临清坳陷东部煤成气藏的主控因素及成藏模式

临清坳陷是渤海湾盆地油气资源的重要勘探研究区，其煤成气藏潜力大，但研究程度较低。从多角度入手，通过解剖典型的煤成气探井，分析研究了临清坳陷东部煤成气藏的主控因素及成藏模式。研究结果显示：该区煤岩以Ⅲ型干酪根为主，暗色泥岩以Ⅱ₂-Ⅲ型干酪根为主，易于生气（油）；油气运移以近源输导为主；煤成气成藏主要受控于圈闭的赋存条件、油气输导、生储盖组合以及优质烃源岩分布等4个方面；成藏模式主要划分为源内成藏和源外成藏两种模式，其中源内成藏模式是今后该区勘探的主体，源外成藏的I型为进一步攻克对象。

Key factors controlling reservoir forming and accumulation model of coal-derived gas in eastern part of Linqing depression

Linqing depression is regarded as an important oil-gas exploration and study area in Bohai Bay basin. Low exploration level and big potential made research work to be significant in this area. The paper studied main factors controlling reservoir forming in different aspects including typical reservoir analysis, and summed up accumulation models for coal-derived gas in Linqing depression. Main source rocks in Linqing depression are coal and dark mudstone, among which coal bed was classified as type-III kerogen inclined to generate gas, and mudstone of II2-III-type kerogen apt to generate oil as well as gas. Hydrocarbon migration is mainly featured by short connecting passages. Development of coal-derived gas reservoir is mainly controlled by trap evolution, gas migration, assemblage of source rock, reservoir bed and cap rock, as well as distribution of good source rock. Research indicated that there are two types of coal-derived gas accumulation models namely reservoir model of the interior of source rock and the exterior of source rock. Among them, reservoir model of the interior of source rock is main targets of exploration henceforth, while the I-type of reservoir model is to be studied further.