Abstract Core data play a significant role in analyses of fundamental petrophysical properties, such as porosity and pore size distribution (PSD), which can be used to estimate the storage capacity and recovery rate of hydrocarbons. However, coring is time-consuming, and it is sometimes difficult to retrieve an intact core, particularly from coal reservoirs that are characterized by low mechanical strength and development of fractures. In most cases, only drill cuttings are available for analysis. Therefore, it is important to determine whether drill cuttings can adequately represent formation properties such as porosity and PSD. In this study, coal samples were prepared for analysis, including three groups of artificial drill cuttings—group-A (particle size of 1.00–1.70 mm), group-B (2.36–3.35 mm), and group-C (4.75–6.70 mm)—as well as one core plug. Nuclear magnetic resonance (NMR) measurements and mercury intrusion porosimetry (MIP) were performed to determine the porosity and PSD. The results for the porosity and PSD from the three groups of cuttings agree well with those from the core plug, which suggests that the effects of mechanical-pulverization and size fractionation during the sample preparation can be neglected for cuttings with particle sizes of ≥1 mm in most cases. The exception is one sample that having high mineral contents, because many mineral blocked pores in the sample can be released during mechanical-pulverization. The recommended particle size of drill cuttings for determining the porosity and PSD is 1–1.7 mm, which can provide accurate analytical results and avoid interference from other factors such as wellbore collapse, particle gravity dispersion, and drilling mud contamination.

中文翻译：

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岩屑能否代替岩心进行煤的孔隙度和孔径分布分析？

摘要 岩心数据在孔隙度和孔径分布 (PSD) 等基本岩石物理特性分析中发挥着重要作用，可用于估算碳氢化合物的存储容量和采收率。然而，取心很费时，有时很难取回完整的岩心，特别是从机械强度低和裂缝发育的煤层中。在大多数情况下，只有钻屑可用于分析。因此，确定钻屑是否能够充分代表孔隙度和 PSD 等地层特性非常重要。本研究准备煤样进行分析，包括三组人工钻屑——A组（粒径1.00-1.70 mm）、B组（2.36-3.35 mm）和C组（4.75-6 . 70 毫米）—以及一个芯塞。进行核磁共振 (NMR) 测量和压汞孔隙率 (MIP) 以确定孔隙率和 PSD。三组岩屑的孔隙率和PSD结果与岩心塞的结果吻合良好，表明对于粒径≥1 mm的岩屑，在样品制备过程中机械粉碎和粒度分级的影响可以忽略不计在大多数情况下。一个例外是一种矿物含量高的样品，因为在机械粉碎过程中，许多矿物堵塞了样品中的孔隙。确定孔隙度和 PSD 的钻屑推荐粒径为 1-1.7 mm，可以提供准确的分析结果并避免井筒坍塌、