从GPS水平矢量场对中国及全球地壳运动的新认识  

NEW COGNITIONS ON THE GLOBAL AND CHINESE CONTINENTAL CRUSTAL MOVEMENTS FROM GPS HORIZONTAL VECTOR FIELDS

作　　者：马宗晋[1] 张培震[1] 任金卫[1] 冯锐[2] 张进[1] 

机构地区：[1]中国地震局地质研究所,北京100029 [2]中国地震局地球物理研究所数据中心,北京100031

出　　处：《地球科学进展》2003年第1期4-11,共8页Advances in Earth Science

基　　金：国家自然科学基金项目"中国大陆典型地区构造变形和现今构造应力场研究"(编号:49834002)资助

摘　　要：利用中国GPS矢量场和IERS公布的全球矢量场,对中国及全球地壳水平运动的状态进行了从全球到局部不同空间尺度的构造运动的描述和理解,其要点如下:①GPS矢量场定量地显示了中蒙构造区是全球大陆内变动最强的地区;②中蒙构造区(或中蒙次板块)内部可分出三级各具特色的构造区块、条块和地块;③中蒙西部区块呈大" ",3条边缘带都是地壳厚度陡变带,是结构性地震带,控制了全球大陆内2/3以上的8级地震;④中蒙东部构造区块是挤压型和伸展型大陆边缘最典型地区,GPS矢量场展现了现今向东的伸展蠕散运动;⑤中国西部2001年在昆仑山发生的8.1级地震与西部从GPS矢量场算得的视应变场中高应变带相关;⑥全球GPS矢量场揭示N/S半球之间存在明显的运动不协调带,该带(B带)直接表现为13条左列的走滑兼挤压断裂带,该带控制的强震活动与环太平洋俯冲带(A带)控制的地震自1897年以来交替活动已有七幕。讨论提出:①全球4个构造系(环太平洋构造系、洋脊构造系、北半球大陆高原构造系和环赤道构造系)是否与地球的N/S半球、0～180°半球的双重非对称有关?②全球GPS矢量场所描述的板块运动可否作为约束推算地幔三维运动的表层条件?Based on the GPS vector field of Chinese Continent and the global vector field issued by the IERS, we analyses the state of the global and Chinese continental crustal movements from global scale to regional scale, the results are:①The GPS vector fields show that the deformations of ChineseMongolian tectonic region are the strongest around the globe; ②There are threelevel tectonic units with different characteristics (Region, Strip and Block) divided from ChineseMongolian tectonic region (or ChineseMongolian subplate); ③The shape of the western ChineseMongolian Region is a large triangle, the three margins of this triangle are all important structural seismic zones controlling more than 2/3 earthquakes (Ms≥8) around the globe, moreover the thickness of the crust changes rapidly across these three margins; ④The eastern ChineseMongolian region is typical area of compressivetype and extensivetype continent margin, and the GPS vector field shows that this part is creeping eastwards; ⑤The earthquake (Ms=8.1) occurring in Kunlun mountain in 2001 is located in the strong strain area of visual strain field obtained from the GPS vector field; ⑥The global GPS vector field shows that the movements between N/S hemispheres are disharmonious, this disharmonious zone (B) is composed of 13 leftlateral strikeslip faults with somewhat compression. Based on the these mentioned above, two questions are discussed: ①Are the four global tectonic systems (circumPacific Ocean, Middle Ocean Ridges, plateaus of north hemisphere and circumEquator tectonic system) related with double dissymmetry of the earth?②Can the plate movement shown by GPS vector field be taken as the surface conditions constraining the 3D movement of the mantle?

关 键 词：地壳运动 GPS矢量场 地球双重非对称 三维地幔运动 板块运动 全球定位系统 

分 类 号：P553[天文地球—构造地质学] P228.4[天文地球—地质学]