[1]LIU Zifeng,FU Hong,PENG Guanling,et al.Temporal and Spatial Evolutionary Characteristics of Focal Mechanism Consistency before and after Three Strong Earthquakes in Yunnan in 2014[J].Journal of Seismological Research,2020,43(02):348-354.
Copy
Temporal and Spatial Evolutionary Characteristics of Focal Mechanism Consistency before and after Three Strong Earthquakes in Yunnan in 2014
Journal of Seismological Research[ISSN 1000-0666/CN 53-1062/P] Volume:
43
Number of periods:
2020 02
Page number:
348-354
Column:
Public date:
2020-06-10
- Title:
- Temporal and Spatial Evolutionary Characteristics of Focal Mechanism Consistency before and after Three Strong Earthquakes in Yunnan in 2014
- Keywords:
- strong earthquakes; focal mechanism consistency; variance of stress tensor; evolution in time and space
- CLC:
- P315.72
- DOI:
- -
- Abstract:
- Using the focal mechanism data of 3 121 earthquakes ML≥2.5 in Yunnan from 2008 to 2019,the spatial variation of the variance of the stress tensor and the temporal variation of the three strong earthquakes in 2014 were inversed by using the method of superposition stress field inversion,the temporal and spatial evolution characteristics of focal mechanism parameters before and after strong earthquakes were further analyzed.The results show that the epicenters of the three strong earthquakes are located in the region or the edge of the low variance of the stress tensor,and there are obvious regional differences in the spatial evolution before the earthquakes in each seismic region.The variance of stress tensor rises rapidly after earthquake,at the same time,two regions with low variance of stress tensor are formed in Western and south-southwest Yunnan.Change process about variance of stress tensor in the focal region generally showed a positive “V” shape in the three to five years before the three strong earthquakes,the descending process lasted for about two years and then began to turn and trend to rise again,the earthquake occurred in the rising phase of the “V” shape forming process,and the time interval between the rising and the occurrence of an earthquake is 1 to 3 years.The preliminary analysis shows that the focal mechanism of the source region before the three strong earthquakes tends to be the same,which is a manifestation of the stress enhancement in the seismogenic process.The turning point of the stress tensor variance after the decreases with time indicates that the urgency of strong earthquake is increased.
- References:
- -
- Similar References:
Memo
-
Last Update:
2020-06-10