In 2005 Maersk Oil bought a 50% share in Block 16 in Angola and in 2009 it drilled its first prospect in the block, which turned out to be a discovery. Two years later Chissonga was declared commercial.

The Chissonga field is located in the western part of Block 16, some 130 km offshore from the Soyo beach crossing, in a water depth ranging from 1,200 meters to 1,500 meters.

The first appraisal well was completed in April 2010 and further appraisal wells were drilled in late 2011, 2012 and 2013 to define a more accurate resource range in the stacked turbidite sand reservoirs.

The Chissonga reservoir comprises four stratigraphic layers with hydrocarbon accumulations. Following appraisal, the optimal development concept is currently being matured.