Distributed seismic monitoring for geological carbon sequestration

The overall goal of the Project is to develop Distributed Acoustic Sensing (DAS) as a standalone technology or in combination with other technologies to serve as an Early Warning System for identifying risks during geological CO₂ injection and storage.

Technical content:
In order to accelerate the development of DAS technology for CCS applications there is a need for open research and verification of the technology. This can be achieved by securing leading research institutes full access to the monitoring data and interpretations.

A small-scale field test will be performed to compare various near-surface deployment designs to identify the most efficient geometry of the fibreoptic sensor cable deployment (grid, star, spiral, …).

Full scale testing will be carried out in conjunction with CO₂ injection at CaMI FSR, Canada, a world-leading CO₂ storage research station. In addition will the project have access to the CCS test site at Gundih gas field, Indonesia.

Technical advantages:
The most widely used methods as of today for monitoring of CO₂ injection into geological storage formations are by surveys employing active seismic or by measuring the passive seismic waves generated in the well and formation. The waves are detected by marine hydrophones or geophones placed on the ground surface or seafloor. Geophones may also be placed along a string in the wellbore, in a technique known as vertical seismic profiling (VSP).

An alternative technology has recently emerged known as Distributed Acoustic Sensing (DAS). DAS is a passive fibre optic sensor technology with the ability to detect acoustic fields anywhere along the fibre with a very tight spatial resolution. Conventional geophones offer better detection capabilities than DAS in terms of signal to noise ratio and the ability to detect the directionality of the seismic wave. DAS systems on the other hand offer spatially continuous data over long distances. Furthermore, the fact that the sensing element in DAS is an ordinary optical fibre facilitates low infrastructure and deployment costs; in some cases, pre-existing fibre installed for other reason may even be used.

R&D challenges:
To develop carbon specific storage applications for DAS by addressing challenges such as optimisation of cable design and installation, and data interpretation and validation.

Results to date:
Planned kick-off meeting in September 2016
Industry on board, re-planned according to revised budget??