Impact of Mineralogy Variability on Acid Stimulation Design and Effectiveness in a Complex Carbonate Formation

Abstract This paper presents the results of a comprehensive study on the impact of mineralogy variability on acid stimulation design and effectiveness in a complex carbonate formation. Acid stimulation is commonly used to improve well productivity in carbonate reservoirs by enhancing permeability and removing damage near the wellbore. However, the effectiveness of acid treatment is highly sensitive to the heterogeneous nature of the reservoir, including variations in mineral composition, porosity, and texture. This study investigates the role of mineralogy variability in acid stimulation outcomes by analyzing a range of carbonate samples using X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques to characterize mineral content and formation texture. The paper covers a comprehensive analysis of post-stimulation flowback results and well performance comparison with offset wells, providing insights into how mineralogy variations can lead to discrepancies in acid stimulation efficiency. A significant finding of this study is the impact of clay minerals on acidizing treatments, which can reduce acid penetration and cause undesirable reactions, such as clay swelling or precipitation, leading to decreased well performance. The study also highlights the benefits of incorporating advanced technologies such as Distributed Temperature Sensing (DTS), which helps optimize acid distribution and evaluate acid flow in real-time, thus improving treatment outcomes and reducing operational risks. This work demonstrates the importance integrating geoscience, and engineering data to improve acid stimulation design and optimize treatment effectiveness in heterogeneous carbonate formations. The findings underscore the need for customized acidizing strategies based on detailed mineralogy characterizations to enhance well productivity and reduce costs associated with ineffective stimulation. By identifying the root causes of well performance discrepancies and suggesting more efficient treatment strategies, this study provides valuable insights for operators working in complex carbonate systems.