台湾岛以南海域新近纪的弧—陆碰撞造山作用  

ARC-CONTINENT COLLISION OROGENY IN OFFSHORE TAIWAN DURING NEOGENE

作　　者：丁巍伟[1] 杨树锋[2] 陈汉林[2] 程晓敢[2] 吴能友[3] 

机构地区：[1]国家海洋局海底科学重点实验室,杭州310012 [2]浙江大学地球科学系,杭州310027 [3]国土资源部广州海洋地质调查局,广州510075

出　　处：《地质科学》2006年第2期195-201,共7页Chinese Journal of Geology(Scientia Geologica Sinica)

基　　金：国家重点基础研究发展规划(973计划)资助项目(G2000046704)。

摘　　要：台湾岛以南海域(台南滨海)弧—陆碰撞带位于欧亚板块、菲律宾海板块和南海的结合部位,是新近纪弧—陆碰撞研究的理想场所。本文通过对南海973航次在该区域的多道地震剖面的解释,认为台南滨海弧—陆碰撞带增生的火山—沉积楔由恒春海脊和高屏斜坡两部分组成,前者是菲律宾海板块的增生楔,后者是欧亚板块的增生楔,在增生楔体和火山弧之间是作为弧前盆地的北吕宋海槽。自中新世中期以来,南海洋壳开始沿着马尼拉海沟向菲律宾海板块俯冲,形成活动大陆边缘的增生部分———恒春海脊;与此同时菲律宾海板块开始向北西方向移动,前缘的吕宋岛弧距今6.5Ma以来朝着亚洲陆缘斜向汇聚,形成了被动大陆边缘的增生部分———高屏斜坡。由于菲律宾海板块和欧亚板块之间的斜向汇聚,弧—陆碰撞具有穿时性,造山作用首先发生在台湾岛的北部,然后向南部及台南滨海发展。The offshore Taiwan arc-continent collisional orogen was situated in the conjunction area of the Eurasian plate, the Philippine Sea plate and the South China Sea, which was created in Neogene. The structural geometry and kinematics of the Taiwan accretion prism were studied using multi-channel seismic profile of no. 973 survey. The geological evidence showed that the accretionary prism caused by the collison was consisted of two distincet structural parts： the prisms caused by the arc-continent collision and by the subduction of South China Sea respectively. In the studied area, the two main units were the Gaoping Slope and the Hengchun Ridge. From the Middle Miocene the South China Sea began to subduct beneath the Philippine Sea plate along the Manila Trench, and the Hengchun Ridge came into being. The Philippine Sea plate also moved northwestwards and collided obliquely with the Eurasian continent since 6.5 Ma, the arc-continent collision resulted in the Gaoping Slop west of the Hengchun Ridge, and the both made up the offshore Taiwan accretionary prism. Compared with the onland geology, the offshore Taiwan accectionary prism had a similar and continuous structural characteristics. They had the same tectonic mechanism but varied deformation history, i.e. the collision firstly began in the north part of Taiwan, then propagated southwards, so the north Taiwan Island experienced much longer deformational history.

关 键 词：弧-陆碰撞 南海 斜向汇聚 新近纪 台湾岛以南 

分 类 号：P541[天文地球—构造地质学]