珠江口盆地南部深水区CO2对天然气成藏影响的探讨StudyEffectof.PDF

珠江口盆地南部深水区CO2 对天然气成藏影响的探讨 1 1 2 2 2 孙金山 ，代一丁 ，姚振河 ，刘 鑫 ，杜克拯 （1. 中海石油深圳分公司勘探部，广东深圳2. 中海能源发展股份有限公司， 天津 300452 ） 摘要：珠江口盆地深水区发现了CO2 含量较高的烃类气藏和纯CO2 气藏，有机成因的烃类气体与无机成因的CO2 气体聚集在相同圈闭相同层位中。无机幔源型CO2 是上新世以后通过深大断裂或火山伴生断裂向上运移、然后在 高效疏导层中横向运移，在烃类气体聚集成藏过程中混入或者取代早期形成的油气藏中的油气而形成的。火山伴 生断裂展布、火山活动期次和油气生成充注时期是深水区天然气成藏的关键因素，勘探时要远离火成岩出露区及 伴生断裂带、避开以高效输导砂岩层与基底大断裂及伴生断层相连的构造带和圈闭。 关键词：深水区；CO ；无机幔源型；基底断裂；烃类气体 2 Study Effect of CO2 on Gas Accumulation in South Pearl-river Mouth Basin Deepwater Area 1 1 2 2 2 SUN Jinshan , DAI Yiding , YAO Zhenhe , LIU Xin , DU Kezheng （1. Shenzhen Branch of CNOOC Ltd., Shenzhen, 518067, China; 2. CNOOC Energy Technology Services Ltd., Tianjin, 300452, China) Abstract: Hydrocarbon gas reservoir with abundant CO2 and pure CO2 gas reservoir are found in deepwater area of Pearl-river mouth basin. Organic genetic hydrocarbon gas and Inorganic CO2 gather in the same trap and layer. CO2 of Inorganic mantle type was migrated upwards after Pliocene along deep large faults and volcanic-associated faults, and then along the horizontal direction to the efficient carrier bed. Finally, it was mixed into or replaced the oil and gas of oil-gas reservoir formed early in the process of hydrocarbon gas accumulation. The distribution of volcanic-associated faults and the times of volcanic activity and hydrocarbon generation and filling are critical factors to gas accumulation in