海相碳酸盐岩储层中增强储集性能遗迹组构的属性表征与制约机制

This project is an interdisciplinary forefront research subject of carbonate reservoir geology, sedimentology and ichnology, and takes the Ordivician carbonate reservoir of western Henan province and Tahe oilfield as the research objects. This work is to apply the theory of carbonate reservoir geology, sedimentolgy and ichnology and use a contrastive study of the field outcrop and core sample, meanwhile, combine the phenomenon of observation, sample test and mechanism analysis, to study the ichnofabric characteristics biogenically enhanced reservoir properties, capacity of reservoirs, spatial distribution regularities, controlling factor and restriction mechanism. By means of analyzing the physical property parameters of carbonate reservoir such as porosity, permeability, oil and water saturation modified by ichnofabrics, the textural heterogeneities and spatial distribution regularities of carbonate rock matrix reservoirs will be interpreted from biogenic viewpoint. Thus the property characterization of ichnofabrics biogenically enhanced reservoir capacity in carbonate reservoir will be realized and the controlling factor and restriction mechanism will be interpreted. It is of important theoretical and practical significance to enrich the geological theory of carbonate reservoir and guide the oil and gas exploration, estimation of reserves and choosing reasonable development scheme on the oil-gas reservoir. Moreover, because of the Ordovician strata covered directly by the coal-bearing strata of the late Palaeozoic, therefore, it is also of important guidance to control bottom water in view of the coal mine production safety in this study area.

本项目系储层地质学、沉积学和遗迹学等交叉学科的前沿性课题。拟选择"豫西和塔河油田"奥陶系海相碳酸盐岩储层作为研究对象；应用碳酸盐岩储层地质学、沉积学和遗迹学等地质学理论，采取"地上"与"井下"相对比、现象观测与机理分析相结合的研究方法，对海相碳酸盐岩中增强储集性能遗迹组构的发育特征、储集能力、分布规律、控制因素与制约机制进行研究；通过分析遗迹组构对碳酸盐岩储层孔隙度、渗透率和油水饱和度等物性参数的改造效应，从生物成因角度解释碳酸盐岩"基质储集体"的非均质性与分布规律；实现增强储集性能遗迹组构的属性表征，揭示影响增强储集性能遗迹组构发育的主控因素与制约机制。这对丰富海相碳酸盐岩储层地质学理论，指导该类油气藏远景勘探、储量计算与选择合理的开发方案具有重要意义。此外，豫西奥陶系直接被晚古生代含煤岩系覆盖，这项研究还对分析豫西煤层底板含水状况和煤矿安全生产过程中的底板水防治具有一定的指导作用。

本项目选择塔河油田奥陶系、塔北巴楚和豫西奥陶系露头海相生物扰动碳酸盐岩储层作为研究对象；应用碳酸盐岩储层地质学、沉积学和遗迹学等地质学理论，采取“地上”与“井下”相对比、现象观测与机理分析相结合的研究方法，对海相碳酸盐岩中增强储集性能遗迹组构的发育特征、储集能力、分布规律、控制因素与制约机制进行研究；通过分析遗迹组构对碳酸盐岩储层孔隙度、渗透率和油水饱和度等物性参数的改造效应，从生物成因角度解释了碳酸盐岩“基质储集体”的非均质性与分布规律，实现了增强储集性能遗迹组构的属性表征；并利用数字图像分析软件包对数字岩心图像中生物扰动区域进行了识别和定量表征；基于X射线显微镜构建生物扰动碳酸盐岩储层模型并提取生物扰动形态特征与孔隙特征参数，利用三维建模软件重构了遗迹组构内生物潜穴的空间结构和垂向演化规律，再现了生物扰动型储层的宏观非均质性与微观各向异性，为计算这类多孔介质储层的迂曲度、定量表征微观尺度上的渗流特征打下了基础；综合以上研究揭示了影响增强储集性能遗迹组构发育的主控因素与制约机制。该研究丰富了海相碳酸盐岩储层地质理论，对指导该类油气藏远景勘探、进行储量计算以及选择合理的开发方案具有指导意义。