An image-based volumetric equation for estimating the prospective CO₂ mass storage resource potential for organic-rich shale formations has been developed using data obtained from advanced image analysis of Bakken Formation shale samples. The equation is a modification of the U.S. Department of Energy (DOE) National Energy Technology Laboratory’s (NETL’s) volumetric equation methodology for estimating the prospective CO₂ mass storage resource for shale formations. The current equation enhances DOE’s version by systematically deriving expressions for calculating efficiency factors based on analysis of high-resolution field-emission scanning electron microscopy (FESEM) shale images. FESEM images are used to obtain improved nanoscale porosity estimates for the shale matrix and OM. The calculation of the efficiency factors associated with free-phase storage and CO₂ adsorption onto solid surfaces are based on a ratio of connected-to-nonconnected porosity and the newly developed shared border analysis (SBA) method, respectively. The image-based equation described herein is structured so that it can be adapted and applied to other formation types by considering the specific mineralogy or matrix characteristics. Preliminary data used to illustrate the newly developed equation show that the Upper Bakken Shale (UBS) may have a lower prospective CO₂ storage resource potential than the Lower Bakken Shale (LBS) by about 65 %. Although these results are neither optimized for each lithofacies nor represent the Bakken formation regional scale, they are encouraging for unfractured shale samples and serve as a useful starting point for future evaluations at the regional scale.

使用从巴肯组页岩样品的高级图像分析获得的数据，开发了一种基于图像的体积方程式，用于估算富含有机物的页岩层的预期CO ₂大量存储资源潜力。该方程是美国能源部（DOE）国家能源技术实验室（NETL）的体积方程方法的修改，用于估算预期的CO ₂页岩地层的海量存储资源。当前的方程式通过对高分辨率场发射扫描电子显微镜（FESEM）页岩图像的分析，系统地推导计算效率因子的表达式，从而增强了DOE的版本。FESEM图像用于获得页岩基质和OM的改进的纳米级孔隙率估算值。与自由相存储和CO ₂相关的效率因子的计算固体表面上的吸附分别基于连通孔与非连通孔的比率和新开发的共享边界分析（SBA）方法。本文描述的基于图像的方程式经过构造，可以通过考虑特定的矿物学或基体特征使其适用于其他地层类型。用于说明新开发的方程式的初步数据显示，上巴肯页岩（UBS）的潜在CO ₂储存资源潜力可能比下巴肯页岩（LBS）低约65％。尽管这些结果既未针对每个岩相进行优化，也不代表Bakken地层区域尺度，但它们对于未破裂的页岩样品是令人鼓舞的，并且可作为将来在区域尺度进行评估的有用起点。