The super giant Mamba field is located in the Area 4 deep water block, offshore northern Mozambique. Hosting over 80 TCF of natural gas, the Tertiary reservoir complex will supply a new LNG plant. The Coral reservoir represents the Lower Eocene reservoir unit of the Mamba Complex, which is formed by turbidite channel and lobe deposits of several deepwater basin floor fan accumulations. Generally, the coarse and massive reservoir sandstones are extraordinarily thick, clean and homogeneous compared to other deep water plays, e.g. GOM, West Africa. High quality 3D seismic and data from three wells, including 144m core, indicate that the excellent reservoir quality of the Mamba complex can be related to the presence of strong, deep water bottom currents that influenced the deposition of gravity-flows. An integrated sedimentological approach on multiple scales, which comprises detailed sedimentological core descriptions, seismic stratigraphy and seismic attribute analysis, provides new insights into the depositional processes and the reservoir architecture of a fascinating deepwater play. The depositional model suggests Lower Eocene bottom crossing the sand rich gravity flows perpendicularly. This results in significant flow-stripping and deviation of the turbulent, fine-grained suspension cloud. The process accumulates the greatest amount of fines on the leeward part of the channel complex and creates unilateral drift-mounds instead of bi-lateral levee complexes. This leads to relatively mud-free facies types and a characteristic low angle offset stacking of the amalgamated channel complexes. However, dependent on associated flow-velocities and grain sizes, also the depositional lobes show exceptionally good reservoir properties, characteristic geometries and stacking patterns. The integrated and process-oriented approach allowed detailed mapping and modeling of the reservoir bodies, which permits prediction of reservoir quality and optimization of the field development.

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