南海新生代生物礁发育规律与油气勘探潜力  

Development regularity and hydrocarbon exploration potential of Cenozoic reef reservoir, South China Sea

作　　者：冯杨伟[1] 张功成 屈红军[3] 

机构地区：[1]中国地质调查局西安地质调查中心 [2]中海油研究总院 [3]西北大学地质学系

出　　处：《中国石油勘探》2016年第6期18-25,共8页China Petroleum Exploration

基　　金：国家科技重大专项"大型油气田及煤层气开发"(2016ZX05026-007);中国地质调查局油气地质调查专题"新疆东部石炭纪-二叠纪沉积相与沉积体系研究"(121201011000150012-05)

摘　　要：南海及周边地区新生代含油气盆地中生物礁大量发育,以区域地质、生物礁油气藏特征等资料为依据,综合分析南海海域新生代生物礁发育规律。研究结果表明:南海新生代生物礁的主要造礁生物为珊瑚藻,以发育远岸礁带为主。南海北部和南部生物礁类型较多,包括塔礁、台地边缘礁和块礁等,南海西部以台地边缘礁最为典型,南海东部主要发育塔礁。南海生物礁形成具有整体北早南晚且同一构造带内东早西晚的发育规律。生物礁都发育在盆地的次级正向构造带上。南海生物礁主要成礁期集中在中新世,有三大主成礁期,分别为早中新世、中中新世和晚中新世。南海海域生物礁伴随着海平面上升而发育,伴随着短暂的海退导致生物礁暴露。南海海域富烃凹陷分布广泛,生物礁储层储集性能优越,发育厚层海相泥岩优质区域性有效盖层,断层面和不整合面是良好的油气垂向运移的主要通道,超压提供了油气运移的动力,南海海域新生代生物礁油气藏前景广阔。Reefs are greatly developed in Cenozoic petroliferous basins in the South China Sea and its surrounding area. According to the collected data on regional geology and reef reservoirs, a comprehensive analysis was made on the development regularity of Cenozoic reefs. The results indicate that the Cenozoic reefs in the South China Sea were built from coralgals, and they are dominantly infralittoral reefs. In the northern and southern parts of South China Sea, there are diverse reefs, including tower reef, platform-edge reef and massive reef. In the western part, platform-edge reef is typical. In the eastern part, tower reef is dominant. Reefs in the South China Sea were developed earlier in the north than in the south across the region, and earlier in the east than the west within the same tectonic belt. All reefs reside on the secondary positive tectonic belts in basins. The reefs were mainly formed during the Miocene, consisting of three main periods, i.e. Early Miocene, Middle Miocene and Late Miocene. They grew with the sea level rising, and exposed after a transitory regression. Hydrocarbon-rich sags spread widely in the South China Sea, reef reservoirs provide excellent preservation conditions, and thick marine mudstone serves as regional effective seal. Moreover, fault surfaces and unconformities act as main pathways for vertical hydrocarbon migration, and overpressure offers a driving force for hydrocarbon migration. All these conditions suggest a bright exploration prospect for the Cenozoic reef reservoirs in the South China Sea.

关 键 词：南海 生物礁 新生代 发育规律 油气勘探潜力 

分 类 号：TE122.1[石油与天然气工程—油气勘探]