Initial results of a pilot project for sub-seabed basalt storage of carbon dioxide on the Reykjanes Ridge

To meet temperature goals that limit warming to well below 2 °C requires the removal of hundreds of billions of tonnes of CO₂ from the atmosphere over the course of this century. Effective Carbon Dioxide Removal (CDR) methodologies will be required to reduce net emissions in the near term, counterbalance residual CO₂ emissions to achieve net-zero in the medium term, and contribute to net-negative emissions in the longer term – all of this in a sustainable and safe manner. This paper summarizes the research objectives and selected initial results of a collaborative project to assess CO₂ storage in the upper ocean crust south of Iceland.

The AIMS³ project (www.aims3.cdrmare.de) will deliver new insights, monitoring tools and feasibility assessments for CO₂ storage in young, reactive basalts with little sedimentary cover. Along the flank of the Mid-Atlantic Ridge, we have done geophysical surveys and drilled a transect of boreholes in order to identify fluid migration in the upper ocean crust. Both in situ heat flow and geochemical signatures provide irrefutable evidence for such transport, which will help distributing injected CO₂ in future experiments.

In parallel, our project also has mineralization experiments to assess optimal conditions for injection dissolved, liquid, or supercritical CO₂), numerical modelling for upscaling our results from seagoing work, and development of cost-effective sensors and smart robotic landers for long-term monitoring of the vicinity of the boreholes. We outline the rationale of AIMS³, provide an overview of the activities, and highlight some of the expedition results, with the goal to stimulate communication and collaboration.