基于高精度GPS监测龙门山断裂带中段及邻区现今地壳活动性研究  

Research of the activity along the central segment of the Longmenshan active faults and adjacent regions based on the high precision GPS monitoring

作　　者：张清志[1] 唐文清[1] 刘宇平[1] 李军[1] 

机构地区：[1]成都地质矿产研究所,成都610082

出　　处：《地球物理学进展》2013年第1期190-198,共9页Progress in Geophysics

基　　金：青藏高原东缘地壳形变GPS监测(1212011140013)项目资助

摘　　要：高精度GPS测量是研究现今地壳运动和地壳形变的重要手段之一.龙门山断裂带一直备受地质学者关注,尤其是2008年5月12日汶川大地震发生以后,对龙门山断裂带的研究提出了许多新的认识.汶川大地震后通过对1991年至2008年龙门山断裂带长期GPS监测成果(0.3～7mm/a)的分析、研究总结后认为这种低速率断层经过长期缓慢的能量积累,同样能够产生大地震;近期(2008～2010年)GPS观测数据结果揭示,龙门山断裂带中段及邻区的地壳运动速率由地震前的0.3～7mm/a,提高到4～57mm/a,分析认为在观测期内龙门山断裂带中段及邻区正处于一个震后应力释放期,这种应力释放可能还将持续相当长时间,影响着龙门山断裂带现今的活动性.今后一段时间龙门山断裂带可能仍处余震的高发期,需引起关注!对于今后龙门山活动性是否已经进入一个新的活动期,还需要进一步长期的高精度监测来确认、修正.The high precision GPS measurement is the important methods for studying the crustal movement and crustal deformation. The activity of the Longmenshan fault zone is attentioned by geologician, After the earthquake at 12 May, 2008 , at the same time, the research on the Longmenshan fault zone has many new ideas. Based on further analysis of results（0. 3 - 7 rnm/a） of the high precision GPS surveying along the Longmenshan fault zone between 1991 and 2008, with long-term gradually energy cumulation , this type of low-rate the fault, also can cause a serious earthquake, this paper documents some new opinions on the activity along the central segment of the Longmenshan fault zone and adjacent regions after the 2008 earthquake. The GPS observation data between 2008-2010 reveals that the velocity of crustal movement along the central segment of the Longmenshan fault zone and adjacent regions increase to 4457 mm/a from 0. 3-7 mm/a before the earthquake, which shows that it is in a active period and in a aftershocks stage after the earthquake, that should still be deeply concerned.

关 键 词：GPS 龙门山断裂带 地震 地壳活动性 

分 类 号：P315[天文地球—地震学] P541[天文地球—固体地球物理学]