On August 8,2017,an M_(W)6.5 earthquake occurred in Jiuzhaigou County,Sichuan Province,China,on the eastern margin of the Qinghai-Tibet Plateau.This study investigates the coseismic deformation field and fault model w...On August 8,2017,an M_(W)6.5 earthquake occurred in Jiuzhaigou County,Sichuan Province,China,on the eastern margin of the Qinghai-Tibet Plateau.This study investigates the coseismic deformation field and fault model with ascending and descending Sentinel-1 synthetic aperture radar(SAR)images,aftershock distribution,and elastic half-space dislocation model.The regional fault slip pattern is then quantita-tively examined using the boundary element method.The results show that the ascending and descending interferometric synthetic aperture radar(InSAR)coseismic deformation fields display an overall NNW-SSE trend,with more significant deformation on the southwest side of the fault.The coseismic fault geometry is divided into NW and SE sub-faults with strikes of 162.1°and 149.3°,respectively.The coseismic fault slip is dominated by a left-lateral strike-slip movement with an average rake of-2.31°,mainly occurring at a depth of 0-13.04 km with a shape of an approximately inverted triangle.The fault slip features two peak slip zones,with a maximum of 1.39 m.The total seismic moment is 6.34×10^(18) N·m(M_(W)6.47).The boundary element calculation quantitatively indicates that the regional fault slip pattern may be mainly attributable to the changing strike and dip.The strike changes from NNWeSSE to nearly NS direction,and the dip gradually decreases from the Jiuzhaigou earthquake fault in the north to the Huya fault in the south.With these characteristics,the Huya and the Jiuzhaigou earthquake faults form the eastern boundary of the Minshan uplift zone and accommodate the accumulated deformation.展开更多
The disaster area of the Pishan M_S6.5 earthquake in 2015 is located in the southern margin of the Tarim Basin,where the natural condition are harsh,and the economy is extremely backward.Moreover,because of a large nu...The disaster area of the Pishan M_S6.5 earthquake in 2015 is located in the southern margin of the Tarim Basin,where the natural condition are harsh,and the economy is extremely backward.Moreover,because of a large number of residential housing with poor seismic performance in the disaster area,the damage and economic losses are serious.Since the most disaster area is located in the piedmont overflow,with poor site conditions such as shallow groundwater level and soil foundation,the magnifying effect of ground motion has a significant impact on the damage.In conclusion,we believe that investment in antiearthquake housing projects should be increased in post disaster reconstruction.Furthermore,for the north of the disaster area,with the dense population,poor conditions like soft soil foundation and poor engineering geological conditions,we recommend that in the future construction of anti-earthquake housing projects,more attention should be paid to strengthen the foundation treatment and precaution measures.展开更多
基金This work was supported by the National Key Research and Development Program of China(2018YFC1503603,2016YFB0501405)the National Natural Science Foundation of China(41874011,41774011)。
文摘On August 8,2017,an M_(W)6.5 earthquake occurred in Jiuzhaigou County,Sichuan Province,China,on the eastern margin of the Qinghai-Tibet Plateau.This study investigates the coseismic deformation field and fault model with ascending and descending Sentinel-1 synthetic aperture radar(SAR)images,aftershock distribution,and elastic half-space dislocation model.The regional fault slip pattern is then quantita-tively examined using the boundary element method.The results show that the ascending and descending interferometric synthetic aperture radar(InSAR)coseismic deformation fields display an overall NNW-SSE trend,with more significant deformation on the southwest side of the fault.The coseismic fault geometry is divided into NW and SE sub-faults with strikes of 162.1°and 149.3°,respectively.The coseismic fault slip is dominated by a left-lateral strike-slip movement with an average rake of-2.31°,mainly occurring at a depth of 0-13.04 km with a shape of an approximately inverted triangle.The fault slip features two peak slip zones,with a maximum of 1.39 m.The total seismic moment is 6.34×10^(18) N·m(M_(W)6.47).The boundary element calculation quantitatively indicates that the regional fault slip pattern may be mainly attributable to the changing strike and dip.The strike changes from NNWeSSE to nearly NS direction,and the dip gradually decreases from the Jiuzhaigou earthquake fault in the north to the Huya fault in the south.With these characteristics,the Huya and the Jiuzhaigou earthquake faults form the eastern boundary of the Minshan uplift zone and accommodate the accumulated deformation.
基金funded by the “Three-in-one Project ” of China Earthquake Administration (163101)the Spark Program of Earthquake Sciences,CEA (XH15044Y)
文摘The disaster area of the Pishan M_S6.5 earthquake in 2015 is located in the southern margin of the Tarim Basin,where the natural condition are harsh,and the economy is extremely backward.Moreover,because of a large number of residential housing with poor seismic performance in the disaster area,the damage and economic losses are serious.Since the most disaster area is located in the piedmont overflow,with poor site conditions such as shallow groundwater level and soil foundation,the magnifying effect of ground motion has a significant impact on the damage.In conclusion,we believe that investment in antiearthquake housing projects should be increased in post disaster reconstruction.Furthermore,for the north of the disaster area,with the dense population,poor conditions like soft soil foundation and poor engineering geological conditions,we recommend that in the future construction of anti-earthquake housing projects,more attention should be paid to strengthen the foundation treatment and precaution measures.
