Storage: saline aquifers, depleted oil and gas fields

Storage options like saline aquifers and depleted oil and gas fields are underground reservoirs used to store substances such as carbon dioxide or other fluids. Saline aquifers are porous rock formations soaked with salty water, capable of holding gases safely underground. Depleted oil and gas fields are former energy reservoirs where extraction is complete; they have sealed layers that prevent leakage. These sites are attractive because their geology provides secure containment, making them suitable for long-term storage of greenhouse gases or other materials, helping reduce environmental impacts while utilizing existing subsurface infrastructure.