【作者】 郭春清；

【导师】 沈忠民； 张林晔；

【作者基本信息】 成都理工大学 ， 矿产普查与勘探， 2005， 硕士

【摘要】 本文应用油气地球化学分析与评价方法,系统研究了准噶尔盆地四棵树凹陷的生油潜力并指明了有利勘探区域,其目的是为准噶尔盆地南缘西段成藏条件研究及勘探目标优选提供地球化学依据,并为中石化在准噶尔盆地西部探区的勘探决策提供理论支持。 本文的主要研究成果为:1) 四棵树凹陷中下侏罗统烃源岩生源以陆源高等植物为主,沉积于弱氧化～弱还原的淡水环境,有机质类型和保存条件较差;下第三系安集海河组烃源岩生源以低等水生生物为主,沉积于较为咸化的还原环境,有机质类型和保存条件好;泥质烃源岩普遍具有有机质丰度和热演化程度低的特点,生烃指标较差,而中下侏罗统碳质泥岩和煤的生烃潜量指标总体上达到了好～极好烃源岩的级别。2) 热模拟试验表明,八道湾组泥质烃源岩生气能力强,生油能力差;热模拟产物的甾、萜烷特征表明侏罗系湖相烃源岩和煤系烃源岩在地化特征上存在较大的差异。3) 中下侏罗统烃源岩的生烃门限深度为5000m,下第三系安集海河组烃源岩约为5300m。4) 油源研究表明,霍尔果斯原油来自下第三系安集海河组烃源岩,卡6井白垩系原油来自中下侏罗统煤系烃源岩,独山子原油和卡6井下第三系原油为来自二者的混源油;西5井和石油沟原油来自盆地南缘的二叠系烃源岩。5) 四棵树凹陷常规石油资源量约为5.3亿吨。6) 热模拟试验表明中侏罗统煤和碳质泥岩具备较高的液态烃产率,有机相研究也表明四棵树凹陷煤系地层发育有生油能力较强的流水沼泽有机相和森林沼泽有机相。7) 固2井上第三系烃源岩具备生成低熟油的有利地球化学条件。 通过研究,得出如下主要结论:1) 中下侏罗统和下第三系安集海河组烃源岩是四棵树凹陷的有效烃源岩,而三叠系和上第三系烃源岩的有效性尚待证实。2) 四棵树凹陷中下侏罗统泥质烃源岩虽然生油指标一般,但由于分布范围广、厚度大,总体上仍具备较高的生油潜力;下第三系安集海河组烃源岩在局部成熟区具备较高的生油潜力。3) 常规石油资源主要集中在凹陷东部地区,相应的勘探要紧紧围绕该地区的成熟烃源岩体展开。4) 四棵树凹陷有巨大的煤成油勘探潜力,其资源量主要分布在四参1井以东地区。5) 中下侏罗统湖相烃源岩地化特征研究、混源油气精细油源研究是四棵树凹陷下一步地化研究工作的重点。更多还原

【Abstract】 In this thesis, by means of geochemical analysis and assessment, the oil-generating potential was systematically studied and the favorable places for prospecting were showed in Sikeshu Sag, Junggar Basin. The purpose of this is to establish the geochemical basis for the study of reservoir-forming conditions and the selection of exploration targets in the west part of the southern rim of Junggar Basin, and also to provide the theoretical support for exploration decision in Sinopec.’s west exploration area of Junggar Basin.The main research findings of this thesis are as follows: 1) In Sikeshu Sag, the middle-lower Jurassic source rocks are characterized by the major original organism input of terrestrial higher plants, the sedimentary environment of weak oxidation to weak disoxidation in fresh water, and the poorer organic types and preservation condition. By contrast, the source rocks of Anjihaihe formation in Palaeogene are characterized by lower hydrobios input, disoxidation in relatively salty water environment, and the favorable organic types and preservation condition. The muddy source rocks in this area commonly have lower organic matter abundance and lower thermal evolution degree leading to the weaker hydrocarbon-generating ability, whereas the middle-lower Jurassic carbargilite and coal generally reach to good to first-class rank in source rock evaluation. 2) Thermal simulating test showed that the source rock of Badaowan formation has stronger gas-generating ability versus weaker oil-generating ability, and the characteristics of sterane and terpane from thermal simulation products indicated that there are significant differences in geochemical feature between the source rocks of Jurassic lacustrine facies and coal measures. 3) The depth of hydrocarbon- generating threshold is 5000m for Jurassic source rocks and about 5300m for the source rocks of Anjihaihe formatin in Palaeogene. 4) The study of oil source made clear that Huoerguosi oil was from the source rocks of Anjihaihe formation in Palaeogene, Cretaceous oil from Ka 6 well was from the source rocks of Jurassic coal measure, Dushanzi oil and Palaeogene oil from Ka 6 well are the mixture from the two source rocks, and oils from Xi 5 well and更多还原