Through simulation experiment,analyzing gas components and isotope characteristics,clustering analysis and origin identification,research of different types of natural gas reservoirs in Dongpu Depression shows that two sets of hydrocarbon source rocks in the Paleogene and the Carboniferous-Permian in turn formed crude oil cracking gas,lacustrine mudstone late kerogen pyrolysis gas and coal-formed gas under conditions of high thermal evolution.Three main gas productions make the Dongpu Sag gas rich in deep.Based on identification and dynamic analysis of gas reservoir,the condensate gas reservoir and coal-formed gas reservoir have characteristics of near source accumulation,relay accumulation and type W distribution.Studying a typical gas reservoir,deep condensate gas and coal-formed gas enrichment is mainly affected by distribution source rocks of high thermal evolution,the favorable exploration areas of condensate gas reservoir by depth (＜4 350 m),slope (synsedimentary fault) and organic matter abundance (TOC＞0.8％) ("Three factors").The key areas of Paleogene deep condensate gas reservoir exploration are structural slopes of secondary hydrocarbon regional and deep reservoir "dessert" development area.Favorable exploration areas of coal gas are mainly concentrated in the upper Paleozoic coal source rock with thermal evolution degree of Ro＞2.0％ and gas-generating intensity greater than 20×108 m3/km2.So the central uplift and middle and lower parts of the slope would be the favorable targets for natural gas exploration.%通过实验模拟,气体组分及同位素特征分析,对东濮凹陷不同类型天然气藏进行了聚类分析,并对成因进行判识.明确了古近系和石炭—二叠系2套烃源岩,在高热演化条件下可依次形成原油裂解气、湖相泥岩干酪根晚期裂解气及煤成气,3种主要生气方式造就了东濮凹陷深层富气.成因判识及气藏动态过程分析表明,东濮凹陷凝析气藏及煤成气藏具有“近源聚集、接力成藏、W型分布”的成藏特征.结合典型气藏解剖,指出深层凝析气及煤成气的富集主要受高热演化烃源岩的分布控制,其中,凝析气藏的有利勘探区域受深度(小于4 350 m)、坡度(同沉积断层)、有机质丰度(TOC＞0.8％)(“三度”)控制,二次生烃区域斜坡构造部位及深层储层“甜点”发育区是古近系深层凝析气藏勘探重点领域.煤成气的有利勘探区域主要集中在上古生界煤系源岩Ro＞2.0％、生气强度大于20×108 m3/km2的区域,中央隆起带及斜坡中下部位为有利勘探区.
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