南海及邻区中生代(晚三叠世—白垩纪)地层分布特征及含油气性对比  

Upper Triassic-Cretaceous sediment distribution and hydrocarbon potential in South China Sea and its adjacent areas

作　　者：夏戡原[1] 黄慈流[1] 黄志明[1] 

机构地区：[1]中国科学院南海海洋研究所

出　　处：《中国海上油气（工程）》2004年第2期73-83,共11页China Offshore Oil and Gas

基　　金：国家自然科学基金资助课题"南海东北部与台湾间的构造及海洋地球物理研究" ;中国科学院南海海洋研究所与中海石油研究中心勘探研究院合作科研项目"南海东北部与东南亚地区晚三叠世以来中生代地层的分布;构造和含油气性对比研究"部分研究成果

摘　　要：南海周边陆区晚三叠世—白垩纪地层分布及沉积相特征与板块碰撞拼合有关。南海北部陆区晚三叠世—白垩纪地层 ,特别是海相地层的分布与哀劳山—红河早印支期缝合带有关。上三叠统—下侏罗统有海相地层 (浅海海湾相或海陆交互相碎屑岩 )分布 ,而中、上侏罗统及白垩系为陆相地层。南海西部陆区晚三叠世—白垩纪地层 ,特别是海相地层的分布与昌宁—孟连—劳勿—文冬晚印支期缝合带有关 ,致使中南半岛西部、云南及西藏羌塘地区在晚三叠世—白垩纪时期具有相似的沉积特征 ,即中、晚三叠世沉积海相地层 ,其后地壳普遍隆起 ,海水退却 ,陆地范围扩大。南海南面的印度尼西亚、加里曼丹岛 ,东面的菲律宾、台湾岛以及南海东北部中生代地层的分布 ,与西藏雅鲁藏布缝合带、印尼巴里散缝合带、加里曼丹卢帕尔缝合带、菲律宾巴拉望缝合带有关 ,这些缝合带的缝合时间是晚白垩世—早第三纪 ,以致晚侏罗世—早白垩世地层为深海硅质岩及浅海灰岩地层 ,其后地层为陆相地层。台西、台西南和礼乐等 3个盆地的下白垩统烃源岩有机质含量一般为中等 ,有机质类型主要为Ⅲ型 ,成熟度中等 ,以产气为主 (已在台西南盆地下白垩统钻获天然气 ) ;上三叠统—下侏罗统烃源岩有机质含量一般较高 ,有机质类型主要为Ⅲ型 。The Upper Triassic-Cretaceous distribution and sedimentary facies onshore around South China Sea is controlled by the plate collision and amalgamation in the adjacent areas. For the northern South China Sea, these onshore sedimeuts, especially the marine sediments, can be related to the early Indosinian Suture of Ailaoshan-Red River. During Late Triassic to Early Jurassic, marine sediments formed (sallow_bay facies or alternating continent_marine facies), and only continental facies deposited during Middle Jurassic to Cretaceous. For the western South China Sea, these onshore sediments, especially marine sediments, are controlled by the Late Indosinian Suture of Changning-Meglian-Raub-Bentong. During Late Triassic to Cretaceous, a set of similar sediments formed in the western part of Zhongnan peninsulaYunnan and Qiangtang area, and is characterized by Middle-Late Triassic marine sedimentation and there after wide crust uplifting with a regression. For Indonesia and Kalimantan in south of South China Sea, Philippines and Taiwan in east of South China Sea and the northeastrrn South China Sea, the Mesozoic sediments are related to several sutures, such as the Yaluzangbu (Tibet), the Woyla(Indonesia), the Lupar (Kalimantan) and the Palawan (Philippines). The ages of these sutures are Late Cretaceous to Early Tertiary, and therefore the Upper Jurassic to Lower Cretaceous are deep_sea sil_ icalites and shallow_sea carbonate deposits, and the Upper Cretaceous is continental sediments. In West Taiwan, Southwest Taiwan and Liyue basins, the Lower Cretaceous source rocks are middle in organic content and maturity, and the organic matter is type Ⅲ and gas_prone. In Southwest Taiwan basin, natural gas has been seen in Lower Cretaceous. The Upper Triassic-Lower Jurassic source rocks also contain organic matter of type Ⅲ, but are higher in maturity and less hydrocarbon potential than the Lower Cretaceous due to its overmaturation in most areas. In Southwest Taiwan and Liyue basins, gas and condensates were found in Oli

关 键 词：南海 地层 分布特征 石油 天然气 白垩纪 印支运动 

分 类 号：P618.13[天文地球—矿床学]