On July 20,2012,the Ms 4.9 Baoying Earthquake occurred near the junction of Baoying County and Gaoyou City in Jiangsu Province,eastern China.Due to no obvious surface rupture and limited observation of earthquake sequ...On July 20,2012,the Ms 4.9 Baoying Earthquake occurred near the junction of Baoying County and Gaoyou City in Jiangsu Province,eastern China.Due to no obvious surface rupture and limited observation of earthquake sequence,the seismogenic structure of the Ms 4.9 Baoying Earthquake is still unclear.In this study,80 earthquakes provided by China Earthquake Network Center(CENC)are first relocated;and then the relocated 75 events with high signal-to-noise ratios as templates are utilized to scan through continuous waveform data(July 11 to August 31,2012)using graphics processing unit-based match and locate(GPU-M&L)technique.Then the Deep Denoiser,a deeplearning-based noise reduction technique,is used to further confirm some newly detected events;and the double-difference relocation(Hypo DD)algorithm is used to relocate the earthquakes.We detect and relocate more than twice as many events as the CENC routine catalog,which includes 15 foreshocks and 230 aftershocks.The results show that the foreshocks are mainly distributed in the NW direction along the extended SE section of the blind Xiagonghe fault(XF),which is orthogonal to the strike of the seismogenic fault of the Ms 4.9 Baoying Earthquake(Yangchacang-Sangshutou fault,named YSF).Most of the aftershocks are generally distributed along the NNE-trending YSF and illuminate a steeply dipping plane.This study reveals detailed spatiotemporal evolution of the earthquake sequence and suggests that the buried XF extends southeastward and cuts through the NNE-trending seismogenic YSF.展开更多
The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the ...The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters.展开更多
基金supported by the National Natural Science Foundation of China(No.U1939203)the National Key R&D Program of China(No.2017YFC150040)Shanghai Sheshan National Geophysical Observatory(No.2020K02)。
文摘On July 20,2012,the Ms 4.9 Baoying Earthquake occurred near the junction of Baoying County and Gaoyou City in Jiangsu Province,eastern China.Due to no obvious surface rupture and limited observation of earthquake sequence,the seismogenic structure of the Ms 4.9 Baoying Earthquake is still unclear.In this study,80 earthquakes provided by China Earthquake Network Center(CENC)are first relocated;and then the relocated 75 events with high signal-to-noise ratios as templates are utilized to scan through continuous waveform data(July 11 to August 31,2012)using graphics processing unit-based match and locate(GPU-M&L)technique.Then the Deep Denoiser,a deeplearning-based noise reduction technique,is used to further confirm some newly detected events;and the double-difference relocation(Hypo DD)algorithm is used to relocate the earthquakes.We detect and relocate more than twice as many events as the CENC routine catalog,which includes 15 foreshocks and 230 aftershocks.The results show that the foreshocks are mainly distributed in the NW direction along the extended SE section of the blind Xiagonghe fault(XF),which is orthogonal to the strike of the seismogenic fault of the Ms 4.9 Baoying Earthquake(Yangchacang-Sangshutou fault,named YSF).Most of the aftershocks are generally distributed along the NNE-trending YSF and illuminate a steeply dipping plane.This study reveals detailed spatiotemporal evolution of the earthquake sequence and suggests that the buried XF extends southeastward and cuts through the NNE-trending seismogenic YSF.
基金National Natural Science Foundation of China (40074010) and Natural Science Foundation of Gansu Province(ZS981-A25-011).
文摘The 3-D velocity tomography image of the central-eastern part of Qilianshan is obtained by the joint inversion of 3-D velocity structure and focal parameters based on the S-P data of micro-earthquakes recorded by the digital seismic network set up for a Sino-French cooperation program since 1996. The inversed velocity structure does primarily reflect some important features of the deep structure in the region and provide the scientific background for the further study of active tectonic structure and the calculation of earthquake parameters.
