【作者】 王明学；

【导师】 周海民； 刘永建；

【作者基本信息】 东北石油大学 ， 油气田开发工程， 2011， 博士

【摘要】 大庆西部稠油油藏具有资源潜力大,分布面积广的特点,主要聚集在松辽盆地西部斜坡带边缘,已提交各类储量4372.3×104t,是大庆油田保持稳产高产的重要区块,勘探前景令人鼓舞。本文是基于稠油油藏在开发中所面临的实际问题,在总结前人已有成果的基础上,将油气田开发地质,油藏工程原理,物理模拟实验和油藏数值模拟有机结合,对大庆西部稠油进行潜力评价及开发方式优化,为大庆油田高效开发提供一些理论依据和可用技术,主要完成了以下研究工作：从区域地质概况和形成油气藏动静态因素评价入手,对油气水分布、稠油油源、运移通道和成藏模式进行分析。不整合面是油气横向运移的主要通道,虽然断层不是油气运移的主要通道,但其可起到连通砂体的作用,从而成为油气侧向运移的通道,油气在遇到有利聚集条件时聚留其中,从而形成了他拉红、平洋、阿拉新、二站、江桥和富拉尔基等有利含油气区块。深入分析了各油层油气水分布规律,为合理制定开发方案提供了科学依据。通过分析西部斜坡区稠油生烃条件和组分对比,指明西部斜坡区的大部分原油不是自生的,而是经过长途运移来的。构造的缓坡带对油气聚集具有控制作用,构造和岩性以及断层的匹配关系等共同控制油气成藏。因此大庆西部稠油成藏的主控因素为：不整合面运移,断层疏导,缓坡控油,复合控藏。西部斜坡区油藏评价难度大,主要表现在两个方面：在储层展布上,表现为储层横向变化大,砂体发育不连续,目的层单一；在油藏类型上,表现为构造岩性油藏和岩性油藏增多。通过解剖失利井,综合沉积、构造和成藏特征,提出了大庆西部斜坡区主要目的层萨尔图油层和高台子油层有利区目标建议。通过对失利井和高产井地质分析,认为只有构造、砂体、储层有机匹配才能形成有利的油气藏。形成了一套大庆西部空白区、扩边区及剩余油挖潜区(加密区)分析找油新方法。应用地震解释、储层预测、沉积相研究和精细砂体解剖等多种技术,在成藏主控因素的指导下,开展分区块、分油藏的逐级筛选,综合考虑构造、储层、流体分布等多种成藏控制因素,评价大庆西部稠油资源潜力,初步估算了阿拉新地区,二站地区,平洋地区以及江桥地区的地质储量。选取大庆西部稠油区块的天然岩心,进行室内实验,对不同的开发方式进行优化。分别开展了热水驱、蒸汽驱、化学驱、泡沫驱、烟道气驱、微生物驱替实验。对每种驱替方式的含水率,采收率,注入pv,注入时机,注入浓度等参数进行整体对比分析,优化不同的驱替方式。实验结果表明：蒸汽驱和热水驱的最终采收率最高,可达50-70%,其次为CO2泡沫驱和表面活性剂化学驱,可达40%以上,而烟道气／污水交替和微生物驱较低。大庆西部斜坡江55区块油藏埋藏深度浅,油藏温度低,油层厚度比较薄,直井冷采产量很低,因此开发该油藏的比较可能的开采方式有水平井冷采,水平井蒸汽吞吐及水平井蒸汽驱。针对上述三种开发方式,利用CMG数值模拟软件在三维地质建模的基础上,进行历史拟合,改变水平段长度、油层厚度、井距、初始含油饱和度、周期注汽量等参数,预测开发效果,对比生产效果确定合理的开发方式,确定了合理的生产参数。模拟结果表明：冷采的采油速度和采出程度很低,冷采水平段长度700m为宜；水平井水平段长度300m时蒸汽驱和蒸汽吞吐总体效果比较好；蒸汽干度要达到0.4之上；吞吐三周期之后转蒸汽驱效果最好；无论热采还是冷采,井距越大,采出程度越低；油层越厚,采出程度越高。并对大庆西部江55区块进行经济评价,评价结果表明：水平井热采明显比冷采经济效益好；在高油价情况下,蒸汽驱的净现值最大；蒸汽吞吐的内部收益率最高；油层越厚,经济效益越好。更多还原

【Abstract】 Heavy oil reservoir have characteristics with big resource potential and wide distribution area in the west of Daqing, mainly gathered in the west slope belt edge of Songliao basin, various types of reserves that has been submitted is 4372.3×104t, it is a important block for maintaining high and stable productivity in Daqing oilfield, which keep encouraging prospects. This paper is based on the actual problems of heavy oil reservoir in the development, on the basis of summing up predecessors’ achievements, potential evaluation and the optimization of development methods for heavy oil in the west of Daqing are presented to provide some theoretical basis and available technology for high efficient development of Daqing oilfield based on organical integration of oil and gas field development geology, reservoir engineering principles, physical simulation experiment and reservoir numerical simulation, mainly completed the following research work:We start from the regional geology and evaluation of static and dynamic factors of reservoir formation, the distribution of oil, gas and water, the sources of heavy oil, migration pathways and accumulation patterns are analyzed. Unconformity surface is the main pathway of oil and gas transverse migration, though faults are not the main pathways of oil and gas migration, they can connect sand body and become the pathways of oil and gas lateral migration. When oil and gas meet favorable accumulation conditions, they can be gathered in formation, thus favorable oil and gas blocks such as Talahong, Pingyang, Alaxin, Erzhan, Jiangqiao and Fula Erji etc are formed. Analyzing deeply the oil, gas and water distribution rules of every reservoir provides scientific basis for making development scheme. Through analyzing hydrocarbon-generating conditions and components contrast of heavy oil in the west slope area, it is indicated that the most crude oil of west slope area is not autogenous, but the product of distant migration. The gentle slope belt of structure has a control function on oil and gas accumulation. Structure, lithology and the matching relation of faults etc can joint control hydrocarbon accumulation. It’s concluded that main controlling factors of accumulation for heavy oil in the west of Daqing are:unconformity surface migration, fault ease, oil control of gentle slope and composite control of reservoir.The reservoir evaluation of western slope area is difficult, mainly showed in two aspects: in reservoir distribution, it presents that transverse variety of reservoir is big, sand body development is discontinuous and objective stratum is onefold; in reservoir type, it presents the increase of structural lithologic and lithologic reservoirs. Through dissecting losing Wells and synthesizing deposition, structure and accumulation characteristics, target suggestions of advantageous area for the main Saertu and Gaotaizi reservoir in the west slope area of Daqing are put forward. Through analyzing the geology of losing Wells and high-yield wells, favorable reservoirs are formed only when structure, sand body, reservoir are matched organically. A set of new methods for analyzing and seeking oil in blank area, extension area, the redevelopment area of remaining oil (encryption area) in the west of Daqing are formed. Applying multiple technologies such as seismic interpretation, reservoir prediction, sedimentary facies and fine sand anatomy, the approach of sub-blocks and sub-reservoir selection is carried out step by step under the guidance of main controlling factors of accumulation. With the multiple controlling factors of accumulation such as the structure, reservoir, reservoir fluid distribution etc, the potential for heavy oil resource in the west of Daqing is evaluated, geological reserves of A Laxin area, Erzhan area, Pingyang area and Jiangqiao area is estimated.Indoor experiments are done with the natural core of heavy oil block in the west of Daqing oilfield for optimization of different development methods. Various displacement experiments such as hot water flooding, steam flooding, chemical flooding, foam flooding, flue gas drive, microbial flooding etc are launched in order to optimize different development methods by parameter comparison and analysis of each displacement methods such as moisture content, recovery,injection pv, injection time and injection concentration etc. Experimental results show that the ultimate recovery of steam flooding and hot water flooding is highest, can be up to 50～70%; followed by CO2 foam flooding and surfactant chemical flooding, can reach more than 40%; however, the ultimate recovery of alternate flue gas/sewage and microbial flooding is relatively low.In view of characteristics of shallow buried depth, low reservoir temperature, small reservoir thickness and low production level of vertical cold production in jiang 55 block in the western slope of Daqing, so the preferable methods of developing the reservoir are horizontal cold production, horizontal steam stimulation and horizontal steam flooding. For different development methods such as horizontal cold production, horizontal steam stimulation and horizontal steam flooding, CMG numerical simulation software based on three-dimensional geological modeling are utilized to carry out history matching and predict their respective development effects by changing parameters such as horizontal length, reservoir thickness, well spacing, initial oil saturation, the quantity of cycle steam injection etc, development methods and production parameters are determined by comparing production effects. Simulation results indicate that oil producing rate and recovery percent of cold production are very low, advisable horizontal length of cold production is 700m; horizontal length of horizontal wells is 300m when the overall effect of steam flooding and steam stimulation is better; steam quality is 0.4 at least; the effect is best when steam flooding is performed after three stimulation cycles; for both cold production and thermal production, the bigger the well spacing is, the lower the recovery percent is; the thicker the oil reservoir is, the higher the recovery percent is. Economic evaluation in jiang55 block in the west of Daqing show that economic benefits of thermal recovery for horizontal well are significantly more qualified than cold production; net present value of Steam flooding is the largest in the case of high oil prices; internal rate of return of steam stimulation is the highest; the thicker the oil reservoir is, the better the economic benefit is.更多还原