In the Songliao Basin and peripheral area, the neopaleozoic tectonic layers are recognized as the folding and metamorphic basement of Mesozoic and Cenozoic basins for a long time, so they are neglected in the oil exploration. By the study in the field and laboratory for about 3 years, it indicates that there is no regional metamorphism in the Upper Paleozoic of the study area except for the dynamitic contact metamorphose and thermal metamorphism with various degree in some areas. The preliminary investigation indicates that it exists four source rock layers from Carboniferous to Permian in the area, from upper to lower including: Upper Permian (Linxi Formation, Suolun Formation), Middle Permian (Zhesi Formation,Wujiatun Formation), Upper Carboniferous-Lower Permian (Benbatu Formation, Amushan Formation), Lower Carboniferous (Baijiadian Formation, Hongshuiquan Formation). Among them, the Upper Permian (Linxi Formation) and Middle Permian (Zhesi Formation) spread widely in the area, the max monolayer thickness of the black muddy rock from which gets to several hundred meters and the accumulated thickness from several hundred meters to several kilometers. The main organic geochemical indices (the organic carbonate, the maturity and the type of kerogen) reflect the source rocks from the two formations get the rank of middle or good. The two formations are the main generating hydrocarbon layers in the Carboniferous-Permian of the Songliao and peripheral area, which shows the good prospect of oil and gas resource, would become the new strategic succeed strata in the northeast oil and gas exploration region of China.%松辽盆地及外围地区晚古生代构造层因长期以来被视为中-新生代盆地的变质褶皱"基底"而受到油气勘探界的忽略.近4年的野外调查和室内研究结果表明.本区上古生界除局部遭受不同程度的动力接触变质或热力变质外,并没有发生区域变质作用.初步查明本区石炭系-二叠系在区域上分布4套烃源岩,自上而下为:上二叠统(林西组、索伦组)、中二叠统(哲斯组、吴家屯组)、上石炭统-下二叠统(本巴图组、阿木山组)和下石炭统(白家店组、红水泉组).其中上二叠统和中二叠统中的暗色泥岩单层最大厚度迭百余米、累计厚度迭数百米至千余米,区域分布广,依据有机地球化学主要指标(有机碳、成熟度、干酪根类型),综合评价为中等-好烃源岩,是本区上古生界2套区域主力生烃层系,具有良好的油气资源远景,可望构成松辽及外围地区油气勘探战略接替新层系.
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