基于数字岩心的碳酸盐岩孔隙结构对弹性性质的影响研究(上篇):图像处理与弹性模拟

Digital rock physics-based studies on effect of pore types on elastic properties of carbonate reservoir Part 1:Imaging processing and elastic modelling

碳酸盐岩复杂的孔隙结构如何影响其弹性性质一直是地球物理研究的难点问题,在此基础上如何半定量甚至是定量地对碳酸盐岩储层预测,特别是如何有效地获取孔隙结构参数相关的地震属性体一直是油气工业界追求的目标.本研究从数字岩心角度入手,联合测井以及地震数据尝试探究这一问题的解决方案,包括如下几个方面:(1)代表性碳酸盐岩储层样品获取;(2)CT扫描数字岩心数据体获取;(3)数字岩心数据的图像处理;(4)数字岩心数据的静态弹性模拟;(5)数字岩心子数据体的孔隙结构因子提取;(6)孔隙结构因子表征与分类下的弹性性质与孔隙度的定量化量版建立;(7)数字岩心-井-地震联合的孔隙度属性提取;(8)孔隙结构因子的地震属性体获取.本研究分为两篇系列文章上篇与下篇,上篇主要阐述如上提出的(1)—(4)方面,重点在于针对碳酸盐岩二值化图像处理的流程建立与验证,以及数字岩心静态弹性模拟的理论方面,这两方面是基于数字岩心获得精确的碳酸盐岩弹性性质模拟结果的关键所在;下篇主要阐述利用数字岩心数据获得孔隙结构因子的思路、理论与流程,以及为碳酸盐岩储层预测为目标而获得孔隙结构因子的地震属性体的实际应用方面.由于两篇文章共享数字岩心数据,同时所涉及的研究思路与流程形成一个有机整体,因此写成两篇系列文章而非两篇独立文章.本文为两篇系列文章的第一篇:上篇.

How the complex pore structure of carbonate rock affects the elastic properties of carbonate rock has always been a difficult problem in the research of geophysics.How to make semi-quantitative or even quantitative predictions of carbonate reservoirs on this basis,and in particular how to effectively obtain seismic attribute volume related to the pore structure parameters,have been pursued by the oil and gas industry.This study attempts to explore the solution to this problem from the perspective of digital cores,combined with well logging and seismic data,including:(1)Acquisition of representative carbonate reservoir samples;(2)Acquisition of CT scan digital core data volume;(3)Image processing of digital core data;(4)Static elastic simulation of digital core data;(5)Pore structure factor extraction of digital core sub-block data bodies;(6)Quantification of elastic properties and porosity under pore structure factor characterization and classification to establish a quantitative measurement board;(7)Extraction of porosity properties of digital core-well-seismic associations;(8)Acquisition of seismic property bodies for pore structure factors.This study is divided into two article series Part 1 and Part 2.Part 1 focuses on aspects(1)—(4)as presented above,with an emphasis on the establishment of processes and validation of binarized image processing of carbonate rocks and the theoretical aspects of static elastic simulations of digital cores,both of which are key to obtaining accurate simulation results of the elastic properties of carbonate rocks based on digital cores.Part 2 focuses on the idea,theory and process of using digital core data to obtain pore structure factors,as well as the practical application of seismic attribute bodies that obtains pore structure factors for the purpose of carbonate reservoir prediction.This article is the first in a two-part series:Part 1.