通过大量的实验资料,首次系统地对勘探新区大巴山、米仓山南缘不同时代的烃源岩特征进行了综合研究。指出:下寒武统、下志留统、下二叠统是主要的烃源岩发育层系;与四川盆地类似,新区内Ⅰ级烃源岩有机碳含量较高,有机质类型好,主要为Ⅰ型―Ⅱ_1型干酪根,且横向分布稳定,现今均处于过成熟阶段,以生气为主。烃源岩的热演化史研究表明:古生代时期源岩热演化程度较低,源岩的油气生成相态明显受株罗系地层沉积厚度的控制;下寒武统烃源岩成油高峰期在三叠纪末―株罗纪初,气态烃的大量形成时间为早侏罗世末―晚侏罗世;下志留统烃源岩成油高峰期在早侏罗世―中侏罗世,气态烃大量形成的时间为中侏罗世末―白垩世;下二叠统烃源岩成油高峰期在中侏罗世―晚侏罗世,气态烃大量形成的时间为晚侏罗世―白垩纪。

This paper is by the synthesis analysis to a large number of geochemical data, and has systematically research to the source rock features of the different age of the south of the Dabashan and Micangshan, points out major source rock are C1S1 and P1. Similar to the Sichuan Basin, in this area, the precentage of organic carbon of I’s grade of source rock is higher, the kerogen type is good, the maturity reach over mature, and the horizon distribution is stable. The heat evolution history research of source rock indicates, the heat evolution level of its is lower in the period of the Paleozoic, and the oil-gas fromation phase by control of Jurassic stratum deposit thickness. The oil windows of C1 is upper Triassic-lower Jurassic, and natrual gas windows is lower Jurassic-upper Jurassic; The oil windows of S1 is lower Jurassic-middle Jurassic, and natural gas windows is middle Jurassic-Cretaceous; The oil windows of P1 is middle Jurassic-upper Jurassic, and natural gas windows is upper Jurassic-Cretaceous. This possesses important referennce to the research of source rock of high evolution area, and for oil-gas correlating, magrating and gathering of this area has established on the foundtaion.