【作者】 李静；

【导师】 查明；

【作者基本信息】 中国石油大学 ， 地质资源与地质工程， 2011， 博士

【摘要】 潜山型碳酸盐岩裂缝性油气藏是近年来石油增储上产的重要新领域,本学位论文以冀中坳陷任丘潜山型碳酸盐岩油气藏为例,对潜山型碳酸盐岩储集层裂缝形成的地质背景、储层的微观特征、地应力的分布情况、裂缝的分布规律以及影响裂缝发育的控制因素等进行了系统而深入的研究,内容包括基础实验、理论研究、数值模拟、自行开发软件四大部分,分别从微观和宏观不同尺度开展研究。主要工作及研究成果如下:(1)结合野外观察和研究资料对研究区的区域地质特征、储集空间特征、构造演化特征进行了研究,确定了断裂构造与裂缝的空间匹配关系,为裂缝的综合研究提供了基础资料。(2)利用扫描电镜、X射线能谱、显微荧光、红外光谱、拉曼光谱等多种技术对研究区储层进行了微观特征分析。确定了研究区油藏的成藏期次;对油气充注时古压力进行了恢复;由实验数据形成了光谱立方体数据库,从中提取了有机烃的基团甲基、亚甲基和缔合羟基的特征波长的单色图像;并利用图像光谱信息的数据融合技术进行了数据处理和综合分析,得出了这些化合物在样品中的空间分布情况;实现了利用显微荧光、红外光谱和拉曼光谱成像分析系统在光谱和空间两个方面对岩心样品进行分析和识别;得到岩心样品中不同化学组分、结构和基团的空间分布图等,从而更直观地揭示了不同烃类在岩石中的分布情况、孔隙的连通性等信息,为进一步的裂缝综合预测研究提供了依据。(3)基于岩石声学特性和力学特性之间的关系,建立了利用常规测井信息计算岩石力学参数的模型,并研究了储层岩石力学参数的随机性,预测分析了研究区储层岩石弹性模量及泊松比的概率分布类型,并得出其统计特征值,为下一步储层地应力的研究提供了基础资料。(4)鉴于潜山型碳酸盐岩储层所受的复杂多轴应力环境,考虑了地温场与地应力场的耦合作用,对研究区的地应力进行了系统研究。建立了以关键井点地应力的大小和方位为约束条件,利用多井多目标约束的最优化技术来确定储层岩石地应力分布规律的模型,并获取了任丘雾迷山组油藏储层平面内三向主应力的分布规律,回归拟合了研究区域地应力随深度变化的关系曲线。研究成果为:最大和最小水平主应力、最大剪切应力、最大和最小水平主压应力的大小及方向等成果图。通过模拟值与实测值的对比研究,发现这一方法确定的地应力符合实际情况,为下一步研究区储层裂缝的预测研究奠定了基础。(5)建立了利用Monte Carlo法随机有限元模拟技术预测分析碳酸盐岩储层岩石裂缝发育情况的模型方法。利用库伦-摩尔剪切破裂准则和格里菲斯张破裂准则,计算得出研究区储层裂缝的剪切破裂率和张破裂率,分析结果表明,通过裂缝发育指数与裂缝密度间的拟合关系,得到裂缝发育指数、裂缝密度分布图等成果图,较好地预测分析了研究区储层裂缝密度分布规律,并且自行设计开发了“储层岩石裂缝预测分析”软件,对ANSYS的后处理模块做了较大的改进,不仅提高了工作效率,而且减少了人为误差,实现了论文理论研究方法向油田实际应用的转化。更多还原

【Abstract】 In recent years,carbonate fractured reservoirs of buried hills is an important research field on increasing production and reserve. In this paper,the carbonate reservoir of Renqiu buried hills in Jizhong depression is taken as an example,the geological background of crack formation,the microscopic characteristics,the distribution of crustal stress,the distribution of cracks and the factors which affect the development of the cracks were systematically and deeply researched. The concrete research contains basic experiment,theoretical research,numerical simulation and self-developed software. The main achievements are as follows:Firstly,the regional geology,reservoir features and tectonic evolution were analyzed by using field observation and other data. The space matching relationship between fractured structure and fracture was determined,providing basis for comprehensive research of fractures.Secondly,the microcosmic analysis of the reservoir was done by using various technologies such as scanning electric mirror, X-ray photoelectron spectroscopy ,fluorescence,Raman microprobe and infrared spectra. The fluid inclusions from Wumishan formation in Renqiu oilfield were tested and analyzed. On the basis of test data, palaeo-pressure of the reservoir was also calculated. Then core samples were analyzed and recognized in both space and spectrum. Especially,the experimental data from the system were processed and comprehensively studied by using data fusion technology of image spectral information. The distribution of different hydrocarbons in rock cores and the connectivity of pores were visually revealed,providing evidence for fracture prediction.Thirdly,based on the relationship between rock acoustic properties and mechanical properties,the effective model for the acquisition of rock mechanics parameters by using conventional well logging information was established. The type of probability distribution of rock elastic modulus and Poisson’s ratio were researched,and the statistical characteristics was obtained.Fourthly,in consideration of the complicated multi-axial stress of carbonate reservoir and the coupling effect of geothermal field and crustal stress field,the crustal stress was systematically studied. The model which determined the distribution of the reservoir stress was derived by using the method of multi-objective optimization techniques. The distribution of principal stress and the fracture pressure of Wumishan Formation were obtained. The related curve of the principal stress versus the depth of researched area was obtained also. The research includes the maximum and the minimum horizontal principal stress,the maximum shear stress,the direction of the maximum and the minimum horizontal main compression stress,the index of fracture development etc. The results show that the numerical simulation is consistent with the actual measurements.Finally,the method of using Monte carlo random finite element simulation technology was proposed to predict and analyze the development of fracture in carbonate reservoirs. The shear and the broken fracture rate of the reservoir in the study area were calculated by using Mohr-coulomb and Griffith criterion. The result showed that the fitting relationship between the density and development index of the crack could better forecast and analyze the distribution rules of the fracture density. The self-developed software, named“Fracture of Carbonate Reservoir Analysis system”, not only improved the efficiency,but also avoided personal errors. The transformation from the theoretical approach to the practical application was implemented.更多还原