轮南、塔河油田稠油油源对比

Oil and source correlation in Lunnan and Tahe heavy oil fields

马安来 张水昌 张大江 金之钧

Ma Anlai Zhang Shuichang Zhang Dajiang Jin Zhijun

运用GC,GC-MS,GC-MS-MS、配比实验、沥青质钌离子催化氧化技术,研究了塔里木盆地轮南、塔河稠油油源。轮南、塔河油田稠油中含有25降藿烷,但正构烷烃分布完整,色谱基线呈不同程度抬升,油藏经历了两期成藏过程。稠油具有三环萜烷含量高、C四环萜烷含量低、伽马蜡烷含量低、C甾烷含量低、甲藻甾烷及三芳甲藻甾烷含量低、4甲基24乙基胆甾烷及其芳构化甾烷含量低、24降甾烷含量低的特点。油源对比表明轮南、塔河稠油来源中、上奥陶统烃源岩。配比实验表明,原油中若混入了25%寒武系生源的TD2井原油,混源油也会呈现寒武系生源的特点,表明寒武系烃源岩生成的原油并未大规模混入到轮南、塔河油藏中。轮南、塔河稠油沥青质钌离子氧化降解产物在一元酸及甾烷酸、4甲基甾烷酸的分布与TD2井稠油明显不同,进一步证明中、上奥陶统烃源岩可能为轮南、塔河稠油的主力源岩。

Several technologies, including GC,GC-MS,GC-MS-MS,match experiment and ruthenium ion catalytic oxidation of asphaltenes,are used to study the sources of heavy oil in Lunnan and Tahe oilfields, Tarim basin. The heavy oil in Lunnan and Tahe oilfields contain 25-norhopane, while the distribution of normal paraffin hydrocarbons is complete and chromatographic base lines are uplifted in varying degrees,showing that the accumulations have been formed in two stages. The heavy oil are characterized by high content of tricyclic terpane, low content of C tetracyclic terpane, gammacerane, C sterane, triaromatic sterane, 4-methyl cholestane-24-ethyl cholestane, aromized sterane,and 24-norsterane. Oil and source rock correlation indicates that the oil in Lunnan and Tahe oilfields come from the source rocks in Middle and Upper Ordovician. Match experiments show that the oil would have also the characteristics of Cambrian source rock if it is mixed with 25% of TD2well's oil generated from Cambrian source rock,indicating that the hydrocarbons generated from Cambrian source rocks have not extensively migrated into Lunan and Tahe reservoirs. Ruthenium ion catalytic oxidation of asphaltenes further verifies that the source rocks in Middle and Upper Ordovician are the main source rocks of heavy oil in Lunnan and Tahe oilfields.

10.11743/ogg20040106