利用不稳定压力数据建立碳酸盐岩储集层模型

地质模型通常是根据地质信息,利用地球物理和岩石物理资料来建立.为了建立准确的碳酸盐岩油藏(伊朗海上油田)模型,不仅利用了地震和测井数据,也结合了该油田现有99井次的试井数据.在试井解释过程中观察到了许多特征,如封闭断层、水层、裂缝和分层系统,其中某些特征只能利用压力瞬态数据来识别,如地震数据中观察不到的一条封闭断层在试井曲线上则可识别.除了识别构造特征外,试井解释得到的渗透率数据也可用于绘制渗透率等值线图,而不再采用岩心分析得到的渗透率数据.试井得到的渗透率是泄油区域的有效渗透率,而岩心分析得到的渗透率并不能代表非均质油藏的渗透性.利用非稳态压力分析结果建立油藏模型,可以提高碳酸盐岩油藏建模的准确性.图6表1参8     

Stochastic surface modeling of deepwater depositional systems for improved reservoir models

High resolution reservoir models are often required for resource assessment and reservoir management. The reservoir models must reproduce geologically realistic heterogeneity that may affect predictions. An important heterogeneity in many deepwater depositional systems consists of facies variations controlled by geological events that lead to lobe geometries. A surface-based geostatistical scheme is presented to model high resolution lobes and their associated stacking patterns in a geometrically realistic manner. The lobes are constrained to match well data. Facies, porosity and permeability are then modeled within the lobe framework. Application to a reservoir with 36 wells demonstrates the practical applicability of the approach. This surface-based method may be readily extended to model other geometries in various reservoir settings.     

Using downhole temperature measurement to assist reservoir characterization and optimization

Without initial seismic or detailed geological information, reservoir characterization is difficult. Downhole temperature distribution in horizontal wells is an important source that helps to characterize the reservoir and understand the bottom-hole flow conditions. The temperature measurements are obtained from permanent monitoring systems such as downhole temperature gauges and fiber optic sensors. Additionally, production history and bottomhole pressures are usually readily available and are routinely used for history matching to improve the initial geological models. By combining the downhole temperature distribution and the production history, more reliable information can be extracted about the reservoir permeability distribution and bottomhole flow conditions in order to optimize the wellbore performance, particularly in horizontal wells.In this paper, a thermal model and a transient, 3D, multiphase flow reservoir model are used to calculate the wellbore temperature distribution in horizontal wells. By comparing the simulated temperature and the observed data, large-scale permeability trends in the reservoir are derived. These permeability trends are then incorporated as ‘secondary’ information in the geologic model building and history matching. The final outcome is a geologic model that has the constraints of both temperature and production history information.A synthetic case is presented to illustrate the procedure. The results show when using production history matching only without distributed temperature data along the wellbore, the water entry location in horizontal wells cannot be detected satisfactorily. By combining production history matching with downhole temperature distribution data in a wellbore, an improved geological model is developed that can match production history and locate water entries correctly. Based on the downhole flow conditions and the updated geological model, the well performance can be optimized by controlling the inflow rate distribution in a horizontal well.     

油藏描述中的建模技术

利用软件系统在工作站上将各种地质信息多层次交互应用,可从三维空间定性、定量地描述油气藏的储层沉积相、储层参数、流体的分布特征和变化规律。依据区域地质分析结合对钻井、粒度等资料的综合解释建立储层沉积相模型。应用算术平均法或权衡法等方法求取储层的渗透率和孔隙度等物性参数;用成岩系数来定量描述储集层成岩作用的综合效应,研究表明成岩系数与渗透率、孔隙度有较好的对应关系;应用渗透率的变异系数、突变系数和极差可研究储层的非均质性;在此基础上建立储层的参数模型。利用油气藏的特征参数建立其数学模型并对油气藏的相态类型进行早期判别。通过上述模型的建立达到为油藏数值模拟与制定开发方案提供精确的地质参数。     

随机建模在滴水泉区油藏描述中的应用

在新疆油田滴水泉滴12井区侏罗系八道湾组砂砾岩储层非均质建模中,针对储层描述的不确定性因素,利用井内外信息的随机性特点,综合运用测井数据、岩心描述数据、地震数据等多方面信息,以减少储层描述的不确定性。利用层序地层基准面旋回等时对比方法,进行单井单砂体细分对比,确定储层格架和沉积微相展布特点,建立地质数据库。在此基础上,用Petrel软件对该区块的油藏构造、沉积微相和油藏属性建立储层三维地质模型,从而使得油藏的非均质性描述和认识更为直观、合理,为油田增产提供了地质依据。     

塔巴庙大牛地低渗透气田试采动态预测研究

塔巴庙大牛地气田是无边底水定容弹性驱动的低渗透岩性气藏。在完成气藏流体相态拟合之后，利用大牛地气田地质研究成果所确定的单井各层物性参数，并结合构造形态和研究的目的层位，建立了三维地质模型，并完成了储量拟合，为了论证合理的开发井网和井距，并评价大牛地气田开发远景规划的可行性，利用建立的三维地质模型，分别对研究的3个目的层位进行了3套井网开发的指标预测；最后针对该气田试采井网部署，预测了该气田未来的试采开发指标，所得的研究结论有利于指导该气田试采开发生产。     

储层随机地质建模技术在油田开发中的应用

利用随机建模软件(RMS/STROM)对沙南油田浊积扇沉积储层开展了储层随机建模研究,根据浊积扇的沉积特点,采用了截断高斯、通用标点模拟等方法建立了浊积扇相模型,并利用60余口开发井的测井解释参数,通过数据分析、正态变换、变差分析,在浊积扇不同微相的控制下,建立了储层孔隙度、渗透率、含油饱和度等参数模型.并通过软件提供的网格粗化功能,将三维地质模型粗化为VIP数值模拟软件所需的地质模型,并通过数模软件的模拟测试,使得数值模拟结果具有更为可靠的地质依据,实现了地质研究到数值模拟的一体化.     

三角洲平原网状河砂体的地质概念模型及修正

三角洲平原网状河道侧向迁移频繁，河道砂体在横向上整体连片性虽好，但单砂体形态差异大，频繁分布低渗透条带和泥质夹层，根据长庆探区的三角洲平原网状河的心滩、边滩砂体特征，提出3种多层层间非均质地质概念模型，通过拟合试井动态数据来检验、修正概念模型、定量化模型参数，进而认识砂体类型和特征，初步评价单井产能。在油气藏开发评价初期阶段，这是研究砂体的有效手段。     

大牛地低渗透气藏压裂井试井曲线特征研究

从压裂井试井理论物理模型出发,分析了有限导流垂直裂缝井双线性流模型和三线性流模型在渗流形式和试井样版曲线上的差别。分别利用双线性流模型和三线性流模型对大牛地气藏压裂井的典型测试井进行了试井解释,从拟合效果和实际解释结果看,大牛地气藏压裂井符合三线性渗流规律。详细研究了大牛地气藏试井曲线形态特征,发现正常形态的测试曲线有4类典型曲线,异常形态的测试曲线有3类典型曲线。对不同形态特征的测试曲线的试井解释将获得不同的可靠性参数。研究结果可为大牛地气藏的试井分析提供指导,还可为其他低渗透油气藏提供借鉴和参考。     

预测井间储集层参数的相控模型法

在后期成岩作用影响不大的情况下，砂岩储集层物性与沉积微相之间关系密切。据此，针对砂岩储集层进行井间参数预测，研究砂岩厚度、孔隙度、渗透率的平面分布，提出建立井间储集层参数模型的相控模型法，勘察质是进行带地质约束的井间参数预估，即由井间沉积相地质信息提取储集层参数软信息，增补井间约束条件，与井点数据共同预测井间储集层参数。该方法适用于井控不足情况下的储集层描述。