Abstract
This presentation discusses the ACT4 SPARSE project, which aims to develop low-cost, long-term geophysical monitoring for gigatonne-scale CO₂ storage. The approach utilizes sparse, strategically placed nodes that integrate seismic, electromagnetic, gravity, and surface deformation data to ensure containment and conformance while reducing reliance on costly full-scale 3D monitoring. The project focuses on automated data processing, machine learning, and multi-method data integration to optimize monitoring efficiency. Ongoing field tests at sites like CaMI.FRS in Canada help refine the technology for practical deployment.