North Sea Discovery Serenity

27th September 2022

The Serenity field was discovered by well 13/23c-10, drilled by i3 (100% WI) in late 2019. The well encountered a 20ft thick oil-bearing sand (11ft true vertical thickeness, TVT) unit at the top of the Lower Cretaceous Captain sequence. The reservoir quality was high, with porosities averaging 24.5% and oil samples, recovered by wireline, having an API of 31.5°, suggesting that they are very similar to the oil in the neighbouring Tain and Blake fields. The Serenity reservoir is a pinch-out of the Captain sands against the southern margin of the Halibut Horst, analogous to the Tain and Blake Flank. The sand has 11ft TVT at the 13/23c-10 well and thickens toward the west reaching 115ft TVT in the 13/23a-7z well immediately adjacent to Serenity's western closure.

The Blake, Tain and Serenity fields share a common reservoir and OWC. Their depositional history and reservoir charge have been modelled by i3. The model has been confirmed by the pressure and fluid composition data from the Serenity well.

Hence the re-development of the Blake field, development of the Tain field and appraisal / development of Serenity share common attributes and may be linked, depending on optimal use of infrastructure and commercial agreement between the parties.

The reserves already discovered at Serenity represent the opportunity for a commercially attractive tie-back to the planned development at Tain (operated by RSRUK and subject to development approval) with recoveries of approximately 8.5 to 20 MMbbls. If further appraisal confirms the sand deposition and connectivity model, then oil in place would be circa 197MMbbls and a stand alone full field development would generate recoveries of 100 MMbbls or more. With successful additional appraisal, alternate development options for Serenity could include re-deployment of an existing North Sea FPSO or tie-back to alternate existing infrastructure. Planning and permitting for the well is ongoing with the well Operator appointed.

For visualisations and a video go to https://i3.energy/operations/uk-north-sea/serenity/