Recent discoveries offshore Tanzania and Mozambique highlight East Africa as an emerging world-class pet-roleum province. Oil and gas estimates for this province total 12.5 BBO and 250 TCFG (Brownfield et al., 2012) as yet undiscovered. Play-opening reservoir systems have been verified in Paleocene, Eocene, and at least two Oligocene deep-water submarine fan and intraslope channel complexes (Law, 2011). In deep-water Tanzania, there have been seven gas discoveries (of eight attempts) since 2010, with recent announcements putting total gas reserves in Tanzania at 24–26 TCFG. In neighboring Mozambique, 19 wells were completed by Anadarko and ENI in the Ruvuma Basin from 2009 to June 2012, only two of which were not announced as commercial discoveries. With the additional drilling, the increase of reported reserves now approaches or exceeds 100 TCFG. Evidence continues to mount that suggests the Late Cretaceous section contains deposits from similar depositional settings (Tanzania Petroleum Development Corporation, 2003). There are also indications that the petroleum system may contain oil as well as the established gas.