Interplate coupling beneath NE Japan inferred from three-dimensional displacement field
Interplate coupling beneath NE Japan inferred from three-dimensional displacement field
复制标题
DOI：
10.1029/2004jb003203
复制
发表时间：
2006-04
影响因子：
--
通讯作者：
Yoko Suwa;S. Miura;A. Hasegawa;Toshiya Sato;K. Tachibana
中科院分区：
文献类型：
--
作者：
Yoko Suwa;S. Miura;A. Hasegawa;Toshiya Sato;K. Tachibana
[1]日本东北弧位于典型的俯冲带，是一个地震活跃区，多次发生大型板间地震。全国性的全球定位系统网络使人们有可能以前所未有的详细程度调查地壳变形;然而，垂直位移不如水平位移准确，而且还没有被用来约束板间耦合模型。在这项研究中，GPS载波相位数据进行了分析，以估计三个组成部分的网站位移。结果表明，日本海沿岸沿着隆起，太平洋沿岸沿着下沉。利用垂直速度和水平速度作为大地测量反演的数据，建立了一个新的板间耦合模型，解释了1997 ~ 2001年地震间隔期的水平速度和垂直速度。该模型表明，强耦合在该地区关闭宫城和在该地区关闭青森通过该地区关闭十胜，包括凹凸不平的地区。据地震学估计，日本东北部板块边界上的闭锁断层带的下倾极限在50-60 km的深度，本研究得出的滑动亏损分布表明，过渡带向下延伸到约100 km的深度。
[1] The northeastern Japan arc is located in a typical subduction zone and is a seismically active region where large interplate earthquakes have occurred repeatedly. The nationwide GPS network has made it possible to investigate the crustal deformation in unprecedented detail; however, vertical displacements are less accurate than the horizontal ones and have not been used to constrain interplate coupling models. In this study, GPS carrier phase data are analyzed in order to estimate three components of site displacements. The result indicates uplift along the Japan Sea coast and subsidence along the Pacific Ocean coast. Using the vertical site velocities together with the horizontal ones as the data for a geodetic inversion method, a new model of interplate coupling is constructed to explain both the horizontal and vertical velocities for the interseismic period from 1997 to 2001. The model demonstrates strong coupling in the area off Miyagi and in the area off Aomori through the area off Tokachi, including the areas of asperities. The downdip limit of the locked fault zone on the plate boundary has been estimated seismologically to be at a depth of 50–60 km in northeastern Japan, and the distribution of slip deficits derived in this study indicates that the transition zone extends down to a depth of about 100 km.