On interseismic elevation changes observed near 75.5° E longitude in the NW Himalaya
On interseismic elevation changes observed near 75.5° E longitude in the NW Himalaya
复制标题
喜马拉雅山西北部东经75.5°附近观测到的震间高程变化
DOI：
10.1785/bssa0890030837
复制
发表时间：
1999
期刊：
影响因子：
--
通讯作者：
R. Chander
中科院分区：
文献类型：
--
作者：
V. Gahalaut;R. Chander
本文解释了喜马拉雅西北部东经75.5°附近帕坦科特-达尔豪西水准线上震间高程变化的观测结果。我们发现，这些数据与喜马拉雅会聚板块边缘这一段的大地震可能以类似于沿太平洋边缘俯冲带推断的方式发生的观点一致。在这两种情况下，主冲断带(MTZ)是板块边界断层(PBF)的倾角剖面，在大地震期间破裂，被锁定在地震间期，由于下伏岩石以局部板块会聚的速度俯冲，上覆岩石受到下倾阻力。我们估计，MTZ在水平线附近的下倾宽度可能只有25公里。我们还估计，在当前的地震间隔期，可能已经为该地区的下一次大地震积累了足够的应变。
We interpret in this article the available observations of interseismic elevation changes along the Pathankot-Dalhousie leveling line near 75.5° E longitude in the NW Himalaya. We find the data consistent with the view that the major earthquakes of this section of the Himalayan convergent plate margin may occur in a manner similar to that inferred for subduction zones along the Pacific rim. In both cases, the main thrust zone (MTZ), a dipwise section of the plate boundary fault (PBF), which ruptures during major earthquakes, is locked in the interseismic period, and the overlying rocks experience downdip drag due to subduction of underlying rocks at the local plate convergence rate. We estimate that the MTZ may have a downdip width of only 25 km in the vicinity of the leveling line. We estimate also that, in the current interseismic period, enough strain may have accumulated already for the next major earthquake of the region.