CO2 Storage Complex in Shallow Waters of Campos Basin, Brazil: Capacity, Uncertainty and Risk Analysis of a Deep Saline Formation

Abstract The role of Carbon Capture, Use, and Storage (CCUS) in reducing greenhouse gas emissions is crucial for achieving global climate targets. Brazil, as a significant emitter, is actively pursuing CCUS projects and the state of Rio de Janeiro, with its high emissions of industrial activities, presents an opportunity for establishing a CCUS hub. The potential storage reservoir, São Tomé Deep Saline Formation, located in the Campos Basin, offers favorable characteristics for CO2 storage. This srtdy aims to estimate the CO2 storage capacity, perform uncertainty analysis, and comprehensive risk assessments for the Sao Tome reservoir. The methodology involves mapping potential storage reservoirs, 3D geological modeling, and flow simulation to evaluate injectivity, storage potential, containment safety, and monitoring strategies. The results demonstrate a storage capacity of approximately 1 Gt of CO2, injectivity of 1.5 MMt C02/yr/well, and low leakage risk. However, further evaluation is required, including petrophysical characterization and geomechanical data. The proposal includes drilling a new well to acquire additional information and support more robust modeling. The establishment of a CCUS hub in Rio de Janeiro would bring economic, social, and environmental benefits, attracting companies seeking environmentally friendly solutions and facilitating the development of the shallow-water industry. To achieve the Net Zero Scenario by 2050, CCUS plays a crucial role in emissions reduction, and the Sao Tome reservoir presents significant potential for CO2 storage. Continued evaluation and data acquisition are necessary to ensure the feasibility of large-scale CO2 injection projects. The establishment of a CCUS hub in Rio de Janeiro would position the region as a center of environmental responsibility and attract investment and innovation in the energy sector.