索尔库里盆地侏罗系烃源岩有机地球化学特征

在油气勘探中,烃源岩的研究占有重要组成部分。侏罗系烃源岩在索尔库里盆地主体部位广泛分布,面积3 875.7km~2,最大厚度300 m以上,分布在盆地中南部。对索尔库里盆地侏罗系烃源岩样品进行有机地球化学分析。通过研究生物标记化合物来分析有机质的类型、成熟度和沉积环境。结果表明:研究样品中饱和烃馏分含量较高,在33%~75%之间。烃源岩样品Pr/Ph分布范围在0.49~0.99之间,说明其具有还原沉积环境;三环萜烷/霍烷分布范围为0.27~2.64,r-/0.5C_(31)丰度平均值为0.34,具有明显的淡水沉积环境特征。样品规则甾烷均呈C_(27) C_(28) C_(29)的V字型分布,认为烃源岩以偏腐泥混合型母质为主。藿烷与甾烷的成熟度参数存在差异,说明了烃源岩可能受到微生物降解作用。因此,对索尔库里盆地侏罗系烃源岩的研究,为以后该区的油气勘探提供一定的科学依据。

The Organic Geochemical Characterization Of Jurassic source rocks in the Xorkol basin

In the oil and gas exploration in the source rocks occupy an important part of research. Jurassic source rocks are widely distributed in the body parts Xorkol basin, an area of 3875.7 square kilometers, more than the maximum thickness of 300m, located in south-central basin. This paper,through organic geochemical analyzes the hydrocarbon source rock samples in Jurassic basin of Xorkol and through the research of biomarker compounds to analyze organic matter type, maturity and sedimentary environment. The results shows that saturated hydrocarbon fractions content is higher in the research samples, in between 33% and 75%. Hydrocarbon source rock samples Pr / Ph distribution in the range of 0.49-0.99, indicating that it has sedimentary environment; Tricyclic terpane / hopane distribution in the range of 0.27-2.64, r-/0.5C31 average abundance is 0.34, has the characteristics of clear water sedimentary environment. Samples rule Sterane showed C27> C28