In 1998 Marathon discovered the East Orovinyare field. The discovery well encountered a 100 metre oil column in the Upper Cretaceous sandstones of the Batanga Formation. Marathon relinquished the licence in 2000 following an unsuccessful farm out attempt. Bowleven gained ownership of the East Orovinyare field in 2007 when it acquired FirstAfrica Oil. In March 2012 Bowleven sold East Orovinyare for US$35 million to Perenco.