The Proterozoic carbonate rocks from Ribeira Belt in Rio Bonito Quarry, Southern Brazil, seem to evidence an intense hydrothermal alteration prominently indicated by three distinct dolomitization stages followed by a later dedolomitization one. This observation prompted a detailed study of the mineral phases derived of these processes, the carbonates involved in such, and the implications therein regarding the characterization of the hydrothermal dolomitization. Different phases of basinal, hydrothermal-magmatic, metamorphic and meteoric fluids were responsible by the crystallization of six distinct generations of dolomite in multistage events, which comply with different dolomitization models in literature. First, Mesoproterozoic limestones, from shallow to deep water platforms, were dolomitized (burial compaction model) by the replacement of diagenetic calcite with dolomites through the interaction of marine and basinal fluids. In pressure relief zones, the formation of the first gap-filling dolomite represented the sedimentary–metamorphic transition. During the Brasiliano–Pan African orogeny, the second dolomitization phase (tectonic model) occurred generating dolomite, inducing hydraulic fracturing and afterwards, yet another, precipitation of dolomite on the edges of fragments—thus forming a dolomitic breccia. The precipitation of the second gap-filling sample of dolomite took place simultaneously to the tectonic dolomitization phase and the hydraulic brecciation. During the third dolomitization stage (thermal convection model), hydrothermal-granitic fluids promoted the precipitation of saddle dolomite, infilling vugs. Subsequently, the dedolomitization process (thermal convection/meteoric model) ascribed to hydrothermal-granitic and meteoric fluids induced calcite, quartz, fluorite and apatite’s crystallization, infilling vugs in the dolomitic breccia.

来自巴西南部 Rio Bonito 采石场 Ribeira 带的元古代碳酸盐岩似乎证明了强烈的热液蚀变，这突出地表明了三个不同的白云石化阶段，随后是一个后来的去白云石化阶段。这一观察结果促使对这些过程产生的矿物相、参与其中的碳酸盐以及其中对热液白云石化特征的影响进行了详细研究。不同阶段的盆地流体、热液-岩浆流体、变质流体和大气流体是由六代不同代白云岩在多阶段事件中结晶形成的，这符合文献中不同的白云石化模型。一、中元古代灰岩，从浅水到深水台地，通过海洋和盆地流体的相互作用，通过用白云石替代成岩方解石而被白云石化（埋藏压实模型）。在卸压区，第一次填隙白云岩的形成代表了沉积-变质转变。在巴西亚诺-泛非造山运动期间，第二个白云石化阶段（构造模型）发生了生成白云岩，引发水力压裂，随后又在碎片边缘沉淀白云岩，从而形成白云质角砾岩。二次白云岩填隙样的沉淀与构造白云石化阶段和水力角砾化同时发生。在第三白云石化阶段（热对流模型），热液-花岗岩流体促进了鞍形白云岩的沉淀，填充小孔。随后，归因于热液-花岗岩和陨石流体的去白云石化过程（热对流/流星模型）诱导了方解石、石英、萤石和磷灰石的结晶，填充了白云质角砾岩中的孔洞。