Brazilian state-run oil firm Petrobras has begun a long-term test in the Forno area in the Albacora Field in the presalt region of the Campos Basin, the company said in a securities filing May 17.

The testing, started May 16 and being carried out in the well about 120 kilometers off the coast of Rio de Janeiro, aims to assess the “reservoir’s production and characteristics of its oil,” Petrobras said in a statement.