【作者】 刘卫；

【导师】 林承焰；

【作者基本信息】 中国石油大学 ， 地质资源与地质工程， 2010， 博士

【摘要】 论文以葡、敖油田葡I油组窄、薄砂岩油藏为例,综合运用油藏开发地质学理论和方法,利用地震、地质、测井、试油试采和开发动态等资料,通过深入研究具有不同开发特征的油藏类型、低级序断层、储层空间构型和窜流通道对剩余油的控制作用,从油藏、油层、单砂体、层内,分四个层次阐述剩余油的分布规律,揭示窄、薄砂岩油藏剩余油分布的新领域并提出相应的挖潜对策。论文所取得的主要成果有以下几方面:(1)根据窄、薄砂岩油藏的储层构型划分方案,开展了砂体空间构型研究。从垂向和平面两个方面逐步进行砂体解剖,垂向上利用泥质夹层、钙质夹层等六级结构面确定单期次的河道砂体;平面上则根据邻井砂体测井曲线形态及厚度的变化趋势等确定出单体河道边界,从而识别出复合河道砂体内的单河道砂体。葡、敖油田水下分流河道窄、薄砂岩油藏的单砂体的空间分布特征主要有4种,分别是:孤立式单成因砂体、对接式单成因砂体、切叠式单成因砂体和叠加式单成因砂体。对接式单成因砂体空间分布特征在窄、薄砂岩油藏中比较多见。(2)在储层构型研究的基础上,建立了基于单成因砂体的三维精细地质模型,通过对单成因砂体地质模型进行数值模拟,结合含油饱和度分布特征,从单成因砂体的结构尤其是夹层和单成因砂体拼合部位的渗流屏障等角度,探讨其对开发以及剩余油的形成与分布的影响,对接式单成因砂体的对接部位其剩余油较为富集。(3)遵循“关联度法定向,监测资料定层,动态分析定时”的原则可以在多油层合注合采条件下进行窜流通道的定量识别,关联度法可以在一个注采单元内圈定窜流通道的发育方向;根据高精度注入、产出剖面等测试资料识别窜流通道的发育层位;应用动态分析手段可以判断窜流通道的形成时间。取心井资料研究表明,窄薄砂岩油藏底部发育的窜流通道导致大量的无效水循环,顶部形成剩余油富集区。渗透率级差、注采强度、地下原油黏度越大,优势窜流通道越明显,受窜流通道屏蔽的剩余油富集程度越高。(4)通过高分辨率三维地震资料解释低级序断层,依据断点的平面分布情况,断层的性质、倾向、断距变化情况、断点位置及区域应力场的变化情况来进行断层组合。研究低级序断层特征、成因及对剩余油的控制作用。研究表明,低级序断层的侧向封闭能力较差,受其发育规模和封闭性的局限性,要与微构造和砂体共同作用才能对剩余油起到较好的遮挡作用。受断层分割形成的剩余油主要有5种类型,主要分布在断层的连接点附近,是断层控制的剩余油的主要富集区。(5)从开发角度对油藏类型进行定量划分的研究,建立了一套适应开发中后期油藏分类和储量动用状况的评价方法。运用油藏工程方法,结合油田的开发实际,以油藏类型为单位进行了储量动用状况的评价,发现剩余储量仍集中于构造油藏的一、二类油藏中,为井网的合理部署和剩余油的有效挖潜提供依据。(6)充分利用加密井取心资料、各种监测资料及数值模拟统计结果,从油藏、油层、单砂体、层内,四个层次阐述了窄、薄砂岩油藏剩余油的分布规律。研究表明:油藏规模的剩余储量仍集中于构造油藏的一、二类油藏中,对于不同圈闭成因的油藏来说,剩余油丰度的排列顺序为:构造油藏〉构造-岩性油藏〉岩性油藏;对于构造油藏的细分类别,剩余油丰度随着油藏所处构造位置的降低而降低。油层规模剩余油的形成主要受油层的平面和层间非均质影响,具体包括:沉积微相、储集层性质、砂体平面连通状况、微幅度构造、断层及层间干扰等开发条件的影响。(7)在储层精细结构解剖、优势窜流通道识别、数值模拟、低级序断层研究、油藏综合评价等动静态结合研究基础上,提出了葡、敖油田窄、薄砂岩油藏剩余油分布的新领域:①由于单砂体的空间分布结构与注采井网匹配性较差所导致的注入水无法驱到的剩余油;②受优势窜流通道屏蔽的剩余油;③低级序断层、微构造和砂体共同遮挡形成的剩余油。(8)基于葡、敖油田不同类型的剩余油形成方式及分布特点,提出了相应的挖潜对策。部分措施已经付诸实施,并取得了良好的挖潜效果,有效指导了油藏的高效开发。研究不仅对葡、敖油田具有重要意义,而且对其它类似油田也具有一定借鉴价值。更多还原

【Abstract】 Taking the narrow and thin sandstone reservoir of pu I oil group in Putaohua and Aobaota oilfield as a case,with the data of seismic, geology, well logging, well test and early production test, the paper deeply studied the controlling function of the reservoir type, the low-grade fault, reservoir architecture and the channeling path on the remaining oil under the theory and method of reservoir geology, described the law of the distribution of remaining oil on four scales: reservoir, layer, single sand body, and internal layer, finally revealed new area of remaining oil in the narrow and thin sandstone reservoirs and proposed the corresponding potential exploitation measures.The paper achieved some innovational scientific payoffs. Main achievements of the study are summarized as following:(1) According to the classification scheme of the narrow and thin sandstone reservoir, the paper carried out the reservoir architecture study. The sand body was analyzed from both vertical and horizontal aspect to identify the channel boundary, with the six class structural surface,such as muddy intercalation, calcareous intercalation in the vertical; based on the form of logs and the changes of the thickness of sandbody in the adjacent wells in the horizontal, thus the single sand body was recognized in the composite channels. The architectures of the single channel of the Putaohua and Aobaota oilfield are mainly four kinds: isolated monogene sand body, butt jointed monogene sand body, cutting piled monogene sand body and superposed monogene sand body, among them, the butt jointed is common in the narrow and thin sand body reservoir.(2) On the basis of the reservoir architecture study, a 3D geological model was set up. Through numerical simulation, combining with the oil saturation distribution, the paper discussed the influence of the architecture, especially the intercalated layer, and the flow barrier in the jointed place on the exploitation and the remaining oil distribution. The butt jointed monogene sand body has a rich remaining oil accumulation. (3) Following the rule "degree of association to decide direction, monitoring data to decide layer, dynamic analysis to decide time", the channeling paths can be identified under the condition of commingled water injection and oil extraction. Degree of association can block out the development direction of the channeling paths; based on the high accuracy injection and production data can identify the layer of the channeling paths; the dynamic data can be used to judge the time the channel paths formed. The study of the cored well shows that the development of channeling paths in the narrow and thin sandstone reservoir can hinder the formation of remaining oil.(4) With the low-grade faults interpreted by the high-resolution 3D seismic data, the faults were assemblaged based on the changes of the plane distribution of the breakpoints, the fault character, dip direction, fault displacement, breakpoint location and regional of stress. The paper studied how the characteristics of the low-grade fault, the genesis and the fault lateral sealing control the remaining oil distribution. The study shows that the low-grade fault, under the limitation of its scale and sealing property, can play better on barring oil migrating with the coordination of micro-relief structure and sand body. The remaining oil caused by the fault cut is mainly five kinds, and the enriched area distributed near the fault joint.(5) Through the quantitative research on the reservoir type from the development point of view, a set of evaluation system suiting for reservoir classification and producing reserves in middle and late development stage was established. Using the reservoir engineering method, combined with the development reality, the evaluation was carried out, which provided more effective evidence to dispose the well pattern arrangement and exploit the remaining oil.(6) Making full use of the data of cored well, monitoring data and numerical simulation results, the paper described the law of the distribution of remaining oil from four different levels: reservoir, layer, single sand body and internal layer. The study indicates that the remaining reserve of reservoir size is still concentrated in the first and second type reservoir, both structural reservoirs. To different trap genesis, the abundance of remaining oil is structural reservoir> structural - lithologic reservoir> lithologic reservoir. Also, the abundance reduces as the structural location becomes lower. The formation of remaining reserve of oil layer size is affected by the plane and interplayer heterogeneity, including sedimentary face, reservoir property, the plane connectivity of the sand body, micro-relief structure, fault and inter zone interferences, etc.(7) Based on the research of the reservoir architecture analysis, the identification of channeling paths, numerical simulation, study of the low-grade fault and comprehensive evaluation of the reservoir, a frontier of remaining oil distribution is proposed: firstly, the remaining oil caused by the sand body architecture with improper injection patterns; secondly, the remaining oil hindered by the channeling paths; thirdly, the remaining oil controlled intergratedly by the low-grade fault, micro-relief structure and sand body.(8)The strategies of potential tapping have been proposed according to the formation and distribution characteristics of remaining oil, and some of which succeeded with better effects. This research is of great significance not only in the peripheral oilfields in Daqing but also in other similar oilfields.更多还原