Spatio-temporal point pattern analysis on Wenchuan strong earthquake
Peijian Shi1, Jie Liu2, Zhen Yang3
1 Agricultural College, Jiangxi Agricultural University, Nanchang 330045, China 2 China Earthquake Networks Center, Beijing 100036, China 3 Department of Precision Instrument and Mechanology, Tsinghua University, Beijing 100084, China
Spatio-temporal point pattern analysis on Wenchuan strong earthquake
Peijian Shi1, Jie Liu2, Zhen Yang3
1 Agricultural College, Jiangxi Agricultural University, Nanchang 330045, China 2 China Earthquake Networks Center, Beijing 100036, China 3 Department of Precision Instrument and Mechanology, Tsinghua University, Beijing 100084, China
摘要For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aftershocks with magnitude M≥4.0, M≥4.5, and M≥5.0. It is found that these data exhibit the spatio-temporal clustering on a certain distance scale and on a certain time scale. In particular, the space-time interaction obviously strengthens when the distance is less than 60 km and the time is less than 260 h for the first two aftershock sequences; however, it becomes strong when the distance scale is less than 80 km and the time scale is less than 150 h for the last aftershock sequence. The completely spatial randomness analysis on the data regardless of time component shows that the spatial clustering of the aftershocks gradually strengthens on the condition that the distance is less than 60 km. The results are valuable for exploring the occurrence rules of the Wenchuan strong earthquake and for predicting the aftershocks.
Abstract：For exploring the aftershock occurrence process of the 2008 Wenchuan strong earthquake, the spatio-temporal point pattern analysis method is employed to study the sequences of aftershocks with magnitude M≥4.0, M≥4.5, and M≥5.0. It is found that these data exhibit the spatio-temporal clustering on a certain distance scale and on a certain time scale. In particular, the space-time interaction obviously strengthens when the distance is less than 60 km and the time is less than 260 h for the first two aftershock sequences; however, it becomes strong when the distance scale is less than 80 km and the time scale is less than 150 h for the last aftershock sequence. The completely spatial randomness analysis on the data regardless of time component shows that the spatial clustering of the aftershocks gradually strengthens on the condition that the distance is less than 60 km. The results are valuable for exploring the occurrence rules of the Wenchuan strong earthquake and for predicting the aftershocks.
