碳酸盐岩台缘礁滩储层精细地质建模研究

Platform margin reef-shoal（PMRS）sediments are widely developed in the Permian and Triassic formations in the southern China and potential petroleum reservoirs in the PMRS have been becoming the major exploration targets in the marine carbonate formations. The complexities of the internal compositions in the PMRS depositional system, as well as strong reservoir heterogeneities, greatly limited petroleum exploration and development for the carbonate rocks.Therefore,the applicants try to choose typical PMRSs, mainly from the late Permian Changxing and early Triassic Feixianguan Formations in the eastern Sichuan-northern Hubei region, as main research targets, based on the fine sedimentary facies and reservoir characteristics analysis, to finely describe the microfacies types, the vertical superimposed types, and the dimensional distribution of high-frequency units. In combination with detailed studies for reservoir porosity properties and diagenetic characteristics, we try to establish a set of outcrop-reservoir-geological models, in order to reflect the dimensional distributions and heterogeneities for PMRS reservoirs. Then, comparing the outcrop-reservoir model with the subsurface reef-bank targets revealed from seismic-sedimentology researches, we try to create a set of approaches to identify and forecast potential favorable PMRS reservoirs. We will try hard to make some breakthrough in this study, which will be very helpful in elevating the academic researches in this field in China, and also significant for the marine carbonate rocks petroleum exploration & development in the southern China.

碳酸盐岩台地边缘礁滩沉积在我国南方二叠系-三叠系极为发育，台缘礁滩储层已成为我国南方海相油气勘探最主要的目标；由于台缘礁滩沉积体系内部构成复杂，储层非均质性强，从而极大地制约了该类油气藏勘探开发成效。本项目拟选择川东-鄂西地区晚二叠世长兴组-早三叠世飞仙关组台缘礁滩为主要研究对象，以典型露头剖面精细沉积相和储层特征写实分析为基础，对礁滩体沉积微相类型、高频单元的垂向叠加样式及空间展布进行精细刻画，结合储层物性和成岩特征等精细研究，拟建立一套能反映台缘礁滩储层空间展布及储层非均质性特征的露头储层地质模型；在此基础上，采用地震沉积学方法，将露头剖面储层地质模型与勘探区地下类似礁滩目标进行对比研究，试图建立一套台缘礁滩有利储集体识别和预测的方法，力争在碳酸盐岩礁滩精细露头地质建模和储层预测研究方面有所突破。该项目的实施有助于提升我国在该领域的研究水平，同时对我国南方海相油气勘探开发亦具现实意义

碳酸盐岩台地边缘礁滩沉积在我国极为发育，台缘礁滩储层已成为我国海相油气勘探最主要的目标.由于台缘礁滩沉积体系内部构成复杂，储层非均质性强，从而极大地制约了该类油气藏勘探开发成效。本项目以典型露头剖面精细沉积相和储层特征写实分析为基础，结合地下对比分析试图建立一套能反映台缘礁滩沉积微相、储层空间展布及储层非均质性特征的储层地质模型，力争在碳酸盐岩礁滩精细地质建模和储层预测研究方面有所突破。. 项目主要研究内容包括以下三个方面：①台缘礁滩露头沉积体系和相建模研究。选择典型台缘礁滩露头剖面，对台缘礁滩沉积体系的三维构成进行精细解剖，划分高频层序单元，剖析台缘礁滩沉积体系空间展布，建立台缘礁滩沉积微相动态演化模型。②台缘礁滩储层精细地质建模。以露头高频动态沉积微相建模为基础，分析储层纵横向分布规律、储层不均一特征等，建立具有预测功能的储层模型。③礁滩正演模型建立及礁滩储层分布预测。用地震沉积学的思路，对礁滩体或鲕粒滩体储层展布的三维空间特征进行精细刻画，建立台缘礁滩沉积储层识别及预测方法。. 本项目研究取得了以下方面创新性成果：1）按沉积体系和沉积微相构成单元动态的建立了台缘礁滩露头沉积模型。在高分辨率层序格架内总结出对台缘礁滩三维几何形态、内部构成以及各沉积微相空间配置关系等具有预测功能模式。2）提炼出一套能反映台缘礁滩储层非均质性并对储层展布具有预测功能的储层地质建模。在精细沉积体系建模研究基础上，剖析露头储层孔渗分布的非均质性和储层发育主控因素，通过露头与地下对比研究，建立碳酸盐岩台缘礁滩储层预测方法，指导该类碳酸盐岩储层的勘探开发工作。. 本项目研究提高了碳酸盐岩台缘礁滩储层预测精度和准确性，提升了我国在碳酸盐岩精细露头地质建模方面的研究水平，项目研究成果对四川、塔里木盆地海相深层碳酸盐岩油气勘探开发具有指导意义。