摘要
断层泥是断裂活动信息的重要载体,其中石英碎砾微形貌特征的识别和统计,可以提供断裂活动的年代学证据。在野外调查的基础上,对西秦岭白龙江断裂带西段尼什峡剖面进行了系统的断层泥样品采集,共采集22件样品全部进行了石英碎砾提取和扫描电镜微形貌观察统计,其中5件样品进行热释光测年。结果表明,该断裂带尼什峡段在晚近以来曾多次活动。活动始于上新世,早更新世至中更新世早期进入高峰期,晚更新世仍在活动,但全新世已不再活动。这一结论对于正确评价白龙江断裂带的活动规律及其对该区自然环境的影响具有重要参考意义。
Gouge is an important information carrier for fault activities and the surface texture of gouge quartz contains chronological information of the fault activity.Gouge quartz samples were collected from 22 gouge samples,which were sampled at the Nis gorge section of the Bailong River （BR） fault,western Qinling,and their micro-rextures were observed by SEM,besides,5 of the gouge samples were tested by thermo-luminescence dating.The results showed that BR fault has undergone a few periods of activity,started from the Pliocene,peaked in the early-Pleistocene to early mid-Pleistocene period,was active in the late-Pleistocene but wasn＇t in the Holocene.This finding is significant for evaluating the activities of BR fault and for assessing their impacts to the regional environment.
出处
《矿物岩石地球化学通报》
CAS
CSCD
北大核心
2014年第3期271-278,共8页
Bulletin of Mineralogy, Petrology and Geochemistry
基金
中国地质调查项目(1212011120072)
国家科技支撑项目(2011BAK12B09)
国家自然科学基金项目(41072269
41072070)
