Pitched at 19.21p per share the takeover offer values the junior South American oiler at £242mln, which would be a premium of 59% to the market value when a sales process and offer period officially commenced back in July.
In London this morning, Amerisur shares were changing hands at 18.8p.
Geopark has irrevocable undertakings in support of the proposed transaction accounting for some 18.9% of Amerisur’s shares, whilst at the same time Amerisur’s director’s beneficial holdings amount to 4.9% - meaning that 23.8% of the equity is behind the transaction.
A general meeting will now be due in December for other shareholders to vote on the deal.
Amerisur chairman Giles Clarke highlighted that the formal sales process was a “very thorough exercise” with multiple parties given access to data and presentations held in Bogota.
“The market for Amerisur has been fully tested and the board is unanimously recommending this condition light offer to shareholders," he said.
Chief executive John Wardle, meanwhile, added: “Today underlines the success Amerisur has achieved in building an attractive E&P business in Colombia. The strategic portfolio of assets is an excellent fit for GeoPark, which, as a leading independent Latin American E&P, is well positioned to maximise the potential.”
Geopark chief executive James Park said: "A consistent pillar of GeoPark's long term value proposition has been and will continue to be inorganic growth, including M&A and block acquisitions.
“Amerisur's asset base in Putumayo will provide GeoPark with access to an underexplored high potential basin, as part of our larger Marañon-Oriente-Putumayo strategy in the region and with an operating export pipeline.
“Additionally, with the incorporation of the CPO-5 block, operated by our strategic partner ONGC, and adjacent to our prized Llanos 34 block and nearby recently awarded exploratory blocks, GeoPark would now have a contiguous land position of more than one million gross acres in one of the most productive areas of the Llanos basin in Colombia, containing multiple development and exploratory opportunities.”