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对27件塔里木盆地台盆区寒武系烃源岩样品进行了有机碳测定、饱和烃色谱质谱、芳烃色谱质谱及馏分稳定碳同位素等分析以获取其生烃潜力与地球化学特征信息。结果显示烃源岩TOC值较高(0.5%~8.39%),属于较好—很好的烃源岩范畴。下寒武统烃源岩最好,其次为中寒武统。分子标志物分析表明烃源岩以菌藻类或低等水生生物来源为主。低姥植比、高硫芴含量表明沉积环境还原性较强。高伽马蜡烷含量指示了水体分层环境。三环萜烷发育完整,C_(21)三环萜烷/C_(23)三环萜烷大于1。甾烷相对含量高,C_(28)/(C_(27)+C_(28)+C_(29))规则甾烷≥25%。寒武系烃源岩C_(26)及C_(27)三芳甾烷发育,三芳甲藻甾烷含量丰富。烃源岩可溶有机组分稳定碳同位素组成整体偏重,一般重于-31‰。柯坪隆起下寒武统肖尔布拉克剖面泥岩各指标均不同于其余寒武系烃源岩样品,暗示了不同的生源构成。
Organic carbon determination, saturated hydrocarbon chromatographic mass spectrum, aromatic hydrocarbon chromatographic mass spectrum and stable carbon isotope analysis of 27 Cambrian hydrocarbon source rocks in the Tarim Basin, Tarim Basin, were carried out to obtain information on hydrocarbon generation potential and geochemical characteristics. The results show that the TOC values of source rocks are high (0.5% ~ 8.39%) and belong to the better source rocks. The Lower Cambrian source rocks are the best, followed by the middle Cambrian. Molecular marker analysis shows that the source rock is dominated by bacteria and algae or lower aquatic organisms. Low basking than the high sulfur fluorene content shows strong reduction of sedimentary environment. High gamma-gamma-alkanes indicate the stratification of the water body. Tricyclic terpanes are well developed. C_ (21) tricyclic terpanes / C_ (23) tricyclic terpanes are more than one. The relative content of sterane is high, and the content of C 28 C 27 C + 28 + C 29 is more than 25%. The Cambrian source rocks C_ (26) and C_ (27) triflate have developed, and the content of trifiuoroosane is rich. The stable carbon isotope composition of soluble organic components of source rocks is generally heavier, generally heavier than -31 ‰. The indicators of mudstone in the Lower Cambrian Shoballark profile of the Keping Uplift are all different from the other Cambrian source rock samples, suggesting different source composition.