In this paper,the Gaoyou-Baoying M_S4.9 earthquake was analyzed by the geomagnetic harmonic wave amplitude ratios method. The earthquake was an isolated seismic event,before and after which there were no other earthqu...In this paper,the Gaoyou-Baoying M_S4.9 earthquake was analyzed by the geomagnetic harmonic wave amplitude ratios method. The earthquake was an isolated seismic event,before and after which there were no other earthquakes occurred in this region. The dense distribution of geomagnetic observataries provided an advantage condition for the analysis of characteristics of the geomagnetic harmonic amplitude ratios. The analysis results verify the former knowledge of anomaly characteristics of the geomagnetic harmonic amplitude ratio,that is,the anomalous characteristics of the earthquake mostly appeared during the decline-turning-recovery rising process. The results also show that the change of the anomalies was asynchronous at the observatories close to the epicenter, namely, the anomalous characteristics were different between the H and the D components,as well as between the long and short periods.展开更多
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
基金funded by the routine task entitled“The Routine Recognition and Tracking of HVDC's Interference in Geomagnetic Observation”of the Technical Management Group of Electromagnetic Discipline,CEA
文摘In this paper,the Gaoyou-Baoying M_S4.9 earthquake was analyzed by the geomagnetic harmonic wave amplitude ratios method. The earthquake was an isolated seismic event,before and after which there were no other earthquakes occurred in this region. The dense distribution of geomagnetic observataries provided an advantage condition for the analysis of characteristics of the geomagnetic harmonic amplitude ratios. The analysis results verify the former knowledge of anomaly characteristics of the geomagnetic harmonic amplitude ratio,that is,the anomalous characteristics of the earthquake mostly appeared during the decline-turning-recovery rising process. The results also show that the change of the anomalies was asynchronous at the observatories close to the epicenter, namely, the anomalous characteristics were different between the H and the D components,as well as between the long and short periods.
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.
