The morphological characteristics in the area off eastern Taiwan Island and their tectonic implication
- 作者：LIU Baohua（刘保华）；ZHENG Yanpeng（郑彦鹏）；WU Jinlong（吴金龙）；HAN Guozhong（韩国忠）；ZHANG Deyu（张德玉）
- 单位1：Key Laboratory of Marine Sedimentology and Environmental Ceology,First Institute of Oceanography,State Oceanic Administration
- 语种：英文
- 作者关键词：Taiwan Island；morphological characteristics；tectonic implication
- 起始页：200
- 总页数：10
- 经费资助：Supported by the National Oceanic Key Program
- 刊名：海注沉积与环境地质国家海洋局重点实验室研究年报
- 是否内版：否
- 主编：石学法；孟宪伟；刘保华
- 期刊索取号：P371.0691672003-2004
摘要
On the basis of bathymetric data and other geological and geophysical data obtained duringthe first survey conducted by Chinese mainland in the area off eastern Taiwan Island from May to Junein 2000,the morphological features of the region,the tectonic control to the seafloor topography andtheir tectonic implication were studied and discussed.The results have revealed that both the slopezone of the Ryukyu Arc and the Ryukyu Trench present a typical morphotectonic characteristic con-trolled by the trench-arc system in the West Pacific Ocean.At the slope of eastem Taiwan Island theisobathic lines parallel the coastline and distribute densely in nearly N-S direction and the slope gra-dient of topography is large.Such a unique feature is attributed to the collision of the Luzon arc andEurasia continent.In the Huatung Basin,turbidity fans and submarine canyons are well developed,the formations of which are mainly related to the steep topography of the slope of the Luzon arc and theabundant supply of sediments. These submarine canyons are controlled by basement highs and strike-slip faults. At eastern side and westem side of the Gagua Ridge,both the water depth and morpho-logical features are different,but the basement of Gagua Ridge belongs to the Huatung Basin.Theeastern side of the Gagua Ridge (123°12′E) is corresponding to the boundary of two plates with dif-ferent ages.In the West Philippine Basin,linear ridges and troughs in a NW trending are identified,which are dissected by a N-E trending transform fault.According to the seafloor topography fea-tures,the direction of the transform fault and the magnetic anomaly lineations,the seafloor of this re-gion was formed during 60-45Ma B.P.when the West Philippine Basin was spreading alongNE-SW relative to present orientation.