渤海湾盆地东濮凹陷天然气成藏条件与富集规律

渤海湾盆地东濮凹陷具有下第三系和上古生界2套烃源岩,生烃中心控制着气藏分布,构造特征控制着天然气的聚集,盐岩、厚层泥岩盖层有利于天然气藏的保存,生、储、盖组合关系决定了天然气纵向上的分段性。深层高异常压力和次生孔隙发育带是天然气富集高产的重要条件。东濮凹陷天然气分为上古生界煤成气和下第三系凝析气2种成藏模式,具有晚期成藏和幕式成藏的特点。东濮凹陷目前天然气剩余资源量较大,是中国东部重要的天然气勘探开发阵地,下一步应以下第三系凝析气藏和上古生界煤成气藏作为勘探的重点。 

THE RESERVOIR-FORMING CONDITION AND ENRICHMENT RULE OF THE NATURAL GAS IN THE DONGPU DEPRESSION, THE BOHAIWAN BASIN

There are two types of gas source rocks in Paleogene and Upper Paleozoic in the Dongpu Depression,the Bohai wan Basin.The distribution of the natural gas reservoirs are controlled by the center of hydrocarbon generation.The accumulations of the natural gas are controlled by the tectonic characteristics.The salt rock and thick mud rock are propitious to the preservation of the natural gas.Source bed,reservoir and cap rock determine the natural gas's subsection characters in portrait.The high abnormal pressure and secondary pore zone in depth are important conditions of the natural gas enrichment and high yield.There are two reservoir-forming modes of the natural gas in the Dongpu Depression,i.e.Upper Paleozoic coal-formed gas and Paleogene condensate gas.They are characterized by the later period and episodic reservoir-forming.The residual resources of the natural gas is bigger at present in the Dongpu Depression.It is an important exploration area of the natural gas in the eastern China.The Upper Paleozoic coal-formed gas and Paleogene condensate gas is the stress in the future.