Pantheon Resources PLC is testing production at the Alkaid #2 well on Alaska’s North Slope, south of Prudhoe Bay and Kuparuk oil fields, and has updated its North Slope reserves using a new detailed reservoir model. The model estimates that Pantheon’s reservoirs contain 17.8-billion bbl net oil in place (OIP) versus initial estimates of 23-billion bbl OIP. With additional drilling data, modelling estimates may increase in the future.
Pantheon used a coiled tubing unit (CTU) to remediate a sand blockage inside the horizontal production liner. The CTU cleared most, but not all, of the blockage and flow testing has resumed. The well is still early in its cleanup phase and definitive assessment of commerciality cannot be made until flow-testing operations have concluded.
A static and dynamic reservoir model of Pantheon's subsurface geological projects has been completed over three project areas in four distinct oil reservoirs which encompass Alkaid, the Slope Fan System, the Shelf Margin Deltaic (SMD), and the Basin Floor Fan system. The model updated expected reserves and will aid in seismic interpretation, drilling and completion methodologies, and improvements in drilling and recoveries.
Pantheon believes that the reservoir improves in quality to the north of Theta West #1 both within and outside its current leasehold, which is the primary reason Pantheon bid on new acreage in that area in the November 2022 Alaska lease sale.
The recently acquired acreage and its resource potential is not considered in the reservoir model nor in Pantheon’s current estimates. The next project phase will address these differences along with developing a dynamic development model to predict overall recoveries.
In addition to modelling OIP, individual well recoveries were modelled for Alkaid, Theta West, and Talitha reservoirs over a 1-mile lateral length with 30-years recovery of 1.1 MMbo, 1.5 MMbo, and 1.2 MMbo, respectively. Longer lateral lengths are expected to yield higher production volumes. Pantheon's development plan is based on optimum lateral lengths of 8,000-10,000 ft.
Pantheon estimates a recovery factor of 10%. Based on the model’s OIP, expected recoverable oil is more than 1 billion bbl.
Pantheon has 100% working interest in its North Slope assets.
Alex Procyk | Upstream Editor
Alex Procyk is Upstream Editor at Oil & Gas Journal. He has also served as a principal technical professional at Halliburton and as a completion engineer at ConocoPhillips. He holds a BS in chemistry (1987) from Kent State University and a PhD in chemistry (1992) from Carnegie Mellon University. He is a member of the Society of Petroleum Engineers (SPE).