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Wednesday, March 21 2018

5:30 PM - 8:30 PM
Wednesday, Mar 21, 2018 5:30 p.m.
Intl. Dinner

The Mozambique Channel can be divided geologically into three provinces:

The western sedimentary province with a thick Mesozoic/Tertiary sequence representing the late Zambezi flood plain and consisting of eastern dipping clastics alternating with turbidite channels oriented essentially in a north south direction along the west flank of the Davie Fracture Zone.

The petroleum systems are analog, in part, to those of the Rovuma basin with proximal or in situ generation of hydrocarbons in an anoxic environment migrating into overlying clastics (Mandawa-7 well). A more recent system consisting of Tertiary gas generation migrating into turbidites with very large porosity and permeability has been discovered nearshore Mozambique in areas 1 and 4 (Golfinho/Atun and Coral fields 146TCF).   

The Davie Fracture Zone (DFZ), a major tectonic element extending for 2300 miles (3700 km) along East Africa offshore from Somalia to southern Madagascar. The portion in the Mozambique Channel consists of restructured Jurassic sediments capped by mid to late Cretaceous clastics which were exposed to massive erosion by the waters of the Zambezi river in mid Cretaceous time and further rejuvenated in Tertiary through the infusion of crystalline material.

The major petroleum system on the DFZ is the Jurassic which is hydrocarbons prone onshore western Madagascar as a source (most likely oil) with migration into the Cretaceous sands with provenance from western Madagascar and the Turonian volcanics as a seal. The trap is the classical anticlinal type formed by the uplift of the DFZ. Accretionary wedges on the west flank of the DFZ may also be considered as gas prone prospects

The Malagasy micro plate to the east of the DFZ consisting of a relatively quiet province from a structural and stratigraphic standpoint with continuous sedimentation from Permian through Tertiary and the formation of drag folds expanding into flower structures caused by the reactivation of older Karoo sinistral transforms typical of the African craton as a consequence of the rejuvenation of the DFZ in mid Cretaceous and Tertiary.  

Six distinct petroleum systems can be found on the Macua uplift ranging from upper and middle Cretaceous deep basin fans sourced by the Jurassic (undefined) through upper, middle and lower Jurassic four way closures and finally the Permo Triassic system of the Bemolanga tar sands on Triassic flower structures.

In 2012 the USGS basing its estimates on existing exploration and production data estimated that 22.4 billion barrels of oil, 349 TCF gas and 10.7 million barrels of natural gas liquids remained to be discovered in the Mozambique Channel between Mozambique and Madagascar. Based on recently discovered reserves and newly obtained geological/geophysical data and studies it is reasonably expected that these figures can probably be doubled.