松辽盆地梨树断陷下白垩统营城组烃源岩地球化学特征及油源对比

发布时间：2018-02-28 06:38

本文关键词： 梨树断陷烃源岩地球化学特征原油生物标志化合物油源对比　出处：《长江大学》2017年硕士论文　论文类型：学位论文

【摘要】：梨树断陷位于松南断陷群的南部,该盆地的烃源岩发育良好,存在大量的石油天然气资源。本文使用常规地球化学实验分析方法和生物标志化合物分析方法,对松辽盆地梨树断陷下白垩统营城组的烃源岩和原油进行了系统的研究,结合前人的研究成果,来确定梨树断陷烃源岩的地球化学特征,划分主力烃源岩,进行油源对比,为梨树断陷进一步的勘探开发给出一份理论上的依据。1、梨树断陷营城组烃源岩以中等-好烃源岩为主,还发育有部分优质烃源岩。其中,优质烃源岩主要分布在盆地西南部深凹带,在双龙次凹和后五家户—小城子一带发育有好烃源岩,八屋地区大部分为中等-好烃源岩,北部斜坡部分地区分布有中等-好烃源岩,秦家屯和皮家地区烃源岩发育比较差。烃源岩有机质类型主要为Ⅱ型和Ⅲ型。烃源岩有机质热演化程度大多处于成熟阶段,部分地区处于高成熟阶段。综合以上,梨树断陷营城组主力烃源岩分布在后五家户—小城子西边的深凹带,其次双龙次凹和八屋地区的营城组烃源岩也是重要的油气来源。2、断陷盆地由中部至周边,水体盐度不断降低,还原性不断变弱。梨树断陷营城组烃源岩有机质有双重来源,包括陆源高等植物和低等水生生物,其中陆源高等植物贡献比较大,是典型的发育在断陷湖盆的烃源岩。多数烃源岩的沉积环境为深湖-半深湖相,具有较深的水体,比较强的还原性,并且藻类和高等植物是有机质输入的主体;部分为浅湖相(八屋地区SN65井和SN118井),具有较浅的水体,比较弱的还原性,烃源岩有机质输入以高等植物为主;沉积环境为滨湖-河流相的烃源岩分布在双龙次凹,这种沉积环境水体较浅,还原性较弱,烃源岩有机质输入以高等植物为主。3、梨树断陷营城组原油具有湖相油的特点,形成于偏还原性的微咸水-咸水沉积环境,有机质来源主要为陆源高等植物,此外还包括藻类和细菌等低等生物。正构烷烃C10~C38分布完整,绝大多数为单峰型,主峰碳主要为C21。各油田的原油的正构烷烃轻重比nC21-/nC22+、CPI和OEP值均变化不大。绝大多数原油三环萜烷系列化合物呈主峰为C23的正态分布,原油样品C26以后的长链三环萜烷含量比较高,呈现出“翘尾巴”的特征,梨树断陷各区块营城组原油都具有比较高含量的伽马蜡烷,原油伽马蜡烷/C30藿烷比值分布在0.33~1.10的范围内。原油绝大多数处于成熟阶段,且八屋油田BK60区块和SN54区块的原油成熟度较其他地区高。4、按照原油的地球化学特征,把原油分为了以下三类:Ⅰ类原油C24四环二萜/C26三环萜烷的值为0.23~0.65,三环萜烷/五环三萜的值为0.07~0.43,Ts≤Tm,伽马蜡烷/C30藿烷的值是0.16~0.42;Ⅱ类原油C24四环二萜/C26三环萜烷的值是0.11~0.28,三环萜烷/五环三萜的值是0.47~4.06,TsTm,伽马蜡烷/C30藿烷的值是0.42~1.10;Ⅲ类原油的地化特征处在上述两者之间,是由二者混合生成的。5、梨树断陷营城组Ⅰ类原油与营城组烃源岩具有相似的甾萜烷组成特征,C28三环萜烷和C29三环萜烷丰度都比较低,Ts与Tm丰度差不多,C29Ts和C30重排藿烷丰度也比较低,说明Ⅰ类原油来源于营城组烃源岩;而Ⅱ类原油和营城组烃源岩差异明显,营城组烃源岩不能作为Ⅱ类原油的来源,Ⅱ类原油来源于沙河子组烃源岩;Ⅲ类原油是由Ⅰ类原油和Ⅱ类原油混合而成,属于营城组和沙河子组烃源岩联合供给烃类。
[Abstract]:Located in the southern Songliao Basin faulted Southern Lishu fault depression basin, the hydrocarbon source rocks is good, there are a large number of oil and gas resources. The conventional geochemical methods and experimental analysis of biomarker compounds analysis using this method, in the Lishu rift in the lower Cretaceous Yingcheng formation hydrocarbon source rocks and crude oil were system research, combined with previous research results, to determine the geochemical characteristics of source rocks in Lishu fault depression, division of main source rocks, oil source correlation, for the exploration and development of Lishu fault depression is given to a theoretical basis for.1, with moderate good source rocks in the main hydrocarbon source of Yingcheng Group rocks in pear tree, also developed some high-quality hydrocarbon source rocks. The hydrocarbon source rocks are mainly distributed in the southwest Basin deep sag, sag and Ssangyong after five households - Xiaochengzi area developed good source rocks, eight houses mostly moderate to good hydrocarbon The source rocks, the northern slope of the geographical distribution of some moderate good source rock, Qinjiatun and skin source rocks are relatively poor. The development of regional source rock organic matter types are mainly type. The organic matter of source rock thermal evolution degree is mostly at the mature stage, some areas in high mature stage. In the above, the main hydrocarbon source rocks of Yingcheng Group distributed in five households after the deep concave Xiaochengzi West Zone of Lishu fault source of oil and gas.2, Yingcheng Formation source rocks second and eight house area Shuanglong sag is also important, faulted basin from the middle to the surrounding water salinity decreased continuously, also primary weakening. Lishu fault depression of organic matter in source rocks of Yingcheng Formation of dual sources, including terrestrial higher plants and low aquatic organisms, including terrestrial plants is relatively large contribution, is a typical development in rift basin source rocks. The sedimentary environment of source rocks is the most deep lake deep lake half Phase, deep water, reducing the relatively strong, and algae and higher plants are the main organic matter input; part of shallow lake facies (eight house area SN65 and SN118 wells), with shallow water, reducing the weak, source rock organic matter input to higher plants. Binhu; sedimentary environment is fluvial facies hydrocarbon source rock distribution in Shuanglong sag. The sedimentary environment with shallow water, reducing weak source rock organic matter input to higher plants.3 characters in Yingcheng Formation of lacustrine oil oil has Lishu fault, formed in the partial reduction of brackish water brackish water sedimentary environment, source of organic matter was mainly terrigenous higher plants, in addition to algae and bacteria and other biological n-alkanes. The distribution of C10~C38 integrity, the vast majority of unimodal, n-alkanes weight ratio nC21-/ nC22+ peak carbon mainly for the oil field C21. crude oil, CPI and OEP values are variable Little. Most of the crude oil of tricyclic terpane compounds showed a peak to the normal distribution of C23, long chain oil samples after C26 tricyclic terpane content is relatively high, showing the characteristics of "qiaoyiba" camp, gammacerane city group has a relatively high content of crude oil of each block of Lishu fault depression, crude gamma wax alkane /C30 hopane ratio distribution in the range of 0.33~1.10. Most of the crude oil in the mature stage, and the eight House in BK60 block and SN54 block the maturity of crude oil is higher than other regions of.4, according to the geochemical characteristics of crude oil, crude oil is divided into the following three types: the first type of crude oil C24 two tetracyclic triterpenoid /C26 tricyclene cetane value is 0.23~0.65, tricyclic terpane / three pentacyclic terpene value is 0.07~0.43, Ts = Tm, gammacerane /C30 hopane value is 0.16~0.42; class II oil C24 two tetracyclic triterpenoid /C26 tricyclic terpane value is 0.11~0.28, tricyclic terpane / five three terpene value 0.47~4.06, TsTm, /C30 and gammacerane hopanoic value is 0.42~1.10; the characteristics of class III oil in between the two generation, is mixed by.5, has the similar characteristics of steranes and terpanes of Yingcheng Formation of crude oil and source rocks in Yingcheng Formation of Lishu fault, C28 tricyclene alkyl and C29 tricyclic terpane abundances are relatively low, and the Ts C29Ts and C30 Tm abundance almost Diahopane abundance is relatively low, indicating type crude oil originates from the source rocks of Yingcheng Formation; type II crude oil and source rocks of Yingcheng Group is significantly different, Yingcheng Formation source rocks cannot be used as a source class II class II of crude oil, crude oil originates from the hydrocarbon source rock of Shahe sub group; class III oil is composed of class I and class II mixed crude oil and crude oil, which belongs to the Yingcheng Group and Shahe sub group of source rock joint supply of hydrocarbons.

【学位授予单位】：长江大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P618.13

【相似文献】