Monitoring of the Deep subsurface: Leakage pathways – understanding and monitoring of the mechanics of CO₂ storage

This blog was provided by Laurence Cowton whose attendace at the meeting was facilitated by the ECR Meeting Fund. If you would like to see the presentations from the meeting then click here.

On the 23rd October 2014, the UKCCSRC and the University of Bristol hosted a meeting on monitoring of the deep subsurface at the Engineer’s House in Bristol.  The conference was organised by Ciara O’Connor, UKCCSRC and Anna Stork, University of Bristol with the aim of increasing awareness of other researchers’ activities and hopefully increasing collaboration between groups.

The meeting was kicked off by John Marshall of Shell who gave us a useful insight into the way industry is tackling some of the difficulties associated with setting up and monitoring CCS projects in the UK. This was followed by Lisa Roach of the University of Leeds, who, despite only starting there a few weeks ago, introduced the monitoring methods currently in use at the Aquistore project, based at the Boundary Dam Power Station in Canada. Despite no CO₂ having been injected at the site, three seismic reflection surveys have been carried out, allowing important repeatability checks of the 4D seismics to be carried out. Thankfully for me (as you will see shortly!) her work showed that these surveys proved to be highly similar, allowing direct comparison between the surveys.

After a short coffee break there were three presentations on the physics of CO₂ reservoir and cap rocks, and the permeability and trapping mechanisms which these rocks facilitate by Angus Best (NOC), Dan Faulkner (University of Liverpool) and Sam Krevor (Imperial College London). Of particular interest to myself was an idea introduced in Dan Faulkner’s talk that the permeability of the cap rock might be increased without fracturing the rock simply (but counter intuitively)  by increasing the stresses on the system.

After an excellent lunch it was my turn to give a talk. As by far the most junior academic in the room (having only just finished the first year of my PhD) it was a great privilege to be able to present my work to such a group of distinguished academics. My work is currently focused on improving the vertical resolution of 4D seismic reflection surveys, and I presented some early results of my work showing how the volume of CO₂ in the top layer of the Sleipner project has changed with time. This transitioned well into Andy Chadwick’s (BGS) talk on potential fluid pathways in the overburden at sequestration sites like Sleipner.

After yet more coffee Tom Lynch (University of Leeds) talked about how the pressures changes in reservoir systems when producing and injecting were not equal and opposite, but could potentially cause fracture of the rocks if not considered carefully. The talks were then finished off by James Verdon (University of Bristol) who discussed induced seismicity and the impact that would be felt if induced seismicity were to be linked to a CCS site.

The meeting was closed with a discussion of the days topics facilitated by Andy Chadwick, and future research projects and grant proposals were discussed. This was followed by a well-deserved trip to the nearby pub where academic discussions continued.

Overall this was a highly enjoyable experience. This was the first time I had presented my work to a CCS orientated audience and the feedback I received was very useful and will no doubt lead to future avenues of research for myself. Thanks to the UKCCSRC for funding my travel to and from the event!