[1]YU Hailin,WAN Yongge,HUANG Shaohua,et al.Study on Focal Mechanism Solution and Stress Field of the 2021 Yangbi,Yunnan MS6.4 Earthquake Sequence Using P-wave First Motion Data[J].Journal of Seismological Research,2021,44(03):338-347.
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Study on Focal Mechanism Solution and Stress Field of the 2021 Yangbi,Yunnan MS6.4 Earthquake Sequence Using P-wave First Motion Data
Journal of Seismological Research[ISSN 1000-0666/CN 53-1062/P] Volume:
44
Number of periods:
2021 03
Page number:
338-347
Column:
Public date:
2021-10-20
- Title:
- Study on Focal Mechanism Solution and Stress Field of the 2021 Yangbi,Yunnan MS6.4 Earthquake Sequence Using P-wave First Motion Data
- Keywords:
- the Yangbi MS6.4 earthquake; P-wave initial motion; focal mechanism solution; stress field; maximum shear stress
- CLC:
- P315.727
- DOI:
- -
- Abstract:
- In order to reveal the seismogenic background of the Yangbi MS6.4 earthquake in Yunnan Province and its relationship with the surrounding stress field,the dataset of the seismic sequence from 14:28 on May 18 to 5:53 on June 8 is collected.The focal mechanism solutions of 85 earthquakes with MS≥2.5 before and after the MS6.4 main shock are calculated by using the method of P-wave initial motion.Then,according to the focal mechanism solution,the stress field in the source region is inverted by using the grid search method.Finally,the focal mechanism of the main shock and the stress field around it are simulated.The results show that the direction of the main compressive stress is near NS direction,and the extensional stress axis is near EW direction.This result is roughly the same as that of the stress field in the mainland of China.Through the simulation of the stress field and focal mechanism,it is found that the main shock basically occurred in the area with the nearly largest shear stress,and the difference between the direction of the shear stress and the slip direction of the mainshock was small,which indicated that by the action of the tectonic stress field,the mainshock occurred on the nodal plane with maximum shear stress releas.
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Last Update:
2021-10-20