环玛湖凹陷三叠系百口泉组油藏混源特征及成藏机理

发布时间：2018-03-18 12:34

本文选题：混源油　切入点：三环萜　出处：《中国石油大学(北京)》2016年博士论文　论文类型：学位论文

【摘要】：叠合盆地发育多套烃源岩,油气混源现象普遍,搞清源岩对混源油贡献大小及混源油如何成藏对于预测油气分布具有重要意义。针对准噶尔盆地玛湖凹陷百口泉组油藏原油混源现象普遍的特征,开展了烃源岩生烃特征、原油类型划分、油源对比、油气运移及聚集机制研究,阐明了百口泉油藏的成藏模式,确定了百口泉组原油混源的主控因素。二叠系源岩中,风城组烃源岩有机质丰度高、类型好,是本区主力源岩,其三环萜烷C20、C21和C23呈典型的“上升型”分布,为进一步探讨其生烃特征差异,将其细分为泥岩类及碳酸盐岩类两类源岩,泥岩类三环萜中更富集C25三环萜烷;乌尔禾组烃源岩其次,三环萜主要呈“下降型”分布,具有一定的生油能力;佳木河组烃源岩演化程度高,有机质类型以III型为主,难作为有效油源岩;有机岩石学及热模拟实验证实,源岩三环萜的分布主要受控于母质类型与沉积环境,成熟度会造成三环萜总体增加,但不影响其分布型式,排烃作用对其影响较小。针对百口泉组原油成熟度较高、三环萜烷含量丰富的特征,综合生标、碳同位素、微量元素等指标,将其分为3大类5亚类并进行油源对比:A1类原油来自风城组碳酸盐岩,A2类来自风城组泥岩;B类来自乌尔禾组泥岩;C1类为风城组碳酸盐岩与乌尔禾组泥岩混源成因,C2类为风城组泥岩与乌尔禾组泥岩混源成因;对于混源油混合比例,采用物质平衡法反演计算与端元油混合配比实验正演相结合,计算了不同油藏原油样品的混源比例:断裂带油藏混源油的油源主要为风城组,乌尔禾组贡献大部分低于30%;斜坡带油藏混源原油不同样品比例变化较大;深洼带原油主要油源为乌尔禾组泥岩,风城组来源原油混入比例基本低于20%。利用包裹体荧光及FTIR参数限定了原油混合类型为多期混源,包裹体均一温度确认百口泉组混源油藏一般发育两期包裹体。研究了不同岩相及成熟度对含氮化合物的影响,利用优选运移参数研究了运移方式:原油在深洼部位侧向运移为主,断裂带以垂向运移为主,斜坡带兼具两种运移方式。在此基础上建立了成藏模式:断裂带双源断层-不整合输导两期成藏,斜坡带双源断层-近源砂体输导成藏和深洼带单源砂体输导一期成藏;阐明了原油混源的主控因素:源岩时空展布控制原油混源类型及其分布,源岩相类型、成熟度及早期残留沥青导致原油地球化学特征的差异,输导体系的配置关系决定不同油藏混源过程。
[Abstract]:There are many sets of hydrocarbon source rocks developed in the superimposed basin, and the phenomenon of oil and gas mixing is common. The contribution of Qingyuan rock to the mixed source oil and how the mixed source oil is formed is of great significance for predicting the distribution of oil and gas. In view of the common phenomenon of mixed source of oil in Baikouquan formation reservoir in Mahu depression of Junggar Basin, the hydrocarbon generation characteristics of source rock are carried out. The classification of crude oil types, oil source correlation, migration and accumulation mechanism of oil and gas are studied. The reservoir forming model of Baikouquan reservoir is clarified, and the main controlling factors of mixed source of crude oil in Baikouquan formation are determined. In the Permian source rocks, the organic matter abundance of source rock in Fengcheng formation is high. It is the main source rock in this area, and its tricyclic terpene C _ (20) C _ (21) and C _ (23) have typical "ascending" distribution. In order to further study the difference of its hydrocarbon generation characteristics, it is subdivided into two types of source rocks: mudstone and carbonate rock. In mudstone, tricyclic terpenes are more enriched in C25 tricyclic terpenes, the source rocks of Wuerhe formation are next, tricyclic terpenes are mainly of "descending type" distribution and have certain oil generation ability, the evolution degree of source rocks in Jiamuhe formation is high, and the type of organic matter is mainly III type. The distribution of tricyclic terpenes in the source rocks is mainly controlled by the parent material type and sedimentary environment, and maturity will cause the total increase of tricyclic terpenes, but do not affect their distribution patterns, the organic petrology and thermal simulation experiments show that the distribution of tricyclic terpenes in the source rocks is mainly controlled by the parent material type and sedimentary environment. In view of the characteristics of high maturity and rich trichloroterpene content in Baikouquan formation crude oil, comprehensive genetic criteria, carbon isotopes, trace elements, and so on, have little effect on hydrocarbon expulsion. It is divided into 3 categories and 5 subclasses, and the oil source correlation is carried out. The crude oil of type A1 comes from carbonate rock of Fengcheng formation and type A 2 from mudstone of Fengcheng formation. Type B comes from mudstone of Wuerhe formation. Type C1 is the origin of mixed source of carbonate rock of Fengcheng formation and mudstone of Wuerhe formation. The origin of C _ 2 is mixed source of mudstone of Fengcheng formation and Wuerhe formation; The mixing ratio of mixed source oil is calculated by combining the inverse calculation of material balance method with the experiment of mixing ratio of end component oil, and the proportion of mixed source of crude oil samples in different reservoirs is calculated: the oil source of mixed source oil in fault zone reservoir is mainly Fengcheng formation, the main source of mixed source oil in fault zone reservoir is Fengcheng formation. The contribution of Wuerhe formation is mostly less than 30%; the proportion of mixed source crude oil varies greatly in slope zone reservoir; the main oil source in deep depression zone is mudstone of Wuerhe formation. The mixing ratio of crude oil from Fengcheng formation is lower than 20%. By using the inclusion fluorescence and FTIR parameters, the mixing type of crude oil is defined as multi-period mixed source. The homogenization temperature of inclusions confirmed that the mixed source reservoirs of Baikouquan formation generally developed two stages of inclusions. The effects of different lithofacies and maturity on nitrogen-bearing compounds were studied. Based on the optimal migration parameters, the migration patterns are studied: the lateral migration of crude oil in deep lying areas is dominant, and the vertical migration of fault zones is dominant. There are two migration modes in the slope zone. On the basis of this, the reservoir forming model is established: dual source fault-unconformable reservoir formation in fault zone, dual source fault-near-source sand body transportation and reservoir formation in slope zone and single source sand body transport in deep depression zone. The main controlling factors of mixed source of crude oil are expounded, such as the distribution of source rocks, the type and distribution of source rocks, the type of source rocks, the maturity of source rocks, and the difference of geochemical characteristics of crude oil caused by residual bitumen in the early stage. The distribution of the transport system determines the mixing process of different reservoirs.
【学位授予单位】：中国石油大学(北京)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：P618.13

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