基于数字岩心的古龙页岩油储层含油饱和度建模方法及其应用  

Digital core-based modeling method and application of oil saturation in Gulong shale oil reservoir

作　　者：闫伟林[1,2] 章华兵 郑建东[1,2] 王文娟 张兆谦[1,2] 朱建华 YAN Weilin;ZHANG Huabing;ZHENG Jiandong;WANG Wenjuan;ZHANG Zhaoqian;ZHU Jianhua(Exploration and Development Research Institute of PetroChina Daqing Oilfield Co Ltd,Daqing 163712,China;Heilongjiang Provincial Key Laboratory of Continental Shale Oil,Daqing 163712,China)

机构地区：[1]中国石油大庆油田有限责任公司勘探开发研究院,黑龙江大庆163712 [2]黑龙江省陆相页岩油重点实验室,黑龙江大庆163712

出　　处：《大庆石油地质与开发》2022年第3期91-102,共12页Petroleum Geology & Oilfield Development in Daqing

基　　金：中国石油天然气股份有限公司重大科技专项“大庆古龙页岩油勘探开发理论与关键技术研究”(2021ZZ10)。

摘　　要：针对古龙页岩油储层黏土含量高、纹层页理与纳米孔发育、孔隙结构复杂导致传统驱替方式的岩电实验方法较难确定饱和度模型参数的问题,优选Simandoux饱和度模型作为古龙页岩油含油饱和度计算模型,并提出利用高精度的配套岩石物理实验分析方法确定关键岩电参数。该方法将微米级CT孔隙扫描与高精度矿物分布信息相结合,在保持样品尺度与图像分辨率的前提下将纳米级孔喉分布进行准确定位,构建高分辨率四维数字岩心孔隙格架,通过有限元法数字模拟分析页岩油储层在差异性含油等不同阶段的岩电参数变化规律,进而确定关键岩电参数。通过井A7等多口井的岩心分析数据检验,模型平均绝对误差为3.9%,精度能满足页岩油储量评价需求。该技术能够为古龙页岩油储层含油饱和度计算提供可靠的方法和模型,对其他类型页岩油饱和度评价也具有借鉴意义。Aiming at the problems of high clay content,well developed lamellation texture and nanopores,and complex pore structure in Gulong shale oil reservoir,it is difficult to determine the parameters of saturation model by conventional rock electrical experiment method.Simandoux saturation model is selected as the oil saturation calculation model for Gulong shale oil,and high-accuracy matching rock physics experiment analysis method is proposed to determine the key rock electrical parameters.This method combines micron-scale CT pore scanning with high-accuracy mineral distribution information,accurately locates nano-scale pore throats distribution under the premise of maintaining sample scale and image resolution,and establishes high-resolution 4D digital core pores framework.Numerical simulation of finite element method is applied to determine the variation law of rock electrical parameters of shale oil reservoir in different stages such as differential oil-bearing so as to determine the key rock electrical parameters.Average absolute error of the model is 3.9%after verification of core analysis data of several wells including Well A7,with accuracy meeting the needs of shale oil reserves evaluation.This technology provides reliable methods and models for calculation of shale oil saturation in Gulong area,and also provides reference for saturation evaluation of other types of shale oil.

关 键 词：古龙页岩油 数字岩心 数值模拟 岩电参数 含油饱和度 

分 类 号：TE311.2[石油与天然气工程—油气田开发工程]