Years of subsurface studies in Ghana’s Voltaian Basin are advancing towards a major milestone, as the Ghana National Petroleum Corporation (GNPC) and its exploration subsidiary, GNPC Explorco, intensify preparations to drill the TUA-1X exploratory well at Chegu in the Mion District of the Northern Region.
The proposed well will take the exploration programme from seismic data and geological interpretation into the subsurface, providing new information to test years of technical work and help determine the direction of further exploration across the Basin. It marks the first exploratory well to be drilled anywhere in the Voltaian Basin since 1974.
Management of GNPC and GNPC Explorco visited the proposed well location to review progress and the immediate work programme ahead of drilling. Physical preparations will begin with the construction of a 13.5-kilometre access road to Chegu and a rig pad at the proposed well location, alongside other site works required for the safe mobilisation and arrival of the drilling rig.
“The Next Step Is Site Preparation”
GNPC Explorco Managing Director Sam Opoku-Arthur said the move to site preparation follows extensive subsurface work to identify and mature the drilling location. “The next step for us, after all the subsurface work that we did, is to start the construction of the access road and the rig pad and ensure the safe arrival of the rig,” he said.
TUA 1X Well Project Manager at GNPC Explorco, Joseph Lartey, said engineering design is complete, with the next phase covering the access road, preparation of the well location, and development of the base camp.
GNPC Chief Executive Kwame Ntow Amoah described the move towards TUA 1X as the culmination of years of work and consistent with GNPC’s historic role in taking on exploration risk to open new areas for investment. Drawing parallels with GNPC’s early exploration work offshore Ghana, Mr Ntow Amoah said the Corporation was again taking the lead in de-risking a frontier area where investor appetite has historically been limited. “We are taking the lead this time to establish GNPC as the pioneer in opening up the Voltaian Basin,” he said.
A Basin With 11 Billion Barrels in Prospective Resources
Covering approximately 103,000 square kilometres — nearly 40 per cent of Ghana’s landmass and larger than the country’s combined offshore acreage — the Voltaian Basin is Ghana’s largest sedimentary basin. It spans parts of the Northern, Savannah, and other regions, and is one of West Africa’s largest unexplored basins.
GNPC estimates the basin could contain more than 11 billion barrels of oil equivalent in prospective resources, although the figure remains subject to confirmation through exploration. Deputy Chief Executive Hamis Ussif has described the basin as a strategic opportunity for Ghana’s energy future. “By very conservative estimates, this can unlock over 11 billion barrels of oil equivalent. The potential is very huge and GNPC is looking for partners to at the right time unlock resources that exist in this basin,” he said.
The Petroleum Commission’s Chief Executive, Emeafa Hardcastle, has said preliminary assessments of the basin have revealed encouraging petroleum potential and evidence of an active petroleum system, boosting confidence in its commercial prospects.
Decades of Exploration History
Exploration activity in the Voltaian Basin dates back to the 1950s and 1960s, when Soviet geologists under the Zarubezhgeologia, in collaboration with the Geological Survey Department, drilled eleven deep boreholes across locations including Tibagona, Tamale, Damongo, Larabanga, Nasia, Yendi, Buipe, Kintampo, Kete-Krachi, Prang, and Wulasi — reaching depths of up to 750 metres and encountering traces of oil and gas in some boreholes.
In 1977, Shell Exploration and Production Company (Ghana) Ltd. completed the Premuase-1 well in the southern part of the basin, drilled to a depth of about 1,167 metres. It was an unsuccessful wildcat well, and no further wells have been drilled in the basin since.
Serious interest in the basin resurfaced in 2005, with support from the European Union and the Minerals Commission. Since then, GNPC has invested over $160 million in seismic data acquisition, completing four phases of 2D seismic acquisition and further technical studies across the Basin, covering close to 500 communities. The basin now has 2D seismic data coverage of about 6,025 line-kilometres.
“Despite the basin’s long history of exploration interest, no wells have been drilled there since 1977, making TUA-1X a critical test of decades of geological and geophysical work”.
Optimism Tempered With Realism
Management was clear that moving towards drilling should not be interpreted as confirmation that oil or gas has already been discovered. Deputy Chief Executive Hamis Ussif, responsible for Finance, Commercial, and Administration, said an exploratory well remains valuable whether it encounters hydrocarbons. “You may hit your target, which is to find oil or gas, or you may not find oil or gas, but you still find data that will be useful for you going forward,” he stated. Ussif also said funding had been provided beyond the current year to support the drilling programme and related activities.
GNPC Chief Executive Kwame Ntow Amoah reinforced the point. “An exploratory well does not mean oil or gas has already been found,” he said, describing it instead as the step needed to establish whether hydrocarbons exist and whether any discovery could eventually be developed commercially.
A successful TUA 1X well would provide significant new subsurface information that could be integrated with seismic data already acquired and further improve understanding of the Basin’s petroleum potential. The data obtained will allow GNPC and GNPC Explorco to compare existing geological interpretations with actual subsurface conditions and inform decisions on subsequent exploration activity across the Basin.
Engaging Traditional Authorities and Host Communities
Ahead of the site visit, the delegation called on the Chegu Naa, Naa Andani Iddrisu, to update him on the work ahead and reaffirm continued engagement with the immediate host community. Naa Andani Iddrisu welcomed the progress made and emphasised openness, mutual respect, and continued collaboration as activities progress.
The Chegu engagement followed an earlier meeting with the Regent of Dagbon, Kampakuya-Naa Yakubu Abukari II, at the Gbewaa Palace in Yendi, where the traditional leadership was briefed on progress in the Basin and preparations for the next phase of exploration. The Regent reaffirmed Dagbon’s support for the exploration programme but pressed for continued consultation. “Partners are not informed after the fact. They are engaged before,” he said, calling for transparent communication, environmental responsibility and meaningful local participation as activity in the Basin increases.
GNPC’s engagement with Dagbon traces back to 2017, when it held discussions with the late Ya-Na Abukari Mahama II while he was Yoo-Naa of Savelugu. The delegation renewed condolences to the Dagbon royal family and people following the Ya-Na’s death.
The Member of Parliament for Mion, Misbahu Mahama Adams, and District Chief Executive Azindow Hamza Moabaly also reaffirmed their support for the programme and pledged continued collaboration with GNPC and GNPC Explorco.
Alongside the exploration work, the GNPC Foundation is running needs assessments in Mion, Karaga, Gushegu, Tolon, Zabzugu and Bimbila to identify local priorities in water, healthcare, education, sanitation and livelihoods. Ntow Amoah also said GNPC had awarded 297 scholarships to students at the University for Development Studies and Tamale Technical University as part of its support for communities in northern Ghana.
A Broader Strategy to Revive Ghana’s Upstream Sector
The TUA-1X well comes amid a broader government strategy to revive Ghana’s upstream petroleum sector after years of declining crude oil production. Production has nearly halved from 71.4 million barrels in 2019 to about 36 million barrels in 2025, raising concerns over the long-term sustainability of petroleum revenues. The government has secured more than $3.5 billion in fresh commitments from partners in the Jubilee and Offshore Cape Three Points (OCTP) fields, and multiple operators — including Eni, Tullow, Planet One, AMNI, and OPCO — have offshore drilling campaigns scheduled for 2026–2027.
President John Dramani Mahama announced in June 2026 that Explorco was poised to begin onshore drilling in the Voltaian Basin before the end of the year, describing it as part of a broader vision to build “an energy sector that is productive, competitive, resilient, and globally relevant”.
The government’s “Accra Reset” agenda seeks to reposition Ghana from a nation that primarily exports raw materials to one that processes, manufactures, refines, and creates value within its own borders. “The future belongs to nations that refine, manufacture, and export finished products,” President Mahama said.
Timeline Pressures and Industry Scrutiny
The project has faced repeated delays. Explorco had told an investor briefing in April 2025 that it expected to spud the well in the first quarter of 2026, but the timeline has since slipped. Finance Minister Dr Cassiel Ato Forson said in his 2026 Mid-Year Fiscal Policy Review that GNPC-Explorco remained on course to commence exploratory drilling during the fourth quarter of 2026. The Petroleum Commission’s CEO, Emeafa Hardcastle, has projected a window between the fourth quarter of 2026 and the first quarter of 2027.
Industry observers have expressed concern over the shifting timelines. Kodzo Yoatse, Policy Lead for Oil and Conventional Energy at the Africa Centre for Energy Policy (ACEP), said repeated revisions of the drilling timetable have weakened confidence in the project. “GNPC has not given us anything to instil confidence about the Voltaian Basin’s prospects. Even the timeline for drilling keeps shifting. The Corporation has spent over $120 million on that basin over the years with nothing concrete to show,” he said.
A Transformative Opportunity
Despite the delays and the inherent risks of frontier exploration, the potential stakes are enormous. A major onshore discovery would diversify Ghana’s energy sources, reduce reliance on imports, attract significant foreign direct investment, create jobs, and increase government revenue through taxes and royalties.
The Voltaian Basin spans several regions with limited large-scale mineral resources, and successful exploration could stimulate economic activity, create jobs and broaden opportunities beyond the country’s traditional mining enclaves.
With years of seismic acquisition and geological studies now behind the programme, the immediate focus shifts to constructing the access road, rig pad, base camp, and associated site-preparation works ahead of mobilisation for exploratory drilling. Whatever the outcome of TUA-1X, the information obtained from the well will add to GNPC’s understanding of the Voltaian Basin and help determine the direction of subsequent exploration activity — and, potentially, herald a new era in Ghana’s long search for onshore petroleum resources.
