At ten percent of sedimentary rocks, limestones are common geo-energy reservoirs. Being highly soluble, limestones are prone to fluid-assisted deformation and their mechanical behaviour likely susceptible to fluid chemistry. In this study, we saturated limestone samples with 0.4 M MgSO₄ or 0.4 M Na₂SO₄ CaCO₃-saturated solutions (naturally present in many reservoirs) or a reference CaCO₃-saturated solution for 1, 50 or 200 days prior to mechanical testing. Triaxial deformation tests were then performed at 7, 30, and 70 MPa of confining pressure room temperature, under drained conditions. Our results show that exposure to one different cation impacts the strength of this rock (up to $\frac{1}{2}$ of dry rock strength) and its failure dynamics, associated with different microstructural damage distribution. A 200 day exposure to MgSO₄ promotes strengthening whilst similar exposure to Na₂SO₄ leads to weakening. We posit that these strength changes may be related to changes in surface charges on the mineral surfaces. More data on fluid–rock interaction will be key to fully understand fracture propagation in natural carbonate formations.

石灰岩占沉积岩的10％，是常见的地能储层。石灰石是高度可溶的，易于流体辅助变形，其机械性能可能容易受到流体化学作用的影响。在这项研究中，我们先用0.4 M MgSO ₄或0.4 M Na ₂ SO ₄ CaCO ₃饱和溶液（在许多储层中自然存在）或参考CaCO ₃饱和溶液对石灰石样品进行饱和1、50或200天，然后进行机械处理测试。然后在排水条件下于7、30和70 MPa的密闭压力室温下进行三轴变形测试。我们的结果表明，暴露于一种不同的阳离子会影响该岩石的强度（最高$\frac{\mathrm{1个}}{2}$岩石强度的变化）及其破坏动力学，以及不同的微结构破坏分布。暴露于MgSO _4的200天可促进强化，而类似暴露于Na ₂ SO ₄则可导致减弱。我们假设这些强度变化可能与矿物表面的表面电荷变化有关。有关流体-岩石相互作用的更多数据将是全面了解天然碳酸盐岩地层中裂缝扩展的关键。