“…The potential for secondary mineral precipitates to irreversibly damage well productivity and reduce the overall extraction efficiency is a well-recognized concern. ,− Oxidative and/or acidic dissolution of Fe(II)-bearing phases ( e.g. , pyrite, siderite, Fe(II) in carbonate minerals, and Fe(II) bound directly to organic matter) in shales is triggered by acid injection. , Pyrite, in particular, readily oxidizes to Fe(III) and, depending on the solution pH, rapidly precipitates as Fe (oxyhydr)oxides. ,,, Because solution pH has a strong influence on the rate of Fe(II) oxidation, the carbonate content of the rock can also influence this process.…”