge, the local normal fault scarp and the pavement suprathrust scarp. The results of the aftershock focal mechanism show that the seismogenic fault dip angle is slowing down with depth, and is gradually steepening from southwest to northeast, which could be used to explain the increases of strike-slip component.