Run by a Scots veteran of the West African oil industry, Les Blair, Eland has agreed to acquire a 40 per cent stake in the onshore Ubima field for up to $10m (£6m).
The AIM-listed firm has made the move despite suffering interruptions to production from the Opuama field caused by factors including theft of crude through illegal bunkering, a common problem in Nigeria.
Eland said: "A sectional repair of the pipeline has recently been completed and an illegal bunkering point is currently being removed."
Opuama had been pumping 3,500 barrels of oil per day following the delayed start of production in February. Eland had originally hoped to start production from Opuama in the summer of last year. The field on the OML 40 licence had been shut in by Royal Dutch Shell in 2006 amid security concerns.
In May Eland said its performance in 2013 had been significantly impacted by the delay in securing initial production from OML 40, which resulted mainly from contracting and procurement issues.
Recent activity has been completed against a backdrop of concern about the activities of the Boko Haram miltant group in Nigeria.
However, Eland has shown its confidence in the prospects for the industry in the country with the Ubima deal. It will pay the vendor, Nigeria's Allgrace Energy, a $7m signature bonus and a bonus of $3m contingent on production and the granting of required consents.
Mr Blair said: "The acquisition of Ubima is a very attractive and accretive deal for Eland on very positive terms. As the Technical and Financial Partner we will be able to lead the development and move quickly to bring these assets into early production generating strong cashflow."
Following the drilling of four wells on the field between the 1960s and 1981, it has been estimated to contain 34 million barrels of oil, with more finds thought possible.
Eland said it plans to complete a work programme that would cost $125m.
The company disclosed yesterday that it lost $12m before tax in the six months to June, up from $11m in the same period last year.
However, Eland noted it made its first sales of crude from Opuama following the period end.
Mr Blair said: "We are now generating cash from OML 40, which together with the five-year Pioneer tax incentive granted earlier this year and the current and anticipated debt facility means we expect to be fully funded for our current plans. Going forward we anticipate more prolonged periods of stable production."
Eland plans to drill more wells on Opuama and expects the field to be producing around 7000 bopd at the year end in December.
Eland acquired a minority interest in the OML 40 licence in August 2012, in a deal with Royal Dutch Shell, Total and Nigerian Agip worth around £95m.