摘 要：首次提出原位油气藏的概念，把油气生成的原生地层中形成的具有商业开采价值油气资源的地层单元称为原位油气藏，能够生成烃类并能为原位油气藏提供储集空间的地层称为原生地层。分析了原生地层中有机质含量与原位油气藏的形成关系以及原生地层中烃类的相态与有机质热演化程度，探讨了有机质的数量、类型、热演化程度以及在有机质热演化过程中地层中不同状态的有机质（干酪根→液态烃（沥青）→湿气→干气）相互转化等因素对原生地层中油气的富集程度以及原位油气资源相态的控制作用。中国发育了海相、海陆过渡相到陆相等多种沉积环境条件下10余套富含有机质及页岩油气资源的泥页岩系，具备形成以页岩油和页岩气为主或油气共生特征的原位油气藏成藏条件和基础。原位油气藏中的原位油气资源作为重要的非常规油气资源将在今后的油气勘探工作中占据十分重要的地位。
关键词：原位油气藏；原生地层；非常规油气；页岩气；有机质；相态；热演化；资源潜力
中图分类号：P618.130.2 文献标志码：A
Characteristic and Forming Mechanism of Oilgas Trap in Source Strata and Its Resource Potential
TUO Jincai1， ZHANG Mingfeng1， WU Chenjun1，2， LIU Yan1，2， CHEN Ru1，2， XIONG Deming1，2
（1. Key Laboratory of Petroleum Resources Research， Institute of Geology and Geophysics， Chinese Academy
of Sciences， Lanzhou 730000， Gansu， China； 2. University of Chinese Academy of Sciences， Beijing 100049， China）
Abstract： Oilgas trap in source strata was put forward firstly； the trap was a kind of hydrocarbon resource strata unit with commercial exploitation value from original formation generating hydrocarbon； original formation could generate hydrocarbon and supply reservoir space for oilgas trap in source strata. The relationship between organic content and the formation of oilgas trap in source strata was analyzed， and phase state of hydrocarbon and thermal evolution degree of organic matter in original formation was explained. The controlling factors on the level of oilgas eichment and the phase state of oilgas resource in original formation were discussed， and the factors included abundance， type and thermal evolution degree of organic matter and the mutual transformation among different phase states of organic matter during thermal evolution （kerogen→liquid hydrocarbon （bitumen）→wet gas→dry gas）. In China， more than 10 sets of mudstone shale series rich in organic matter and shale oilgas resource developed in various sedimentary environments including marine facies， marinecontinental transitional facies， continental facies， etc.， so that oilgas trap in source strata could be formed with the characteristics of mainly shale oil and gas or symbiosis of oil and gas. Original oilgas resource from oilgas trap in source strata taken as unconventional one will occupy an important position in future oilgas investigation and exploration.
Key words： oilgas trap in source strata； original formation； unconventional oilgas； shale gas； organic matter； phase； thermal evolution； resource potential