Investigating multiscale characterisation of porosity and permeability of Hellisheioi CO2 reservoir, Iceland to quantify storage capacity

Carbon Capture and Storage (CCS) is widely viewed as a valuable technique for reducing anthropogenic CO2 levels.

Conventional CCS involves CO2 injection into depleted hydrocarbon reservoirs or saline reservoirs, but Icelandic company Carbfix has developed technology involving CO2 injection into basalt reservoirs.

Unlike conventional CCS, where CO2 is stored as a superfluid, storage in basalt promotes CO2 to react with surrounding rock and mineralise to carbonate minerals. This eliminates the risk of CO2 leakage and ensures CO2 is permanently stored in a solid state.

Carbfix has been injecting CO2 since 2012, and the technology has proved viable: with 10,000T of CO2 sequestered and mineralising within two years of injection.

However, Carbfix are yet to quantify the storage capacity of the reservoir, and require further understanding of the fluid pathways present to determine future viability.

This project aims to quantify the storage capacity and petrophysical characteristics of Carbfix's Hellisheioi basalt reservoir through multiscale characterisation of the basalt's porosity and permeability.

This will involve structural geology field mapping, downhole data analysis and microstructural analysis (CT scanning, SEM scanning, optical microscopy, XRD).

Results will be compared to the geological characteristics at Hofn, Iceland, a natural analogue for the mineralisation process implemented by Carbfix