中国近海天然气成因类型及运聚特征  

Genetic types and migration-accumulation characteristics of natural gas

作　　者：邓运华 刘丽芳 沈朴 DENG Yunhua;LIU Lifang;SHEN Pu(CNOOC Research Institute Ltd.,Beijing 100028,China)

机构地区：[1]中海油研究总院有限责任公司,北京100028

出　　处：《中国海上油气》2024年第6期1-12,共12页China Offshore Oil and Gas

基　　金：“十三五”国家科技重大专项“近海大中型油气田形成条件及勘探技术(三期)(编号:2016ZX05024)”部分研究成果。

摘　　要：中国近海主要含气盆地(凹陷)有3盆4凹,即琼东南盆地、莺歌海盆地、东海盆地、白云凹陷、惠州凹陷、渤中凹陷和辽中凹陷,大量资料揭示中国近海天然气的成藏地质条件复杂,气源岩成因类型多样,生气强度、排气效率变化大,汇-运方式不同,成藏主控因素亦不同,这就要求勘探研究的重点应随之变化。中国近海新生代含气盆地内主要发育3类气源岩:第一类为海陆过渡相煤系气源岩,有机质丰度高、生气强度大,断层-砂体是主要汇-运通道,断背斜是主要的聚气圈闭,煤系气源岩规模是成藏主控因素;第二类是滨浅海环境陆源海相气源岩,有机质丰度较低、生气强度较小,泥底辟是重要的汇-运通道,底辟背斜和深水水道岩性圈闭是主要的聚气圈闭,汇-运通道是成藏主控因素;第三类是中-深湖相泥质气源岩,有机质丰度中等、生气强度较高,不整合面-砂体是主要汇-运通道,潜山和披覆背斜是重要的聚气圈闭,烃源岩热演化程度是成藏主控因素。The major gas-bearing basins(sags)in the offshore areas of China include three basins and four sags,namely the Qiongdongnan Basin,Yinggehai Basin,East China Sea Basin,Baiyun Sag,Huizhou Sag,Bozhong Sag,and Liaozhong Sag.A considerable amount of data reveals that the geological conditions for natural gas accumulation in the offshore areas of China are complex.The genetic types of gas source rocks are diverse;the gas generation intensity and the gas expulsion efficiency vary significantly;the accumulation and transportation patterns are different,and the main controlling factors for gas accumulation differ.This requires that the focus of exploration research should change accordingly.In the Neogene gas-bearing basins in the offshore areas of China,three main types of gas source rocks are developed:The first type is the coal-measure gas source rocks in the transitional marine-terrestrial facies,featuring high organic matter abundance and strong gas generation intensity.Fault-sand bodies are the main accumulation and transportation channels,and faulted anticlines are the main gas accumulation traps.The scale of the coal-measure gas source rocks is the main controlling factor for gas accumulation.The second type is the terrestrial-marine gas source rocks in the littoral and shallow sea environments,with relatively low organic matter abundance and weak gas generation intensity.Mud diapirs are important accumulation and transportation channels,and diapir anticlines and lithologic traps in deep-water channels are the main gas accumulation traps.The accumulation and transportation channels are the main controlling factors for gas accumulation.The third type is the argillaceous gas source rocks in the medium-deep lacustrine facies,with moderate organic matter abundance and relatively high gas generation intensity.Unconformity-sand bodies are the main accumulation and transportation channels,and buried hills and draping anticlines are important gas accumulation traps.The degree of thermal evolution of hydrocarbon source roc

关 键 词：中国近海 天然气 气源岩 成因类型 运聚特征 成藏主控因素 

分 类 号：TE121.3[石油与天然气工程—油气勘探]