This paper describes a viable nanoindentation-enhanced technique for screening hydraulic fracturing fluid additives via quantifying the effects of rock-fluid interactions on the mechanical properties of a clay-rich shale. Big data nanoindentation testing was conducted on both the intact shale and counterparts hydrothermally treated by four fracturing fluids, including water, KCl solution, and two surfactants, to extract simultaneously the statistical, cross-scale mechanical properties of both the bulk rock and individual constituent phases (e.g., clay matrix, carbonate, and quartz), accompanied by scanning electron microscopy for surface imaging and elemental mapping. Results show that pure water and KCl solution significantly degrade the clay matrix's Young's modulus and hardness by up to 39.4–42.5% and 42.9–57.1%, respectively, which can be mitigated or prevented by appropriate surfactant additives. The physicochemical rock-fluid interactions, such as dissolution of carbonate, are mainly responsible for the property degradation, as evidenced by the hydrothermal treatment-induced large cavities and secondary pores on the surface that tend to impair microstructural integrity of the shale. The big data nanoindentation technique can be implemented as an adaptive toolkit for screening, tailoring, and optimizing the chemical additives in fracturing fluids used for a specific shale formation to prevent shale softening, protect reservoir stability, and maximize well production.

本文介绍了一种可行的纳米压痕增强技术，该技术可通过定量分析岩石-流体相互作用对富粘土页岩力学性能的影响来筛选水力压裂液添加剂。对完整的页岩和相应的页岩进行了大数据纳米压痕测试，并通过四种压裂液（包括水，KCl溶液和两种表面活性剂）对水进行了热处理，以同时提取块岩和各个组成相的统计，跨尺度力学性能（例如粘土基质，碳酸盐和石英），并伴有用于表面成像和元素映射的扫描电子显微镜。结果表明，纯净水和KCl溶液分别使粘土基质的杨氏模量和硬度显着降低，分别高达39.4–42.5％和42.9–57.1％。可以通过适当的表面活性剂添加剂减轻或预防这种情况。物理化学的岩石-流体相互作用，例如碳酸盐的溶解，是造成性能下降的主要原因，水热处理引起的大孔洞和次生孔隙会削弱页岩的微结构完整性，这证明了这一点。大数据纳米压痕技术可以用作适应性工具包，用于筛选，定制和优化用于特定页岩地层的压裂液中的化学添加剂，以防止页岩软化，保护储层稳定性并最大化油井产量。如通过水热处理引起的大孔和表层次生孔隙所证明的那样，这些孔隙和孔隙往往会损害页岩的微结构完整性。大数据纳米压痕技术可以用作适应性工具包，用于筛选，定制和优化用于特定页岩地层的压裂液中的化学添加剂，以防止页岩软化，保护储层稳定性并最大化油井产量。如通过水热处理引起的大孔和表层次生孔隙所证明的那样，这些孔隙和孔隙往往会损害页岩的微结构完整性。大数据纳米压痕技术可以用作适应性工具包，用于筛选，定制和优化用于特定页岩地层的压裂液中的化学添加剂，以防止页岩软化，保护储层稳定性并最大化油井产量。