The Clair Field is located 75km west of Shetland in water depths of up to 140 meters. It comprises a naturally fractured sandstone reservoir, which over the scale of the Clair Field made reservoir connectivity and compartmentalization risk key uncertainties for field development planning
The 206/8-13Y Clair Ridge appraisal well was located 8km from the existing Clair production platform and designed to confirm the next stage of development of the field
An opportunity was identified to instrument the well with a CaTS gauge at the time of final abandonment, thus converting it to a long-term monitoring asset. Observing for interference effects resulting from production or injection events on adjacent assets would demonstrate wide-scale reservoir connectivity
Expro Excellence
A Drill Stem Test (DST) was performed on the well using a permanent packer and tailpipe
On completion of the final pressure build up, a CaTS gauge was conveyed into the well throughtubing and hung off below a bridge plug set at the bottom of the tail pipe
The DST string was then recovered to surface and the well permanently abandoned in accordance with the applicable UK regulations
After installing a CaTS subsea receiver on the seabed, the rig departed the abandoned well location allowing the reservoir pressure and temperature data being transmitted from downhole to be collected at the receiver
Provides a unique wireless reservoir monitoring solution in a permanently abandoned subsea appraisal well
Value to Client
18 months of high-quality reservoir data was recovered from the permanently abandoned subsea appraisal well at low incremental well cost
The correlation of the reservoir pressure responses and trends between the Clair phase 1 platform and the Clair Ridge appraisal well provided clear evidence of reservoir connectivity
Cost effective Advanced Reservoir Testing in an abandoned subsea appraisal well provided high value data to steer the future development planning on Clair