The rupture dimensions of earthquake faults are important parameters for characterizing earthquake ruptures and ground motions. Two key parameters to be determined are the rupture depth and dip angle of earthquake fau...The rupture dimensions of earthquake faults are important parameters for characterizing earthquake ruptures and ground motions. Two key parameters to be determined are the rupture depth and dip angle of earthquake faults. Dislocation theory in an elastic half space indicates that if a seismic rupture directly runs up to the ground surface, there exist zero points of horizontal strain in the surface deformation, which correspond to the rupture depths, except for pure strike-slip faults. In this study, we use numerical simulations to investigate the possibility of inferring rupture depths from zero-strain points for cases of buried faults and heterogeneous media. The results show that the correspondence of zero-strain points to the rupture depths can be influenced by the heterogeneity of the underground media and the stress field. For buried faults, the correspondence relationship is approximately valid when the fault depth is <1 km. In addition, the range of earthquake fault dip angles can be estimated by horizontal displacements on the ground. We also study how to determine the rupture depths of faults from InSAR data after large earthquakes, and successfully apply the method to the 2008 Wenchuan earthquake. The method proposed here, which determines the parameters of fault geometry according to surface deformation, is simple and easy to perform. With independent of aftershocks, it can provide valuable constraints to kinematic inversions.展开更多
The silver （Ag） nanowire arrays with regular and uniform size were successfully fabricated inside the nanochannels of anodic aluminum oxide （AAO） template by a simple paired cell method. X-ray diffi＇action （XRD...The silver （Ag） nanowire arrays with regular and uniform size were successfully fabricated inside the nanochannels of anodic aluminum oxide （AAO） template by a simple paired cell method. X-ray diffi＇action （XRD） and scanning elec- tron microscopy （SEM） results indicate that the as-synthesized samples are composed of face-centered cubic structure, and the average diameter is about 60-70 nm. Transmission electron microscopy （TEM） and the corresponding fast Fourier transformation （FFT） results show that Ag nanowires have a preferred single-crystal structure. Ultravio- let-visible （UV-vis） spectrum of Ag nanowire arrays exhibits UV emission band at 383 nm which can be attributed to the transverse dipole resonance ofAg nanowire arrays. A good surface-enhanced Raman scattering （SERS） spectrum is observed by excitation with a 514.5 nm laser, and the intensity of the SERS peak is about 23 times higher than that of the normal Raman peak measured from an empty AAO template. The high enhancement factor suggests that this method can be used to fabricate SERS sensor with high efficiency.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 41074070, 41174035)the SinoProbe Program (Grant No. SinoProbe-08-01)
文摘The rupture dimensions of earthquake faults are important parameters for characterizing earthquake ruptures and ground motions. Two key parameters to be determined are the rupture depth and dip angle of earthquake faults. Dislocation theory in an elastic half space indicates that if a seismic rupture directly runs up to the ground surface, there exist zero points of horizontal strain in the surface deformation, which correspond to the rupture depths, except for pure strike-slip faults. In this study, we use numerical simulations to investigate the possibility of inferring rupture depths from zero-strain points for cases of buried faults and heterogeneous media. The results show that the correspondence of zero-strain points to the rupture depths can be influenced by the heterogeneity of the underground media and the stress field. For buried faults, the correspondence relationship is approximately valid when the fault depth is <1 km. In addition, the range of earthquake fault dip angles can be estimated by horizontal displacements on the ground. We also study how to determine the rupture depths of faults from InSAR data after large earthquakes, and successfully apply the method to the 2008 Wenchuan earthquake. The method proposed here, which determines the parameters of fault geometry according to surface deformation, is simple and easy to perform. With independent of aftershocks, it can provide valuable constraints to kinematic inversions.
基金supported by the High Level Talents Introduction Project of Xinjiang Uygur Autonomous Region(No.2013)
文摘The silver （Ag） nanowire arrays with regular and uniform size were successfully fabricated inside the nanochannels of anodic aluminum oxide （AAO） template by a simple paired cell method. X-ray diffi＇action （XRD） and scanning elec- tron microscopy （SEM） results indicate that the as-synthesized samples are composed of face-centered cubic structure, and the average diameter is about 60-70 nm. Transmission electron microscopy （TEM） and the corresponding fast Fourier transformation （FFT） results show that Ag nanowires have a preferred single-crystal structure. Ultravio- let-visible （UV-vis） spectrum of Ag nanowire arrays exhibits UV emission band at 383 nm which can be attributed to the transverse dipole resonance ofAg nanowire arrays. A good surface-enhanced Raman scattering （SERS） spectrum is observed by excitation with a 514.5 nm laser, and the intensity of the SERS peak is about 23 times higher than that of the normal Raman peak measured from an empty AAO template. The high enhancement factor suggests that this method can be used to fabricate SERS sensor with high efficiency.
