Abstract Heterolithic thin beds reservoirs contain significant amounts of hydrocarbons. We characterized the reservoir properties (sandstone connectivity, continuity and permeability) of sandstone layers in heterolithic rocks using three-dimensional imaging and analysis of heterolithic core plugs and mini plugs. The high-resolution three-dimensional models of the samples are smaller than a typical reservoir model grid block and similar the millimetre-to-centimetre beddings in heterolithic rocks. We find that the key to reservoir quality in heterolithic rocks is the connectivity and continuity of thin reservoir sandstone layers. Also, we show that these well connected and continuous thin sandstone layers have higher effective permeabilities that are comparable to a reference reservoir sandstone. These results can provide further information as to why some low resistivity heterolithic intervals with low net-to-gross values of the sandstone produced a significant amount of hydrocarbon despite lower production forecast based on well logs and core plug data. Determining the connectivity and continuity of thin sandstone layers is difficult due to limitations of well logs and core plug analysis that do not resolve and capture the connectivity of thin beddings. We show that 3-D Image Visualization is effective in characterizing the connectivity and continuity of thin sandstone layers in heterolithic rocks. Also, our Digital Core Analysis method computed permeability of thin sandstone layers in 3-D models of mini plugs representing thin sandstone layers in heterolithic core plugs. Our results represent information and reservoir properties at the millimetre-to-centimetre scale that are similar to the thickness of thin sandstone beddings in heterolithic rocks.

中文翻译：

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数字岩心分析：改进异质岩中薄砂岩层的连通性和渗透率表征

摘要 杂岩薄层储层含有大量的烃类。我们使用异岩岩心塞和微型岩塞的三维成像和分析来表征异岩岩中砂岩层的储层性质（砂岩连通性、连续性和渗透率）。样品的高分辨率三维模型小于典型的储层模型网格块，类似于异质岩中毫米到厘米的层理。我们发现，异质岩储层质量的关键是储层薄砂岩层的连通性和连续性。此外，我们表明这些连接良好且连续的薄砂岩层具有更高的有效渗透率，可与参考储层砂岩相媲美。这些结果可以提供进一步的信息，说明为什么尽管基于测井和岩心塞数据的产量预测较低，但一些具有低砂岩净毛值的低电阻率杂岩层段却产生了大量的碳氢化合物。确定薄砂岩层的连通性和连续性是困难的，因为测井和岩心塞分析的局限性无法解析和捕获薄层理的连通性。我们表明 3-D 图像可视化可有效表征异质岩中薄砂岩层的连通性和连续性。此外，我们的数字岩心分析方法计算了代表异质岩心塞中薄砂岩层的微型塞子 3-D 模型中薄砂岩层的渗透率。