Well 6506/9-4 S was drilled by the semisubmersibleIsland Innovator to a depth of 4,580 m (15,026 ft) below the seabed. The aim was to reduce the uncertainty linked to the resource estimates for gas and condensate in the Jurassic Garn and Ile formations, and to improve understanding of the reservoir properties, including gas flow.
The well encountered a 67-m (220-ft) hydrocarbon column in Garn, with extensive data acquisition.
A side track then followed 0.8 km (0.5 mi) from the initial wellbore and 1.7 km (1.06 mi) from the discovery well: this was drilled to the location of potential future production wells, with a drillstem test flowing at a maximum (constrained) rate of 21 MMcf/d of gas and 547 b/d of condensate on a 22/64-in. choke for 24 hr, with no signs of depletion.
“We got positive information from the well and our estimates of the thicknesses and quality of the reservoirs have been confirmed. We also carried out a production test, which shows that the gas flows well from the reservoir,” said Dag Omre, managing director of Spirit Energy Norge.
Centrica discovered Fogelberg on the Haltenbanken in 2010. Updated calculations have narrowed the recoverable volume range to 40-90 MMboe of gas and condensate, against 23-94 MMboe.
“This drilling has considerably lifted the floor of the resource estimate,” Omre said, “thus reducing the risk and yielding a more robust project…
“We aim to submit a plan for development and operation to the authorities in 2019, which will allow for production to start in 2022.”
Development will most likely involve a seabed solution tied into Equinor’s Åsgard B platform, with the processed gas exported through the Åsgard Transport pipeline to Kårstø.
Condensate would be stored on Åsgard C for offtake by a tanker.
Currently Spirit is developing theOda oil field as a subsea tieback to Aker BP’s Ula platform in the southern Norwegian North Sea. Production here is due to start in 2019.