FinanceDone deals: Savannah pays $626m for ExxonMobil and Petronas assets in Chad and CameroonLondon-listed indie targets output boost from neglected oilfields in Chad and increased use of Chad-Cameroon oil pipelinePotential: ExxonMobil has been using polymer waterflooding to boost oil recovery from oilfields in Chad's Doba basinPhoto: EXXONMOBILIain EsauLondon