准噶尔盆地永进地区油源研究

Study on the Source of Oils in Yongjin Area,Junggar Basin

在分析和归纳可能烃源岩的有机地化特征并对原油样品进行分析测试的基础上,主要运用生物标志物和稳定碳同位素指标或参数,首次对准噶尔盆地永进地区原油的来源进行了系统研究,认为中二叠统和中下侏罗统烃源岩是为该地区提供油源的主要烃源岩,其次为下二叠统烃源岩,并可能有白垩系烃源岩的贡献。其中,中侏罗统西山窑组煤层之上及大部分白垩系储层中的正常原油主要来自中二叠统烃源岩;煤层之下及下侏罗统三工河组储层中的正常原油主要来自中下侏罗统烃源岩;在现今油藏中所占比例较小并已发生强烈生物降解的原油来自下二叠统烃源岩;永6井白垩系储层中的原油可能来自下白垩统烃源岩,但该套烃源岩的供烃规模可能较小。

Based on the analysis and induction of the organic geochemical characteristics of the potential source rocks as well as the test results of the oil samples, the source of oils in Yongjin area was first systematically studied mainly using the indications of biomarker and stable carbon isotope. It is considered that the oils in Yongjin area were mainly generated from the mid-Permian and mid-to-lower-Jurassic source rocks, partly from the lower-Permian source rock, and potentially from the Cretaceous source rock. In detail, the normal oils in the container beds of mid-Jurassicg Xis- hanyao Formation which are above the coal layer, as well as in the most Cretaceous container beds, mainly came from the mid-Permian source rock; the normal oils in the container beds of mid-Jurassic＇s Xishanyao Formation which are beneath the coal layer, as well as in the container beds of lower Jurassic Sangonghe Formation, mainly came from the mid-to-lower Jurassic source rock; the oils, which account for a small proportion in the pool and experienced serious biodegradation, came from the lower-Permian source rock ; and the oil in the Cretaceous container rock of Well Yong 6 probably came from the lower-Cretaceous source rock, but the hydrocarbon-supplying power of this source rock may be weak.