库赛湖—玛曲断裂带东、西大滩段全新世活动特征及古地震的研究

PRELIMINARY STUDY ON PALEOEARTHQUAKES AND THE CHARACTERISTICS ALONG THE SECTIONS OF DONGDATAN AND XIDATAN ON KUSAI LAKE-MAQU FAULT ZONE DURING HOLOCENE PERIOD

通过对野外调查资料的分析认为:库赛湖—玛曲断裂带东、西大滩段全新世以来具有多次强烈活动,表现为断错晚第四纪地层,断错山脊、水系、河流阶地以及冰水扇等一系列地貌现象。根据对断裂带上古地震破裂带的研究,全新世以来在该段曾发生过三次7.5级左右的古地震事件。

Kusai lake -Maqu fault,the major active fault zone in Qinghai-Tibet Plateau is found out of strong seismicities in Holocene through geological and geomorphological investigation , especially on its section of Dongdatan and Xidatan ,in forms of offsetting Late Quaternary stratum , ridge , water system , river terrace , outwash fan and so on . According to the surface rupture zone of paleoearthquakes along the fault ,it is estimated that there at least occurred three large paleoearthquake events (M≥7. 5) since Holocene.