交城断裂带北段最大潜在地震发震概率评估1

基于太原市目标区交城断裂带的定量研究,特别是对活动断裂上的古地震资料进行的系统、详细的分析与总结,建立了反映该断裂地震地质特点和运动学属性的复发模式和概率模型.引入震级-地表破裂长度、震级-震源破裂长度、震级-断层破裂面积以及震级-地震矩的经验关系进行震级估计,最后进行综合评估以确定交城断裂带北段潜在地震的最大震级.复发模式的建立兼顾了泊松和准周期两种模式,利用专家意见法组合相应的Poisson模型和BPT模型,计算活动断裂最大潜在地震的复发概率.结果表明,交城断裂带北段潜在地震最大震级为Ms7.2级,而未来50a、100a、200a发生Ms7.2级地震的概率分别为2.1％、4.0％和7.9％.

Occurrence Probability Evaluation of the Largest Potential Earthquake Along Northern Segment of Jiaocheng Fault Zone

By quantitative research on Jiaocheng fault zone in Taiyuan target region,and especially the detailed investigation and systematic analysis on paleoearthquake in Jiaocheng fault zone,we established the recurrence mode and probability models of Jiaocheng fault zone that reflect the seismic,geological and kinemics characteristics.Based on regression relationship between magnitude and surface rupture length,between magnitude and source rupture length,between magnitude and rupture-area for seismogenic active faults,and between magnitude and seismic moment,we estimated that the maximum potential earthquake magnitude for Northern segment of Jiaocheng fault zone is M7.2,and the recurrence probability of surface rupturing earthquake （Ms7.2）is 2.1％ in the coming 50 years,4.0％ in the coming 100 years,and 7.9％ in the coming 200 years.