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南海的形成揭示了大陆边缘张裂和盆地形成的复杂模式,尽管已经进行了广泛研究,但是关于基底岩石和深海盆沉积层的精确年代数据还很缺乏,这使得对南海张裂年代的估计存在很大的误差,对张裂机制和历史的各种假设没有得到验证。同时只有对南海的张裂过程有了精确地分析与刻画,才能更好地理解西太平洋边缘海盆地的形成以及它们在印支块体受印度—欧亚板块碰撞而向东南挤出、青藏高原隆升中可能起到的作用。2009年正式提交的国际综合大洋钻探计划(IODP)建议书735-Full建议在南海深海盆内的4个站位上实施钻探。这4个站位分布在南海盆地4个不同的次级构造单元上(南海东北部、西北次海盆、东部次海盆和西南次海盆),这样的站位设计会确保完成本建议书的整体研究目标,即揭示南海的张裂历史和它对晚中生代以来东南亚构造的启示。位于南海盆地最东北部的站位有助于确定该区域地壳的属性和验证古南海是否存在,位于西北次海盆的站位可能会提供南海的最早张裂年代,另外2个分别位于东部次海盆和西南次海盆的站位将重点确定2个次海盆的绝对年龄、基底矿物成分与磁化率以及2个次海盆的相对张裂次序。这些站位的水深大约在2910～4400m,钻探深度预计到海底以下大约700～2200m,总的钻透深度为5959m,其中5359m穿透沉积层,另外600m或400m钻入基底。所有这些站位的位置是由已有的地球物理观测数据所确定,目前计划收集更多的地质与地球物理数据以满足IODP对井位调查数据的要求。
The formation of the South China Sea reveals a complex pattern of continental margin fractures and basin formation. Although extensive studies have been conducted, accurate chronological data on basement and deep-sea sediments are still scarce, leading to the estimation of the age of the SCS Large errors, various assumptions about the mechanism and history of tension have not been validated. At the same time, we can only understand the formation of the marginal sea basin in the western Pacific Ocean and their southeastern extrusion in the southeastern part of the Indosinian block by the collision of the India-Eurasian plate only with accurate analysis and description of the cracking process in the South China Sea. Uplift may play a role. The International Synthetic Ocean Drilling Program (IODP) Recommendation 735-Full, officially presented in 2009, recommends drilling at 4 stations in the deep-water basin of the South China Sea. These four stations are located on four different secondary structural units in the South China Sea Basin (northeastern South China Sea, northwestern sub-sea basin, eastern sub-basin and southwestern sub-sea basin). Such a station design will ensure the completion of the overall study of this Recommendation The goal is to reveal the history of the crack in the South China Sea and its enlightenment on the tectonics of Southeast Asia since the late Mesozoic. The stations located in the northeastern part of the South China Sea Basin help determine the properties of the crust in the region and verify the existence of the Gouth Sea. The stations located in the Northwest China Sea Basin may provide the earliest age of the South China Sea and the other two are located in the eastern sub-sea basin And the stations in the southwest sub-sea basin will focus on determining the absolute age of two sub-sea basins, the composition of basement minerals and magnetic susceptibility, and the relative order of two sub-sea basins. The depth of these stations is about 2910 ~ 4400m. The drilling depth is estimated to be about 700 ~ 2200m below the seafloor. The total penetration depth is 5959m, of which 5359m penetrates the sedimentary layer and another 600m or 400m drills into the basement. The location of all these stations is based on existing geophysical observations and plans are now under way to collect more geophysical and geophysical data to meet IODP requirements for well location survey data.