Identification of potential CO2 storage zones in the Deccan Volcanic Province using multi-criteria decision-making approaches

India, the third-largest contributor to global CO₂ emissions (∼8 %), faces significant challenges in implementing large-scale geological carbon storage (GCS) projects. While geological suitability is crucial, socio-economic factors also influence feasibility, especially in a densely populated country like India. Additionally, public awareness of carbon capture, and storage (CCS) remains limited, making safety a key consideration. Basalt-based GCS offers permanent CO₂ mineralization, providing a secure storage solution. The Deccan Volcanic Province (DVP), spanning ∼500,000 km², presents a significant opportunity for gigaton-scale CO₂ storage. While previous studies have demonstrated the proof-of-concept for CO₂ storage in the DVP, no attempt has been made to characterize specific sites for pilot-scale projects. This study employs a Multi-Criteria Decision-Making approach, integrating Analytic Hierarchy Process (AHP) and Fuzzy-AHP (FAHP) to assess CCS site suitability in the DVP. The efficiency of the AHP and FAHP models were further verified using Monte Carlo FAHP technique. Nine geological, hydrological, and infrastructural factors were analyzed to generate suitability maps. The study identifies the Saurashtra region in Gujarat, northern Madhya Pradesh, and the Mumbai-Pune-Nashik corridor as highly suitable zones. Sensitivity analysis highlights ''distance to faults'' and ''basalt thickness'' as most influential factors, with FAHP providing more robust site characterization. While these findings provide a framework for narrowing down potential CCS sites in this largely unexplored region, further investigations into geochemical properties, host rock mechanical strength, and seismic risks are essential. Finally, estimated CO₂ storage potential in suitable areas suggests substantial potential, enabling long-term storage and reducing the source-to-sink distance for major emitting regions.