塔河油田碳酸盐岩储层有效性测井评价实践与思考

塔河油田奥陶系已经勘探开发十几年了,目前除了在塔河继续精细勘探,也正在加大塔河之外的勘探.近几年塔中、玉北奥陶系碳酸盐岩储层勘探实践表明,储层有效性评价越来越显得重要.针对塔河油田奥陶系碳酸盐岩缝洞型储层,从测井响应特征分析入手,在岩心、成像测井、常规测井相互标定的基础上,细化溶孔、裂缝和溶洞型储层的分类,建立塔河油田奥陶系碳酸盐岩储层有效性测井识别与评价方法.对溶洞型储层采用自然伽马与视地层水电阻率交会方法进行有效性评价.对于裂缝孔洞型储层还可以利用电成像局部电阻率法评价储层有效性.实践表明,这两种方法可以较好解决因泥质充填造成的储层有效性评价问题.对于因储层类型不同,或具体说因裂缝发育强弱造成储层有效性差异的裂缝孔洞型储层有效性评价,通过"四性"关系及数模研究,提出定渗透率、变孔洞孔隙度、变裂缝孔隙度的储层渗流评价模型.实际应用表明,储层渗流评价方法提高了测井解释符合率,为塔里木盆地碳酸盐岩储层有效性评价、完井方案制定和储量参数计算提供了依据.     

埕岛油田埕北30潜山复杂岩性储层测井定量评价

埕岛油田埕北３０潜山是以碳酸盐岩、花岗片麻岩为主的复杂岩性裂缝性油气藏,从大量的基础测井资料入手,运用三孔隙度交会法对曲线进行标准化。将常规测井解释与核磁共振测井解释相结合,建立了孔、渗、饱参数的定量解释模型。利用Ｐｅｔｒｏｐｈｙｓｉｃｓ软件包实现了复杂的岩性、裂缝性油藏储层参数的定量解释。     

基于常规测井的花茶油田碳酸盐岩储层评价技术

百色盆地花茶油田区块小、断块多,其碳酸盐岩储层以裂缝溶洞型为主。影响储集空间性能的主要因素是构造应力和风化淋滤作用。该类储集层的特点是储集空间类型多、复杂,非均质性极强,横向可对比性较差,对其储层的正确评价比较困难。从基础资料入手,分析该类储层特征,建立了储层的孔隙度、渗透率、饱和度参数的解释模型,实现了裂缝发育程度评价,使用数学方法研究出多种有效的流体性质判别方法,综合岩心的观察、测井新技术对该地区的碳酸盐岩储层进行研究和评价。初步形成了一套用常规测井资料综合评价花茶油田碳酸盐岩储层的技术,实际应用效果比较显著,满足油田开发的要求。     

A multiple-continuum model for simulating single-phase and multiphase flow in naturally fractured vuggy reservoirs

The existence of vugs or cavities in naturally fractured reservoirs has long been observed. Even though these vugs are known for their large attribution to reserves of oil, natural gas, or groundwater, few quantitative investigations of fractured vuggy reservoirs have been conducted. In this paper, a multiple-continuum conceptual model is presented, based on geological data and observations of core samples from carbonate formations in China, to investigate single-phase and multiphase flow behavior in such vuggy fractured reservoirs. The conceptual model has been implemented into a three-dimensional, three-phase reservoir simulator with a generalized multiple-continuum modeling approach. The conceptual model considers fractured vuggy rock as a triple- or multiple-continuum medium, consisting of (1) highly permeable and well-connected fractures, (2) low-permeability rock matrix, and (3) various-sized vugs. The matrix system may contain a large number of small or isolated cavities, whereas vugs are larger cavities, indirectly connected to fractures through small fractures, microfractures or matrix. Similar to the conventional double-porosity model, the fracture continuum is primarily responsible for the occurrence of global flow, while vuggy and matrix continua, providing storage space, are locally connected to each other and interacting with globally connecting fractures. In addition, flow in fractured vuggy reservoirs may be further complicated by occurrence of non-Darcy's and other nonlinear flow behavior, because of large pore space and high-permeability flow channels. To account for such complicated flow regime, our model formulation includes non-Darcy flow using the multiphase extension of the Forchheimer equation as well as flow according to parallel-wall fracture and tube models, based on solutions of flow through a parallel-wall, uniform fracture and Hagen-Poiseuille tube flow.     

基于FORWARD平台的碳酸盐岩储层测井评价系统的开发与应用

碳酸盐岩裂缝性储层以其自身独有的孔隙空间结构而区别于孔隙性砂岩储层。它的低孔、各向异性、非均质性3大特点给测井评价带来了多解性、模糊性、不确定性，使碳酸盐岩裂缝性储层测井评价成为一个相当棘手的难题。基于FORWARD平台，利用WellBase软件开发工具包SDK开发了一套碳酸盐岩储层测井评价软件系统，将测井资料与岩心、录井，试油等地质资料相结合，编制了粘土分析、储层参数精细评价、横波估算、岩石力学参数计算、裂缝综合评价、地层应力分析、有效厚度划分、成果输出等模块，实现了复杂碳酸盐岩储层测井评价人机交互解释。     

对标产能的碳酸盐岩储集层测井分类评价——以塔里木盆地托甫台地区一间房组为例

孔隙类型多样是塔里木盆地托甫台地区中奥陶统一间房组碳酸盐岩储集层非均质性强的主要原因，储集层有效性难以评价。在岩心和薄片观察的基础上，依据成像测井资料，将碳酸盐岩孔洞分为溶蚀孔和洞穴；裂缝分为构造缝、溶蚀缝和压溶缝。根据孔洞和裂缝的组合形式，将研究区一间房组碳酸盐岩储集层划分为裂缝型、裂缝-孔洞型和孔洞型。综合导电效率、裂缝孔隙度和深侧向电阻率变化幅度，建立了储集层类型的定量划分标准，孔洞型储集层导电效率小于0.008，裂缝孔隙度小于0.13%；裂缝-孔洞型储集层导电效率为0.008～0.024，裂缝孔隙度为0.13%～0.60%；裂缝型储集层导电效率大于0.024，裂缝孔隙度大于0.60%。依据累计有效孔隙厚度、平均有效孔隙度以及产能，建立了裂缝-孔洞型储集层和孔洞型储集层分类判别图版。托甫台地区一间房组裂缝-孔洞型储集层和孔洞型储集层均主要为Ⅱ类储集层，测试日产液量分别超过55 t和50 t。     

四川盆地茅口组岩溶缝洞型储层有效性测井评价

针对四川盆地茅口组碳酸盐岩储层非均质性强、储集空间类型多样、储层有效性评价困难等问题,进行了测井评价研究。通过分析该地区茅口组缝洞型储层岩石孔隙结构,基于三孔隙度模型,利用胶结指数与总孔隙度、连通缝洞孔隙度、孤立缝洞孔隙度的关系,进行了储层储集空间划分。在此基础上,结合岩心刻度测井,在微电阻率扫描成像测井信息中提取视孔隙度谱和视地层水电阻率谱的均值与方差,以及裂缝孔隙度等反应孔、洞、缝的敏感性参数,并结合试气资料,建立了储层有效性评价标准:孔隙性、孔洞型储层,电成像视孔隙度谱均值大于1.9、方差大于1.2的为Ⅰ类储层,均值大于1.7、方差大于0.9的为Ⅱ类储层;裂缝性储层,Ⅰ类储层裂缝孔隙度大于0.30,Ⅱ类储层裂缝孔隙度在0.05～0.30。裂缝的连通会明显改善储层的有效性,针对孔隙性–裂缝性、孔洞型–裂缝性储层,Ⅰ类储层视地层水电阻率谱均值大于700、方差大于300,Ⅱ类储层视地层水电阻率谱均值500～700,方差100～300。依据该评价标准,对该地区20口探井进行了二次解释,有效提高了缝洞型储层解释的符合率,取得了较好的应用效果。     

井打在大尺度溶洞内的缝洞型油藏试井模型

天然缝洞型碳酸盐岩油藏中存在大尺度溶洞。鉴于钻井过程中会出现钻杆放空、泥浆大量漏失等现象,建立了井打在大尺度溶洞内的试井解释物理数学模型。通过格林函数和Laplace变换法求得了拉氏空间井底压力表达式,对影响井底压力动态的主要因素进行了分析。结果表明,当井打在洞内时,由于洞内的渗透性要远好于洞外地层,因此压力导数曲线后期出现明显上翘,溶洞的大小主要影响压力从洞内传播到洞外的时间长短。以缝洞型碳酸盐岩油藏中溶洞内一口井为实例对其进行了试井解释,验证了该数学模型。     

微电阻率成像测井资料在塔河油田缝洞型储层综合评价中的应用

塔河油田碳酸盐岩储层具有低孔、低渗、非均质性和各向异性强等特点，储层的储、渗机理十分复杂。微电阻率成像（FMI）测井资料能够描述地下岩层的沉积特征，因此，可以依据碳酸盐岩地层的FMI测井响应特征，对碳酸盐岩储层进行评价。介绍了FMI测井解释结果的多种地质应用；给出了常规测井资料和FMI测井资料对岩心的深度归位和空间方位归位的方法原理和实现步骤；利用统计方法建立了裂缝参数的定量估算关系；通过与常规测井等资料的对比，建立了储层分级标准，并利用FMI测井资料对储层进行了分级。多口井的应用结果表明，利用FMI成像测井资料对缝洞型储层的评价结果与录井油气显示和测试结果较吻合。     

深层高压碳酸盐岩气藏孔隙结构特征及衰竭开发规律

深层碳酸盐岩气藏孔隙结构复杂,产能差异大,气藏高效开发和长期稳产面临挑战,急需开展地层条件下衰竭开发规律的针对性研究。为此,采用二级CT扫描技术精细描述了气藏储层的孔隙结构特征,并通过岩心实验研究地层条件下孔隙结构和束缚水对衰竭开发的影响规律。结果表明：孔洞和裂缝的发育与分布不均是该类气藏非均质性强、产能差异大的主要原因;产气量主要受孔隙度的控制,阶段采出程度与渗透率接近对数关系;当井底压力为15 MPa时,孔隙型、孔洞型、裂缝-孔隙型和裂缝-孔洞型储层的平均阶段采出程度分别为47.43%、48.21%、59.90%、62.14%;裂缝-孔洞型储层的储量、产气量、阶段采出程度均相对较高;孔洞型储层的储量高、产气速度低,“高孔低产”特征明显;裂缝-孔隙型储层的储量低、产气速度快,稳产周期短;孔隙型储层的储量和产气速度均比较低。研究结果可为深层高压碳酸盐岩气藏开发方案设计提供理论依据。     

Anisotropic characteristics of electrical responses of fractured reservoir with multiple sets of fractures

In fractured reservoirs, the fractures not but also form the main flow channels which connect productivity of reservoirs. However, because of the only provide the storage space for hydrocarbons, the pores of the matrix, so fractures dominate the heterogeneity and randomness of the distribution of fractures, exploration and evaluation of fractured reservoirs is still one of the most difficult problems in the oil industry. In recent years, seismic anisotropy has been applied to the assessment of fractured formations, whereas electrical anisotropy which is more intense in fractured formations than seismic anisotropy has not been studied or used so extensively. In this study, fractured reservoir models which considered multiple sets of fractures with smooth and partly closed, rough surfaces were established based on the fractures and pore network, and the vertical and horizontal electrical resistivities were derived as a function of the matrix and fracture porosities according to Ohm＇s law. By using the anisotropic resistivity equations, variations of the electrical anisotropy of three types of fractured models under the conditions of free pressure and confining pressure were analyzed through the variations of the exerted pressure, matrix porosity, fracture aperture and formation water resistivity. The differences of the vertical and horizontal resistivities and the anisotropy between the connected and non-connected fractures were also analyzed. It is known from the simulated results that an increase of the confining pressure causes a decrease of electrical anisotropy because of the elasticity of the closed fractures and the decrease of the fracture aperture. For a fixed fracture porosity, the higher the matrix porosity, the weaker the electrical anisotropy in the rock formation.     

乐山—龙女寺古隆起深层海相碳酸盐岩地震勘探关键技术及其应用

四川盆地乐山—龙女寺古隆起寒武系及震旦系埋藏深度大,地震反射信号弱,同时储层受沉积相及岩溶作用的双重控制,基质物性差,缝洞发育,非均质性强,地震预测难度极大。为此,针对该类储层,通过地震采集、处理、解释一体化联合攻关,开展了三维宽方位地震采集,地震资料二、三维连片处理,构造精细解释,低孔渗储层定量预测,缝洞体识别,烃类检测等技术攻关,逐步建立起一套适用于该区深层碳酸盐岩古老气藏的地震勘探技术系列,取得了很好的应用效果。高精度的地震预测成果有力地支撑了该区油气勘探部署和天然气三级地质储量的提交,技术的进步和创新极大地提升了天然气勘探成效,促进了四川盆地深层碳酸盐岩气藏勘探的突破和大型气田的发现。     

电成像测井在东濮凹陷裂缝性砂岩储层评价中的应用

为有效识别和精确评价以"双孔介质"为特征的东濮凹陷三叠系致密砂岩裂缝性储层,通过对电成像测井资料的地质应用研究,完善了其在裂缝定性识别与定量评价、地层产状描述、井旁构造分析、地应力分析及岩性识别方面的应用。用岩心刻度电成像测井(EMI)、再用电成像测井刻度常规测井,在地质条件及测试资料的约束下,总结出三叠系砂岩裂缝性储层的测井响应特征,进而形成了一套划分裂缝性储层的有效方法。据已测试的10口井分析,该评价方法的测井解释符合率达84.3%,提高了测井对三叠系裂缝性储层的识别能力。     

轮南潜山奥陶系碳酸盐岩储层孔洞发育特征

轮南奥陶系潜山碳酸盐岩储层基质孔隙度和渗透率很低,但溶蚀孔洞的发育改善了其储集条件。根据岩心观察和铸体薄片分析,论述了轮南潜山碳酸盐岩储层孔洞分布发育规律、孔洞充填特征及孔洞发育的控制因素,并分析了孔洞对储层的影响。认为孔洞的发育为轮南潜山油藏的提供了良好的储集空间,不仅形成孔洞型储层和洞穴型储层,而且发育的孔洞与裂缝相通,形成该地区重要的裂缝孔洞型储层。     

论缝洞型碳酸盐岩油气藏储量评估单元划分

缝洞型碳酸盐岩油气藏在年度新增探明储量中占有重要地位,但从储量落实程度看,较常规砂岩油气藏计算结果精度偏低。研究表明,缝洞型碳酸盐岩油气藏储集空间类型复杂,包括溶蚀洞穴、孔洞、孔隙及裂缝等,储集空间级差较大,以孔洞、裂缝为基础的传统的两级单元划分方法不尽合理。各类储集空间发育状况表明,裂缝型及孔隙型储层普遍发育|孔洞型和洞穴型储层呈透镜体状分布,空间分布连续性差,因此与孔隙型储层合并计算导致了各计算单元的平均孔隙度计算结果偏大。根据不同孔隙度的储层其含油饱和度具有“三段式”分布的特征,以及单层孔隙度值与裂缝发育情况,细分了储量计算单元,将储层划分为Ⅰ级(≥15%)、Ⅱ级(15%~5%)、Ⅲ级(<5%)及Ⅳ级(裂缝段)计算单元,从而有效地提高了油气储量评估结果的精度。     

Effective Approach for Fractured Carbonate Reservoir Petrophysical Logs Interpretation in an Iranian Offshore Oil Field

Abstract

Due to the lack of information about the porosity exponent (m) from core experiments, the impossibility of comparison between the results and the core data, and, finally, inattentiveness to fractured intervals, the correct determination of the porosity exponent value in the calculation of water saturation and also the core-log correlation have generally been neglected. In this article, an analysis of the Mishrif Unit was carried out in two wells in order to properly calculate the water saturation and determine the best producing intervals. Based on fractured zones detection and the results of petrophysical evaluation in the calculation of shale volume and true matrix properties for these zones, accurate values of the porosity (matched with core data) were used to determine the porosity exponent. Hence, one of the advantages of this study is applying the method introduced simply for the fractured parts of the reservoir unit, in order to obtain the correct value for water saturation. Detecting proper producing intervals in the Mishrif Unit was executed using integrated evaluation of petrophysical data, geological data, and core data using a new method of shaly carbonate formation interpretation based on petrophysical log results. In this method, a statistical parameter, P^½, was used. The results from the application of the method show better interpretation and water saturation calculation using petrophysical logs of fractured shaly carbonate formations in combination with other available methods in the petroleum community.     

论碳酸盐岩缝洞型油藏的滚动开发

塔河油田奥陶系缝洞型碳酸盐岩储集空间多样,非均质性极强,缝洞储集体发育,流体性质复杂。总结了15年塔河油田开发之实践经验,提出了缝洞型油藏的滚动开发程序、开发基本原则及开发方案设计要点,并以具体实例论述了缝洞型油藏滚动开发过程,为此类油藏的高效勘探开发提供了有益的借鉴。     

塔河油田奥陶系碳酸盐岩储层测井识别与评价

塔河油田奥陶系油藏属于多期构造和岩溶作用形成的岩溶缝洞型碳酸盐岩油藏,主要的储集空间是溶蚀的孔、洞、缝,具低孔、各向异性强、非均质性强三大特点,储层的测井识别与评价与砂岩油藏有很大的差别.以岩心标定为基础,总结了成像测井可识别的主要储层类型.在此基础上,研究了各种类型储层的常规测井响应特征及储层的测井识别方法,分析了影响储层判别的各种假储层现象及识别方法.在岩心、成像测井资料标定的基础上,建立了裂缝综合概率模型、双孔介质模型,实现了缝洞型碳酸盐岩储层的常规测井资料定量评价,在塔河油田奥陶系储层测井评价中取得了较好的效果.     

轮南潜山碳酸盐岩储集层三维渗透率建模

利用塔里木盆地轮南潜山碳酸盐岩储集层裂缝分布的分形规律定量研究结果,结合相关统计,构建出储集层三维建模的渗透率变异函数;根据测井、试井解释、地应力分析等资料,对参与渗透率建模的硬、软数据进行特殊处理;提出了裂缝型储集层渗透率建模新技术——分形预测结合序贯指标随机建模技术,综合各类资料,建立起轮南潜山桑南西地区裂缝型储集层三维渗透率参数模型,经油藏数值模拟与生产实际拟合验证,取得了很好的应用效果。     

南堡凹陷碳酸盐岩储集性能测井评价研究

针对南堡凹陷潜山碳酸盐岩勘探开发需求,基于基质孔隙和裂缝发育情况进行储集类型识别.利用横波和斯通利波测井资料分析储层有效性,快慢横波最大最小正交能量差较大时,斯通利波出现"V"字型干涉条纹,反射特征明显.基于总孔隙度、裂缝孔隙度、流体移动指数等测井成果信息构建综合判别指标,经自然产能刻度后实现对储集性能的定量评价,初步...