南沙地区下第三系沉积特征及其与含油气性的关系  

CHARACTERISTICS OF THE PALEOGENE DEPOSITS IN NANSHA WATERS AND THEIR RELATIONS TO THE PETROLEUM POTENTIAL

作　　者：阎贫[1,2] 刘海龄[1,2] 邓辉[1,2] 

机构地区：[1]中国科学院边缘海地质重点实验室,中国科学院南海海洋研究所,广东广州510301 [2]中国科学院广州天然气水合物研究中心

出　　处：《大地构造与成矿学》2005年第3期391-402,共12页Geotectonica et Metallogenia

基　　金：十五科研院所社会公益研究专项(2001DIA50041);中国科学院知识创新工程重要方向项目(KZCX3-SW-224;KZCX2-SW-117;KGCX2-SW-309);中国科学院南海海洋研究所创新基金领域前沿项目(LYQY200312);国家重点基础研究发展规划项目(G2000046702-04);国家基金项目(40376012)的资助.

摘　　要：通过南沙调查地球物理资料和围区区域地质资料的对比,分析了南沙海区的中生代和新生代地层的划分,指出南沙东部钻井和拖网揭示的中生代上部沉积地层(白垩系)很可能延伸到南沙中部。南海裂谷期间形成的下第三系具有明显的裂谷充填特征,其构成生油岩主体。南沙西南及西部的下第三系受到走滑、拉张和挤压的影响,构造复杂,圈闭多,规模大,是主要的生油和储集岩层。在南沙东北部充填在裂谷中的下第三系受到不同程度的积压,是重要的储集岩层。南沙东部地区也是水合物形成的有利地区。With the geophysical data collected in Nansha Waters being correlated with the regional geological data from adjacent areas, the Mesozoic to Cenozoic sedimentary sequences were analyzed. It was noted that the Upper Mesozoic strata （mainly Cretaceous） as revealed by drill or dredge from the eastern Nansha waters might extend into the hinterland of the Nansha Waters. In the southwest and west parts of the Nansha Waters, the Paleogene sediments have suffered from strike-slipping extension and compression, and are comprised of the main oil source rocks in numerous large traps over the area. In the eastern part, the Paleogene infilling in the rift structure has been altered by compression and also became important reservoir rocks. The eastern margin of Nansha Waters shows promising prospect for gas hydrates as well.

关 键 词：南沙 下第三系 含油气性 沉积特征 

分 类 号：P618.13[天文地球—矿床学]