新生地震破裂带的识别类型划分及其地震地质意义

New-generated Seismic Rupture Zone:Recognition,Type Division and Significance in Seismogeology

地质研究表明:地表地质、地貌、深部地球物理场和地震活动时空分布等可作为鉴别新生地震破裂带的主要地震地质标志。地质和实验的研究还揭示,新生地震破裂带按其形成和破裂过程可分为预破裂-孤立型、准破裂-断续型和大破裂-贯通型3类。在预破裂-孤立型的破裂带内,以中强地震和弱震活动为主;处于准破裂-断续型的破裂带,带内强震频度增高、强度增大,甚至出现带内最高级别地震活动;而大破裂-贯通型的新破裂带是破裂的成熟地段,带内地震活动强度和持续时间则依带内本构条件和区域构造应力强度而别。

Based on the surface geological and geomorphological survey and the analysis of spatial\|temporal image of seismic activity,the main indicators for identifying the new\|generated seismic rupture zone (NSRZ) are proposed.It is concluded that the formation and evolution of NSRZ can be divided into three stages:pre\|rupture—isolated,sub\|rupture—discontinuous and major\|rupture—continuous.The seismic activity and surface rupture caused by strong earthquake in the pre\|rupture—isolated rupture zone only show the character of buried linear.The kind of rupture zone is characterized by moderately strong earthquakes and small earthquakes,having few disastrous earthquakes.The frequency of strong earthquakes increases for sub\|rupture—discontinuous rupture zone and sometimes the largest earthquake in the zone can happen,but the whole zone is discontinuous.The recognition and type division of NSRZ are also discussed.