准噶尔盆地东道海子凹陷油气成因及成藏期次分析

采集东道海子凹陷的烃源岩样品和油气样品,对样品进行有机碳、热解、饱和烃色谱及碳同位素等地球化学分析。在此基础上对东道海子凹陷烃源岩进行评价,研究认为石炭系烃源岩为一套高—过成熟的有机质类型差的中等烃源岩,二叠系烃源岩为一套成熟—高成熟的有机质类型好—较好烃源岩,侏罗系烃源岩为一套成熟的有机质类型差的中等烃源岩。该区油气成因复杂,通过油气的地球化学特征分析及油气源对比分析,结果表明既有来源于二叠系烃源岩的原油和天然气,也有来源于侏罗系的原油,还有来源于石炭系的天然气。油气成因的复杂导致油气成藏期次的多样,油气的成熟度及油气包裹体研究表明,既有一期成藏的油气,也有多期成藏的油气。

Analysis of hydrocarbon genesis and accumulation stage of Dongdaohaizi Sag in Junggar Basin

Geochemical analyses, such as total organic carbon(TOC), pyrolysis, gas chromatograms of saturated hydrocarbons and carbon isotopes, et al, were performed on the source rocks and hydrocarbon samples of Dongdaohaizi Sag.On that basis, the source rocks of Dongdaohaizi Sag were evaluated, the research suggests that the carboniferous hydrocarbon source rocks are in high-and post-mature with bad organic type and belong to middle grading, the Permian hydrocarbon source rocks are in mature to high mature with better to best organic type, Jurassic hydrocarbon source rocks are in mature with bad organic type and belong to middle grading.The hydrocarbon genesis of this region is complex. Through the comparative analysis of geochemistry characteristics and source of hydrocarbon, the results show that there are oil and gas coming from Permian hydrocarbon source rocks, oil from Jurassic and gas from carboniferous.