岩溶洞穴沉积物的地震记录浅析

Primary study on seismic record from speleothems in caves

洞穴沉积物不仅具有旅游开发价值,而且蕴含了丰富的古气候环境信息,同时也是地震信息的存储器,是研究地震遗迹的良好材料。近10多年,在西南地区开展洞穴资源调研、古气候环境研究的期间,观察到一些洞穴沉积物的特殊坍塌现象,以及2008年5月12日四川汶川8级地震中岩溶洞穴沉积物发生破裂、坍塌等现象,认为它们与地震密切相关。本文利用洞穴沉积物中保存或记录的新、老地震印迹、铀系测年数据等,来恢复史前的地震事件和史载资料未记录的地震事件,并对地震事件发生的时间、强度进行对比等。洞穴沉积物中记录的地震印迹可为研究地震历史提供对比证据,填补历史丢失的地震记录,并能对未来地震的监测以及预报提供一个新的视角。

Speleothems are of not only value for tourism development,but also rich information in paleo-climate and paleo-environment,and also a recorder for earthquake information providing good material for earthquake vestiges study.In the recent ten years,some special speleothem collapse has been discovered in cave.Some fracture,speleothem collapse in cave occured or were produced after the earthquake of magnitude 8.0 in Wenchuan County,Sichuan,China,at 14：28,on May 12th,2008,suggesting the collapse is closely related with earthquake activities.This paper recover the prehistoric earthquake events that not recorded in historic data,and compare the time and intensity of the earthquake events,according to the vestiges recorded in the speleothem collapsed materials by new and old earthquake and the U-series dating age etc.The vestiges recorded in the speleothem collapsed materials in cave can provide relevant evidence and proof for studying the earthquake history,supply the lost historic records of earthquakes,and provide a new perspective for earthquake monitoring and forecasting in the future.