We analyzed from meso-to microscale the chemical interaction (e.g., bleaching) between deep fluids and carbonate rocks in pelagic limestones exposed along the seismically active Gubbio normal fault (Northern Apennines), exhumed from ca. 2 km depth. Bleaching is enhanced by the exploitation of inherited stylolitic seams by fluids and is favored by the progressive leaching and mobilization of primary components (i.e., Ca, Fe, Pb, and Cu) and the precipitation of authigenic baryte due to temperature and/or redox potential contrast.

Analysis of fluid inclusions trapped in calcite veins in the damage zone precipitated from a H₂O–NaCl-bearing fluid(s), with low salinity (1.22–2.57 wt%NaCleq) and a range of trapping temperature between 107 °C and 185 °C, higher than the host rock peak T conditions. Analysis of fluid inclusions and noble gases from syn-kinematic calcite and mineralogy of altered rocks suggests a mixed contribution between crustal-derived fluids with diagenetic fluids containing sulphates and CO₂. We speculate that bleaching is a by-product of the circulation of such aggressive fluids with mixed contributions, likely mobilized during seismic event(s) and injected into the damage zone at shallow depths. Such processes, affecting the chemical-physical properties of limestones, are generally underestimated and should be considered when modelling hydraulic connectivity in fractured carbonate reservoirs.

我们从中尺度到微观尺度分析了深部流体和碳酸盐岩之间的化学相互作用（例如，白化），在沿地震活跃的古比奥正断层（北亚平宁山脉）暴露的中上层石灰岩中，从大约 10 年挖掘出来。2公里深度。漂白通过流体对继承的针石煤层的开采而增强，并且由于温度和/或氧化还原电位导致主要成分（即 Ca、Fe、Pb 和 Cu）的逐步浸出和迁移以及自生重晶石的沉淀有利于漂白对比。

_{分析由含 H 2} O-NaCl 流体沉淀的损伤区方解石脉中捕获的流体包裹体，盐度低（1.22-2.57 wt%NaCleq），捕获温度范围在 107 °C 和 185 °C 之间℃，高于主岩峰值 T 条件。对来自顺运动方解石和蚀变岩矿物学的流体包裹体和惰性气体的分析表明，地壳衍生流体与含有硫酸盐和 CO _{2的成岩流体之间存在混合贡献}. 我们推测白化是这种具有混合贡献的侵蚀性流体循环的副产品，可能在地震事件期间被调动并注入浅层的破坏区。这种影响石灰岩化学物理特性的过程通常被低估，在模拟裂缝性碳酸盐储层的水力连通性时应予以考虑。