18 August 2025

Pantheon Resources plc

Dubhe-1 Appraisal Well Exceeds Pre-Drill Estimates in Target Reservoir

Confirms Additional Prospective Resources in Secondary Objectives

Pantheon Resources plc (AIM:PANR, OTCQX: PTHRF) ("Pantheon" or the "Company"), the oil and gas company developing the Kodiak and Ahpun oil fields near pipeline and transportation infrastructure on Alaska's North Slope, today announces results from the Dubhe-1 appraisal well.

The primary target of Dubhe-1 was the topset horizon (SMD-B), appraising the already discovered resource. Additionally, the well was designed to encounter three further exploration horizons (Prince Creek, SMD-C and the Slope Fan System), none of which have previously had any resource estimate attributed to them. Logs confirm additional prospective resource upside in these horizons.

Key Points

·    The Dubhe-1 pilot hole was successfully drilled, logged and cored to a total measured depth ("MD") of 12,833 ft, equivalent to 8,699 ft true vertical depth ("TVD")

·     Analysis of the thickness and quality of the primary target topset confirms that the SMD-B has exceeded the upside pre-drill expectations. The gross thickness of the hydrocarbon column in this interval was measured at 565 ft true vertical thickness ("TVT"); exceeding pre-drill expectations by 26%

·     Dubhe-1 also encountered additional hydrocarbon bearing horizons in two of the exploration targets; the SMD-C and two Slope Fans

·    The Company intends to drill, and subsequently flow test the planned sidetrack lateral in the SMD-B horizon to refine the production well type curve 

Dubhe-1 Well: Phase 1 Outcome

The first phase of the Dubhe-1 well programme consisted of a deviated pilot hole to gather cores and logs to select the optimum landing zone for a subsequent lateral sidetrack in the primary SMD-B zone. The well successfully reached the planned TVD and achieved all planned target reservoir penetrations - both primary and exploration objectives.

Additional hydrocarbon bearing zones were encountered in the SMD-C and two Slope Fans.  These horizons were not included in the Ahpun estimated contingent resources of 282 million barrels and 804 billion cubic feet, prepared by Cawley Gillespie & Associates and therefore these resources represent material upside potential as co-development opportunities alongside the established Ahpun SMD-B primary reservoir. 

Details of Appraisal Analysis

Preliminary analysis indicates that Dubhe-1 has intersected multiple hydrocarbon bearing horizons over approximately 2,143 ft MD (1,085 ft TVT). In addition to the primary SMD-B objective of the well, multiple reservoirs were penetrated in this overall section consisting of interbedded sands and shales.

All intervals were logged with a full suite of Logging While Drilling ("LWD") tools and Volatiles Analysis Service ("VAS") of both sealed and unsealed cuttings samples. A 90 ft core, with 100% recovery, was taken from 11,732 - 11,823 ft MD (8,142 - 8,187 ft TVD) within SMD-B interval. In addition, sidewall cores were gathered to aid with log calibration.

Integrated analysis indicates the following hydrocarbon bearing zones within the Campanian interval:

In addition to these results, hydrocarbons were also identified in the Maastrichtian interval (Prince Creek and Upper Schrader Bluff Topsets 1 and 3) with a gross thickness of 1,158 ft TVT, in line with those same horizons encountered in Megrez-1. Preliminary analysis indicates similar reservoir properties and the results will be combined with the data from Megrez-1 for further technical evaluation and potential associated long term development planning if warranted.

Forward Plans

The Company is presently finalising the optimum location to position the lateral section of the well within this thick 565ft TVT section of SMD-B horizon. Drilling of this lateral is expected to commence over the coming days.  In addition to the logs, cores, cuttings and other data collected in the pilot hole, data gathered from the drilling of this horizontal lateral will be further integrated into the analysis.

At the same time, the Company is analysing data to optimise the design of hydraulic stimulation plans in the lateral. The Company is also tendering several service providers for these operations and a decision is expected to be made on these matters during the next two months. The Company will issue further guidance on this plan of operations when available.

The Company will be evaluating the large data set gathered from this well and previous wells penetrating these horizons that includes whole core and sidewall cores, VAS analysis of cuttings, LWD and wireline logs, seismic check shots to calibrate the proprietary 3D survey and reservoir fluid analysis ("PVT"). These analyses will be used to refine the dynamic reservoir model and design permanent production facilities as the Company's capital programme transitions to Ahpun field development. The Company will host a webinar on 9^th September, 2025 to share the results of the Dubhe-1 drilling operation and preliminary insights into the scale of additional prospective resources encountered in the SMD-C and the Slope Fans.

Erich Krumanocker, Chief Development Officer, said:

"We are delighted to announce the Dubhe-1 pilot hole results as a success. The well confirms the presence and quality of the oil and gas reservoirs in the Ahpun field, exceeding our pre-drill expectations. We are now transitioning toward field development planning in support of capital efficient commercial production. The upside presented by the SMD-C and Slope Fan zones highlights the enormous potential in our portfolio."

For further information, please contact:

Corporate Contact

Pantheon Resources plc
Justin Hondris
[email protected]

Nominated Adviser and Joint Broker
Canaccord Genuity Limited
Henry Fitzgerald-O'Connor, James Asensio, Charlie Hammond
+44 20 7523 8000

Oak Securities - Joint broker

Jerry Keen, Nick Pryce

+44 20 39733678

Public Relations Contact
BlytheRay
Tim Blythe, Megan Ray, Matthew Bowld
+44 20 7138 3204

Investor Relations Contact - USA
MZ Group
Lucas Zimmerman, Ian Scargill
+1 949 259 4987
[email protected]

In accordance with the AIM Rules - Note for Mining and Oil & Gas Companies - June 2009, the information contained in this announcement has been reviewed and signed off by David Hobbs, a qualified Petroleum Engineer and a member of the Society of Petroleum Engineers, who has 40 years' relevant experience within the sector.

The information contained within this Announcement is deemed by Pantheon Resources PLC to constitute inside information as stipulated under the Market Abuse Regulation (EU) No. 596/2014 as it forms part of UK law by virtue of the European Union (Withdrawal) Act 2018 ("MAR").

About Pantheon Resources

Pantheon Resources plc is an AIM listed Oil & Gas company focused on developing its 100% owned Ahpun and Kodiak fields located on State of Alaska land on the North Slope, onshore USA. Independently certified best estimate contingent recoverable resources attributable to these projects currently total c. 1.6 billion barrels of ANS crude and 6.6 Tcf of associated natural gas. The Company owns 100% working interest in c. 259,000 acres.

Pantheon's stated objective is to demonstrate sustainable market recognition of a value of $5-$10/bbl of recoverable resources by end 2028. This is based on bringing the Ahpun field forward to FID and producing into the TAPS main oil line (ANS crude) by the end of 2028. The Gas Sales Precedent Agreement signed with AGDC provides the potential for Pantheon's natural gas to be produced into the proposed 807 mile pipeline from the North Slope to Southcentral Alaska during 2029. Once the Company achieves financial self-sufficiency, it will apply the resultant cashflows to support the FID on the Kodiak field planned, subject to regulatory approvals, targeted by the end of 2028 or early 2029.

A major differentiator to other ANS projects is the close proximity to existing roads and pipelines which offers a significant competitive advantage to Pantheon, allowing for shorter development timeframes, materially lower infrastructure costs and the ability to support the development with a significantly lower pre-cashflow funding requirement than is typical in Alaska. Furthermore, the low CO2 content of the associated gas allows export into the planned natural gas pipeline from the North Slope to Southcentral Alaska without significant pre-treatment.

The Company's project portfolio has been endorsed by world renowned experts. Netherland, Sewell & Associates estimate a 2C contingent recoverable resource in the Kodiak project that total 1,208 mmbbl of ANS crude and 5,396 bcf of natural gas. Cawley Gillespie & Associates estimate 2C contingent recoverable resources for Ahpun's western topset horizons at 282 mmbbl of ANS crude and 803 bcf of natural gas. Lee Keeling & Associates estimated possible reserves and 2C contingent recoverable resources totalling 79 mmbbl of ANS crude and 424 bcf natural gas.

For more information visit www.pantheonresources.com.