An Object-Based Approach Simulating Early Carbonate Diagenesis

Abstract The early diagenetic processes that occur in carbonate reservoirs play a pivotal role in shaping their porosity and permeability, ultimately influencing their suitability for hydrocarbon storage and CO2 sequestration. As the foundation for subsequent mechanical and chemical compaction, early diagenesis sets the stage for the long-term evolution of these reservoirs. Therefore, accurately modeling these complex diagenetic processes is crucial for predicting the quality of carbonate reservoirs and optimizing assessments of their CO2 storage capacity. To address this challenge, we have developed a groundbreaking object-based method, paired with an intuitive Graphical User Interface (GUI), designed to simulate the intricate processes of early carbonate diagenesis. This integrated approach situates diagenetic processes within a comprehensive stratigraphic and climatic framework, accounting for a range of key reactions that control the evolution of carbonate reservoirs. These reactions include mineral dissolution, cementation, precipitation, and stabilization, which are simulated across four distinct diagenetic zones: the vadose zone, meteoric phreatic zone, marine phreatic zone, and mixing zones. Characteristic of a carbonate ramp, these zones are critical in determining the overall diagenetic trajectory of the reservoir. To ensure the accuracy of our simulations, reaction rates are calculated using advanced reactive transport modeling techniques, which are rigorously validated against empirical field data. By leveraging this innovative approach, we aim to provide a more nuanced understanding of the complex interplay between diagenetic processes, stratigraphy, and climate, ultimately enhancing our ability to predict and optimize the quality of carbonate reservoirs for a range of applications, including CO2 storage and hydrocarbon production.