Accelerated & expanded drilling programme at BNG
Caspian Sunrise plc is accelerating and expanding its drilling program at the BNG Contract Area, with three additional deep wells planned for the Yelemes Deep structure, targeting Permian dolomite, anhydrite, and Carboniferous limestone reservoirs. The company also announced a new shallow well at the Airshagyl structure to evaluate a palaeochannel. Independent estimates indicate gross oil reserves at Yelemes of 33.3 MMbbl (28.0 MMbbl net to Caspian Sunrise), comprising 28.3 MMbbl C1 reserves and 4.9 MMbbl C2 reserves across the T1, P1, and C2m formations, though these are subject to GKZ approval and further data.
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Introduction
The board is pleased to update shareholders with encouraging progress at the Yelemes Deep structure on the BNG Contract Area, which has resulted in an accelerated and expanded drilling programme and also with news of a new shallow well to be drilled on BNG's Airshagyl structure.
Background
The licence at the Yelemes Deep structure was renewed at the end of December 2025 as an appraisal licence with the obligation to drill three deep wells before the end of 2027 to qualify to apply for a 25-year production licence.
Deep Well 803
The well, which had an original Planned Total Depth of 4,300 meters and from which oil was produced under test from the Lower Triassic sandstone reservoir at depths of between 3,349 and 3,380 meters, has now been deepened to 3,927 meters. On completion of a further 150 meters drilling casing will be set to a depth of 4,100 meters with the plan to perforate and test on cased-hole basis an interval of approximately 20 to 30 meters within the depth range of 3,927 to 3,977 meters. In addition, to seek to increase hydrocarbon production, the Company plans to perforate and test further intervals with aggregate thicknesses of approximately 8 to 12 meters within the depth range of 3,770 to 3,800 meters.
The interval drilled to date is within the Lower Permian P1 section and comprises a mixed evaporite-carbonate succession, including anhydrite, rock salt, gypsum and limestone, with sandstone present in the upper part of the logged section.
The planned deeper target interval has not yet been fully penetrated or tested. Accordingly, no flow from that planned target interval has yet been obtained.
Expanded drilling programme
On the basis of the encouraging results to date at Deep Well 803 three further deep wells are to be drilled on the Yelemes Deep structure with Deep Wells 701 and 707 expected to be spudded in July 2026.
Deep Well 701
Deep Well 701 is planned to be drilled approximately 140 meters from Deep Well 802 to a Planned Total Depth of 5,000 meters, targeting Permian dolomite and anhydrite intervals and Carboniferous limestone reservoirs.
The principal objectives of the well are to establish the lateral and vertical extent of the Lower Permian P1 reservoir, refine the position of the oil-water contact and assess the hydrocarbon potential of the Middle Carboniferous Moscowian C2m reservoir.
The Moscowian reservoir was previously encountered by Deep Well 801. Testing there over an interval between 4,638 and 4,657 meters produced oil and gas, with an oil flow rate of approximately 17 m³/day, equivalent to approximately 107 bopd.
Well 707
Well 707 is planned to be drilled to a Planned Total Depth of 3,500 meters, targeting the Lower Triassic T1 reservoir.
The well is planned to test a fault-related structural closure. Its principal objectives are to establish the lateral and vertical extent of the Lower Triassic reservoir, refine the position of the oil-water contact, and evaluate the hydrocarbon potential of the overlying Middle Jurassic section.
Deep Well 703
Deep Well 703 is planned to be drilled to a Planned Total Depth of 4,750 meters, targeting the Middle Carboniferous Moscowian C2m reservoir.
The well is planned approximately 2.2 kilometers north-east of Deep Well 801. Its principal objectives are to establish the lateral and vertical extent of the C2m reservoir, refine the position of the oil-water contact and obtain the technical information required to support a potential reclassification of reserves from category C2 to category C1 under the Kazakhstan reserves classification system.
The well will also evaluate the Lower Permian P1 reservoir. Testing of the P1 interval at Deep Well 802 between 3,889 and 3,890 meters produced oil at rates of 173 m³/day and 180 m³/day, equivalent to approximately 1,088 bopd and 1,132 bopd, through 9 mm and 12 mm chokes respectively.
The well is due to be spudded in H2 2026 as a rig becomes available on completion of either Deep Wells 701 or 707.
Airshagyl
Shallow Well E-Mz-55
Well E-Mz-55 is planned in the central part of the Airshagyl structure, approximately 7.3 kilometers north-west of Well Nsannovskaya-71.
The well will be drilled to a Planned Total Depth of 2,300 meters, targeting the Middle Jurassic J-I reservoir.
Seismic analysis has identified a clearly defined palaeochannel feature at depths of between approximately 1,950 and 1,990 meters.
The well is designed to evaluate the reservoir potential of the palaeochannel and the possible extension of the productive Middle Jurassic interval present at the neighbouring North-West Yelemes field.
Yelemes Field - Kazakhstan C1/C2 Oil Reserve Estimates
The Company has received reserve estimates calculation report for the Yelemes area, together with an exploration drilling program for deep wells planned for 2026. The report and the associated drilling program were prepared by an independent Kazakh project institute "SciRes" with recognised expertise in preparing reserves calculations and technical documentation under the methodology of the State Commission on Mineral Reserves of the Republic of Kazakhstan ("GKZ"). The calculation was prepared under the Kazakhstan statutory resource classification system. These reserve estimates have not yet been approved by the GKZ and remain subject to revision until additional data following deep drilling, logging and testing is available.
The estimate was calculated using the volumetric method based on mapped oil-bearing area, weighted average effective oil-saturated thickness, effective rock volume, porosity, oil saturation, recalculation coefficient, oil density and oil recovery factor.
The calculation indicates the following estimated gross oil reserves at Yelemes:
| | Gross | Net attributable to Caspian Sunrise | |||||
|---|---|---|---|---|---|---|---|
| Formation | C1 - reserves MMbbl | C2 - reserves MMbbl | (C1+C2) MMbbl | C1 - reserves MMbbl | C2 - reserves MMbbl | (C1+C2) MMbbl | Operator |
| T1 (Lower Triassic) | 17.0 | 0.0 | 17.0 | 16.8 | 0.0 | 16.8 | Caspian Sunrise |
| P1 (Lower Permian) | 10.4 | 0.6 | 11.0 | 10.3 | 0.6 | 10.9 | Caspian Sunrise |
| C2m (Middle Carboniferous Moscovian) | 0.9 | 4.3 | 5.2 | 0.9 | 4.3 | 5.1 | Caspian Sunrise |
| Total | 28.3 | 4.9 | 33.3 | 28.0 | 4.9 | 33.0 |
Notes:
- The reserve estimates were provided in tonnes, which have been converted to barrels using a conversion factor of 7.33 barrels per tonne has been applied.
- Caspian Sunrise has an economic interest in 99% of BNG, in which these assets are located
Under the Kazakhstan classification, C1 represents the higher-confidence portion of the technical estimate of reserves, while C2 represents an additional, less- well appraised statutory category of reserves.
These categories are not directly equivalent to SPE-PRMS 1P, 2P or 3P reserves, nor to SPE-PRMS Low, Best or High estimates.
It should be noted that these estimates require further work to be notified to a recognised standard, such as SPE-PRMS, before they can be classified as reserves under that framework. Once that work has been completed, the actual reserves in place may vary from these estimates.
Ms Danara Junussova, a member of the Society of Petroleum Engineers, has reviewed and approved the technical disclosures in this announcement.
This announcement has been posted to:
Definitions
| Bopd | Barrels of oil per day. |
| C1 reserves | are those quantities of petroleum which, by analysis of geosciences and engineering data, can be estimated with reasonable certainty to be commercially recoverable, from a given date forward, from known reservoirs and under defined economic conditions, operating methods, and government regulations. |
| C2 reserves | are those additional reserves which analysis of geosciences and engineering data indicate are less likely to be recovered than proved reserves but more certain to be recovered than possible reserves. It is equally likely that actual remaining quantities recovered will be greater than or less than the sum of the estimated proved plus probable reserves. |
| Reserves | Reserves are those quantities of petroleum anticipated to be commercially recoverable by application of development projects to known accumulations from a given date forward under defined economic conditions, operating methods and government regulations. |
| M³ | Metres cubed |
| MMbbl | Million barrels of oil. |
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