对芒罕超克地区阿木山组(C2P1a)岩性组合与沉积相纵向发育特征研究,结合区域沉积相展布分析,认为阿木山组沉积期为巴丹吉林海相裂谷盆地发育的鼎盛时期,沉积了一套厚度巨大的浅海陆棚相泥页岩,是区内烃源岩发育的主要层段.以TOC≥0.3%为下限,折算烃源岩厚度121.39m.其中,TOC含量中等-较高的烃源岩厚度达89.11m,占烃源岩分布层段厚度的58.9%;干酪根C同位素、甾烷C27与C29相对含量、饱和烃特征等地球化学指标研究表明,干酪根类型以Ⅱ型为主;姥鲛烷(Pr)/植烷(Pb)所反映的原始沉积环境表明,有机质沉积环境主要为还原环境,对有机质保存有利;镜质组反射率、最大热解温度和伊利石结晶度分析表明,烃源岩演化进入过成熟阶段,主要受构造动力作用和华力西晚期、印支期岩浆热接触作用的影响,不存在区域变质,不影响区域上阿木山组作为重要的烃源岩层段.%Based on a study of the lithologic association, vertical characteristics of sedimentary facies and regional sedimentary distribution of Amushan Formation in Manghanchaoke region, the authors hold that the flourishing period of Badanjilin marine rift basin was the sedimentary period of Amushan Formation, during which the shallow marine shelf facies mud shale of huge sedimentary thickness was deposited, which constitutes the main layer section of source rocks in this region. With TOC ≥0.3％ as the lower limit, the converted thickness of the source rock is 121.39m, in which the thickness of middle to higher organic carbon is 89.11m,possessing 58.9％ of the thickness of the hydrocarbon source rock layer. A study of geochemical indexes of kerogen carbon isotopes, the relative content of C27 & C29 sterane and saturation hydrocarbon characteristics shows that the main kerogen type is Ⅱ type. An analysis of original sedimentary environment with Pr/Ph shows that the main sedimentary environment was a reducing environment, which was beneficial for the preservation of organic matter. And the characteristics of vitrinite reflectance solid, maximum pyrolytic temperature and illite crystallinity show that the source rock owed its conversion into higly-mature to over-mature stage and mainly over-mature stage to the influence of tectonic dynamic activity and magma metamorphism of late Variscan and Indo-Chinese epoch. There has been no regional metamorphism, so Amushan Formation is the main source rock layer section in this region.
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