利用CT图像与压汞核磁共振构建高精度三维数字岩心

Higher Precision 3D Digital Core Constructed by CT Scanning Image with Mercury Penetration and NMR

X射线CT扫描作为岩心孔隙结构研究的主要手段之一,遇到的最主要的难题是微米CT无法识别微孔隙。纳米CT能够反映岩心微孔隙的信息,在一定程度上弥补微米CT扫描的不足。纳米CT扫描岩样的尺寸很小,即使对于均质性较好的岩心,选取岩样时的位置不同,得到的岩心参数也会有所差异,对于非均质性强的岩心,结果差异会更大。针对该问题提出利用CT扫描图像与压汞核磁共振资料结合构建高精度三维数字岩心的方法。相比于微米扫描得到的数字岩心,该方法获取的数字岩心在孔隙度和渗透率上都有较大提升,与实验结果更为接近,为在取心难、实验难的碳酸盐岩、页岩储层开展数字岩石物理实验奠定了基础。

The X-Ray CT scanning is the main way to research the pore structure of core.With the deep applications many problems appeared.The main difficulty we faced presently is the balance between micron-CT and nano-CT.Although the nano-CT can reflect the information of micron pore which can improve the defect of micron-CT,core scanned by nano-CT is very small and the result is variable even for homogeneous core.With the heterogeneous core,the result is more differential.In this paper,we propose a new method to construct the higher precision 3D digital core by CT scanning images and the information of mercury penetration and NMR.Compared with the micron-CT,the porosity and permeability in this method are improved obviously and are more closed with experimental result.