Trillion Energy has confirmed the discovery of light oil at the Çetinkaya-1 (C-1) exploration well in south-east Türkiye, marking a significant development in the company’s regional exploration programme.
The C-1 well, situated in Block M47C3, C4 in Şırnak Province, encountered a 32.4-degree American Petroleum Institute (API) light oil within the Cretaceous Beloka and Mardin Group carbonates, reservoirs known for high-quality production across the region.
Located roughly 11 kilometres south-east of Türkiye’s largest onshore oil field, the Şehit Aybüke Yalçın field, the new discovery shares geological characteristics with the nearby producing reservoirs.
The well’s reservoir traits, including oil gravity, porosity and fracture-induced flow, reflect similarities to those observed in fields currently producing within the same carbonate formations.
Trillion Energy’s evaluation programme at the Çetinkaya-1 site incorporated detailed wireline logging, including gamma ray, dual laterolog resistivity and compensated density tools.
Data interpretation employed Archie’s equation to account for the specific formation conditions present in the C-1 well.
The well is positioned on the eastern flank of the North Lead structure near the estimated spill point, suggesting it may have intersected only a portion of a more extensive hydrocarbon column.
To further assess the resource potential, the company plans to drill a sidetrack, Çetinkaya-1ST, targeting the structural crest roughly 75 to 100 metres higher than the initial borehole.
This follow-up well is expected to intercept a thicker oil column and test zones that remain unexplored due to the premature cessation of drilling caused by loss of circulation at a depth of 2,455 metres.
Technical results from the current well indicate the presence of a fractured dolomitic reservoir with a gross interval of 76.6 metres and a net oil pay of 38 metres.
Fracture-adjusted measurements yielded a gross pay of approximately 40.6 metres and a net pay range of 36 to 38.5 metres.
The average effective porosity of the reservoir is reported at 5.5 per cent, while permeability is estimated between 5 and 50 millidarcies.
Water saturation levels average about 25 per cent. Within one highlighted seven-metre zone, porosity reached 8.1 per cent and water saturation dropped to 8 per cent, suggesting oil saturations exceeding 90 per cent.
The C-1 well’s reservoir primarily consists of dolomitic carbonate, consistent with regional productive analogues.
A hydrochloric acid stimulation successfully confirmed fracture permeability and yielded 32.4 API light oil, with a final oil cut measured at 36 per cent.
Despite these successful outcomes, the well penetrated only a fraction of the targeted 250 to 350-metre section, leaving more than 160 metres of potential reservoir untested.
Trillion Energy notes that several stacked pay zones across the Beloka and Derdere Formations indicate a multi-zone oil system in this area.
Zone A, which provides an estimated 13 metres of net pay, is yet to undergo testing, while deeper intervals toward total depth display improved reservoir quality.
The planned sidetrack will aim to evaluate these sections and verify the full potential of the structure.
The discovery extends Trillion Energy’s recent momentum in Türkiye, following its 2024 recompletion activities at the Akçakoca Platform within the SASB gas field.
The Çetinkaya-1 results reinforce the company’s growing exploration portfolio and underscore the promising nature of Şırnak Province as an emerging onshore oil region.
