Netherlands-based Mazarine Energy and Tunisia’s national oil company, Enterprise Tunisienne d’Activities Petrolieres (Etap), have announced a discovery in Tunisia’s Zaafrane permit.

The discovery was made by a well named Cat-1, which was drilled to test the potential of two geological formations named Ordovician el-Hamra and El-Atchane.

The two formations each hold about 19 million barrels of oil, according to testing carried out by Mazarine Energy.

During a production test, when the flow was constrained by surface facilities, the well saw an oil flow-rate of 4,300 barrels a day (b/d).

The flow rate for gas was 395,000 cubic metres a day (cm/d).

The Zaafrane permit spans an area of 5,168 square kilometres within a historically prolific oil-and gas-producing region. Mazarine Energy is the operator of the Zaafrane permit, with Etap and Medex as partners. The well was drilled by Compagnie Tunisienne de Forage (CTF) to a total depth of 3,950 metres.

“The Cat-1 well… upgrades the resource potential of a string of prospects in this large permit, notably DGH-1, our next well in the sequence,” said Mazarine Energy executive chairman Edward van Kersbergen in a statement released on 1 May.