The carbonate rock is composed of dolomite, calcite, microcrystalline chert, goethite, calcium sulfate, and pyrobitumen. The porous medium of the carbonate reservoir displays significant variations in water saturation at notably low levels. The high-risk nature of the reservoir is primarily characterized by elevated temperature and pressure conditions, stress levels, abundant presence of H2S and CO2 gases, intense anisotropy; as well as fractures development and mineral sensitivity. This type of reservoir is highly susceptible to damage caused by leakage induced by factors such as water flow rate, salt content, alkalinity level, and stress conditions. Furthermore, it may lead to catastrophic accidents. Drawing from a comprehensive mineral description and analysis of reservoir rock sensitivity, this study elucidates the specific mechanisms accountable for formation damage in carbonate formations. These damages stem primarily from the interactions between sensitive minerals and alkaline working fluids or acidic gases, such as H2S and CO2. Elevated concentrations of these gases can disrupt the natural occurrence and microstructure of minerals, leading to particle movement and plugging within the formation’s flow matrix, consequently impacting overall reservoir productivity. To address this challenge, diverse prevention and control strategies have been proposed to mitigate such damage during drilling operations, well killing procedures, and reservoir renovation activities. These strategies are tailored to consider the distinctive characteristics of carbonate formations, particularly their susceptibility to alkaline or acidic fluids with an aim to minimize disruption of the formation’s inherent mineralogy and microstructure. The findings presented not only contribute significantly towards controlling formation damage in highly H2S-rich carbonate reservoirs but also establish a robust theoretical foundation for studying and applying development technologies in gas reservoirs characterized by high concentrations of H2S. By comprehending the specific mechanisms underlying formation damage, researchers and engineers can devise more effective strategies for preventing and managing such issues, ultimately enhancing gas reservoir productivity and longevity.
