Analysis of Surface Movement through Conceptual and Coupled Flow-Geomechanics Models an Example of Surface Monitoring Assessment for CCS Project

Abstract

Monitoring of geological CO2 storage sites is crucial for the widespread deployment of this technology to be accepted as a reliable method of reducing CO2 emissions worldwide. The SENSE project aims to develop reliable, continuous and cost-effective monitoring based on ground motion detection combined with modelling and geomechanical inversion, using new technological developments, data processing optimization and interpretation algorithms. In this context, we present a methodology based on coupled flow/geomechanical simulations which, from the uncertainty on the subsurface properties and uncertainties on the measurements, can reproduce the measurements from different surface monitoring tools. By carrying out an uncertainty study on simulations results and taking into account the advantages and disadvantages of each of these tools, a monitoring strategy can be designed such that the tools will record potential displacements at the most sensitive periods and locations, taking into account their respective accuracies. If surface displacements are measurable and sufficiently sensitive to subsurface properties then this kind of monitoring will help to better constrain subsurface properties and possibly subsurface behavior such as plume migration, pressure propagation, and storage capacity. This methodology is applied to conceptual models in order to identify which conditions induce different surface displacements and thus may require specific surface monitoring strategy.