Surface deformation,along National Highway 213 at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan Province,China,is surveyed and measured in detail.The results show two distinct characteristics.One ...Surface deformation,along National Highway 213 at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan Province,China,is surveyed and measured in detail.The results show two distinct characteristics.One is that no horizontal displacement displays,or dextral strike-slip component at the observation point can not be found basically,the other is that uplift amount is 2.72 m,and the short-ening amount is 0.38 m,which reflects thrust shortening deformation is not obvious.The crust uplift amount of 2.71 m is distributed in a belt with width of 60 m.The model of lower crustal flow proposed by Royden et al.(1997) about the dynamic process in eastern margin of the Tibetan Plateau seems more suitable to explain the seismic surface deformation characteristics at Yingxiu Town,the epicenter of the May 12,2008 Wenchuan M8 Earthquake.展开更多
A statistical correlation method is used to study the effect of instability of the calculation datum （ used in traditional method of indirect adjustment） on calculated gravity results, using data recorded by Longmen...A statistical correlation method is used to study the effect of instability of the calculation datum （ used in traditional method of indirect adjustment） on calculated gravity results, using data recorded by Longmen Mountain regional gravity network during 1996 -2007. The result shows that when this effect is corrected, anomalous gravity changes before the 2008 Wenchuan Ms8. 0 earthquake become obvious and characteristically distinctive. Thus the datum-stability problem must be considered when processing and analyzing data recorded by a regional gravity network.展开更多
基金Supported by the Scientific Investigation Program of Wenchuan M8.0 Earthquake and Study on Seismic Safety of Nuclear Power Plant (Grant No.200708003)
文摘Surface deformation,along National Highway 213 at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan Province,China,is surveyed and measured in detail.The results show two distinct characteristics.One is that no horizontal displacement displays,or dextral strike-slip component at the observation point can not be found basically,the other is that uplift amount is 2.72 m,and the short-ening amount is 0.38 m,which reflects thrust shortening deformation is not obvious.The crust uplift amount of 2.71 m is distributed in a belt with width of 60 m.The model of lower crustal flow proposed by Royden et al.(1997) about the dynamic process in eastern margin of the Tibetan Plateau seems more suitable to explain the seismic surface deformation characteristics at Yingxiu Town,the epicenter of the May 12,2008 Wenchuan M8 Earthquake.
基金supported by the Eathquake Science Join Foundation( A07030)
文摘A statistical correlation method is used to study the effect of instability of the calculation datum （ used in traditional method of indirect adjustment） on calculated gravity results, using data recorded by Longmen Mountain regional gravity network during 1996 -2007. The result shows that when this effect is corrected, anomalous gravity changes before the 2008 Wenchuan Ms8. 0 earthquake become obvious and characteristically distinctive. Thus the datum-stability problem must be considered when processing and analyzing data recorded by a regional gravity network.
