JpGU-AGU Joint Meeting 2017

Presentation information

[EE] Poster

S (Solid Earth Sciences) » S-SS Seismology

[S-SS07] [EE] Surface Ruptures During Earthquakes: Mapping, Analyses, and Hazard Assessment

Wed. May 24, 2017 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall HALL7)

convener:Koji Okumura(Graduate School of Letters, Hiroshima University), St?phane Baize(Institut de Radioprotection et de S?ret? Nucl?aire), Nobuhisa Matsuta(Okayama University Graduate School of Education), Takashi Azuma(National Institute of Advanced Industrial Science and Technology)

[SSS07-P02] Shallow crustal structures triggered by the ML6.6 Meinong earthquake, southwestern Taiwan, from field investigation of surface deformation and damages

*Ling-Ho Chung1, Ray Y Chuang2, J Bruce H Shyu3, Mong-Han Huang4, Kenn-Ming Yang5, Kuo-En Ching6, Yuan-Hsi Lee1 (1.Department of Earth and Environmental Sciences, National Chung Cheng University, 2.Department of Geography, National Taiwan University, 3.Department of Geosciences, National Taiwan University, Taipei, Taiwan, 4.Jet Propulsion Laboratory, California Institute of Technology, Pasadena, USA, 5.Department of Earth Sciences, National Cheng Kung University, 6.Department of Geomatics, National Cheng Kung University)

Keywords:Meinong earthquake, InSAR

The ML6.6 Meinong earthquake on 6 February 2016 caused serious damages in southwestern Taiwan. Coseismic displacement derived from GPS and InSAR shows ~10 cm dome-shaped surface uplift 15 km west of the epicenter with two clear N-S trending discontinuities in the InSAR fringes around the town of Guanmiao, which are highly related to building damages and surface cracks observed in the field. In this study, we integrate seismic reflection data, geologic data, and results from field investigation to construct shallow crustal structural geometry. The two lineaments near Guanmiao seen in the InSAR result may be induced by local shallow folding in the Liushuang - Erhchuangchi (LS-EC) Formation. Instead of being a traditional fault-bend fold, the significant uplift west of Guanmiao may be associated with pure shear deformation of clayey Gutingkeng (GTK) Formation. Our result suggests that lower crustal earthquakes can trigger active structures at shallower depths, which is capable of generating localized surface deformation and damages.