地震统计区活动性参数与潜在震源区划分的关联性及对危险性估计的影响  

INTERRELATION BETWEEN SEISMICITY PARAMETERS AND DELIMITING POTENTIAL SEISMIC SOURCES IN A SEISMIC STATISTICAL REGION AND ITS INFLU- ENCE ON SEISMIC RISK ESTIMATION

作　　者：黄玮琼[1] 吴宣[1] 

机构地区：[1]中国地震局地球物理研究所,中国北京100081

出　　处：《地震学报》2005年第4期409-413,共5页Acta Seismologica Sinica

基　　金：地震科学联合基金(103051)资助

摘　　要：在考虑地震活动时空不均匀性的非均匀分布模型中,就地震统计区活动性参数不确定性在某些城镇产生地震动参数不确定性最大变化值异常区的问题,寻找出在100°～120°E、29°～42°N范围内,50年不同超越概率水平下地震动参数不确定性最大变化值异常区的分布特征.探讨了地震统计区活动性参数不确定性引起的场点危险性估计不确定性与潜在震源区划分的关联性以及异常区产生的原因.研究表明,在非均匀分布模型中,地震统计区活动性参数的不确定性对区内各场点危险性估计不确定的影响是不均衡的,其与潜在震源区划分方案有关,尤其在8级以上潜在震源区及其附近,往往会出现地震动参数不确定性最大变化值的异常区.而在均匀分布模型中,统计区内活动性参数的不确定性对各场点的影响是均衡的,各场点危险性估计的不确定性取决于场点的位置.一般位于统计区中部的场点,只与所在统计区的参数不确定性有关,而位于或靠近不同统计区的交界处,则可能同时受到几个统计区活动性参数不确定性的综合影响.In the paper, we have discovered the abnormal area distribution features of maximum variation values of ground motion parameter uncertainty with different probabilities of exceedance in 50 years within the range of 100°~120°E, 29°~42°N for the purpose to solve the problem that abnormal areas of maximum variation values of ground motion parameter uncertainties emerge in a certain cities and towns caused by seismicity parameter uncertainty in a seismic statistical region in an inhomogeneous distribution model that considers tempo-spatial nonuniformity of seismic activity. And we have also approached the interrelation between the risk estimation uncertainty of a site caused by seismicity parameter uncertainty in a seismic statistical region and the delimitation of potential sources, as well as the reasons for forming abnormal areas. The results from the research indicate that the seismicity parameter uncertainty has unequal influence on the uncertainty of risk estimation at each site in a statistical region in the inhomogeneous distribution model, which relates to the scheme for delimiting potential sources. Abnormal areas of maximum variation values of ground motion parameter uncertainty often emerge in the potential sources of M_u≥8 (M_u is upper limit of a potential source) and their vicinity. However, this kind of influence is equal in the homogeneous distribution model. The uncertainty of risk estimation of each site depends on its seat. Generally speaking, the sites located in the middle part of a statistical region are only related to the seismicity parameter uncertainty of the region, while the sites situated in or near the juncture of two or three statistical regions might be subject to the synthetic influences of seismicity parameter uncertainties of several statistical regions.

关 键 词：地震统计区 活动性参数 潜在震源区 异常区 等值线图 关联性 

分 类 号：P315.9[天文地球—地震学]