摘要
Oil-gas 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 oil-gas trap in source strata.The relationship between organic content and the formation of oil-gas 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 oil-gas enrichment and the phase state of oil-gas 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 oil-gas resource developed in various sedimentary environments including marine facies,marine-continental transitional facies,continental facies,etc.,so that oil-gas trap in source strata could be formed with the characteristics of mainly shaleoil and gas or symbiosis of oil and gas.Original oil-gas resource from oil-gas trap in source strata taken as unconventional one will occupy an important position in future oil-gas investigation and exploration.