基于速率—状态摩擦准则的库仑应力转移模型的地震活动研究——以川滇地区为例
Seismicity Related to Coulomb Stress Transfer Model and Rate-state Friction Criterion:A Case Study in the Sichuan-Yunnan Region
王力维 1王辉 1曹建玲 1姚琪1
作者信息
- 1. 中国地震局地震预测研究所,北京 100036
- 折叠
摘要
川滇地区地处青藏高原东南缘,近年来强震活动频繁,该地区的强震活动研究一直备受关注.本文利用速率—状态摩擦准则和区域地震目录,计算并得到了川滇地区1976-2019年发生的8次MW≥6.5强震产生的库仑应力扰动所导致的MS≥5.0地震活动率空间分布.结果表明,2020-2023年间实际发生的MS≥5.0地震大多数发生在计算得到的地震活动率高值区.川滇地区的地震活动受到强震引起的应力扰动与不同区域孕震环境的共同影响.强震应力扰动场对后续地震活动的影响主要集中在震源区附近,而部分区域较高的地震活动率则与当地较高的背景地震活动有关.川滇地区MS≥5.0地震活动率较高的地区位于龙门山断裂南北端、丽江—小金河断裂、瑞丽—龙陵断裂、澜沧江断裂以及长宁地区等.本文研究结果为川滇地区中强地震的时空分布特征提供了新的认识,并为区域地震危险性评估提供了参考.
Abstract
The Sichuan-Yunnan region is located at the southeastern margin of the Qinghai-Xizang Plateau,where strong earthquakes have occurred frequently in recent years,draw-ing much attention to the study of strong earthquake activity trends in this area.This pa-per calculates the spatial distribution of M≥5.0 seismic activity rates caused by Coulomb stress perturbations resulting from 8 strong MW≥6.5 earthquakes that occurred in the Si-chuan-Yunnan region from 1976 to 2019,using the rate-state friction law and regional earthquake catalogs.The results indicate that the calculated seismic activity rates based on the rate-state friction criterion is generally consistent with the spatial distribution ofM≥5.0 earthquakes that occurred between 2020 and 2023.Earthquake activity in the Sichuan-Yunnan region is jointly influenced by stress perturbations caused by strong earthquakes and seismogenic environments in different regions.The impact of strong earthquake stress perturbation fields on subsequent seismic activity is mainly concentrated in areas near strong earthquakes;while the higher seismic activity rates in some regions are related to the higher background seismic activity in the region.The areas with higher M≥5.0 seis-mic activity rates in the Sichuan-Yunnan region are located at the northern and southern ends of the Longmenshan fault,the Lijiang-Xiaojinhe fault,the Ruili-Longling fault,the Lancang River fault,and the Changning area.The results of this study provide new in-sights into the spatial and temporal distribution characteristics of moderate to strong earth-quakes in the Sichuan-Yunnan region and serve as a reference for regional seismic hazard assessment.
关键词
川滇地区/库仑应力/速率—状态摩擦准则/背景地震活动Key words
Sichuan-Yunnan region/Coulomb stress/Rate-state friction law/Back-ground seismicity引用本文复制引用
出版年
2024
NETL
NSTL
万方数据