The Rusk, Bertagne & Associates (RBA) study includes coastal and offshore sectors of Mozambique, southern Tanzania, northern and western Madagascar and the Comoros Islands, a total area of approximately 1.3 million square kilometers, which represents more than one-third of offshore East Africa; and, incidentally, an area greater than the North Sea.
This vast frontier incorporates nine basins, with Permo-Triassic to Neogene sedimenitary sections ranging in thickness from 6000m.to 12,000m. In addition, on the onshore and coastal periphery of these basins, oil and gas has been discovered: 1. In southern Tanzania, the Songo Songo gas field, is currently producing; and Kiliwani/Kiliwani North and Mnazi Bay-1 gas discoveries have reserves exceeding 2 TCF; 2. In Mozambique, the onshore Pande-Temane gas field complex has 5 to 6 TCF; and, in January 2014, Sasol made a small oil discovery near the Temane gas field; 3. Onshore Madagascar, the Bemolanga-Tsimiroro area has a minimum of 25 Billion barrels of tar and heavy oil-in-place.
In spite of the regional expanse, favorable geologic setting and oil and gas occurrences, prior to 2010 only 26 offshore exploration wells were drilled in the RBA study area, none of which, were in deep water.
However, within the last 9 years, more than 21 oil companies have acquired rights to deep water E. & P. licenses, for most part, via joint ventures, in Madagascar, Mozambique, Tanzania and the French Economic Zone of Juan de Nova. The companies are as follows: Anadarko, British Gas, CNPC, Dominion, Enermad, ENI, ExxonMobil, GalpEnergia, KOGAS, MAREX, Ophir, ONGC, Petrobras, Petronas, Sapetro, SKCorp, Statoil, Sterling, Total and Tullow. Roc Oil and Vanco no longer have participation in this region.
The licenses currently held by the above companies cover areas which total only 30 percent of the study area. From 2005 to 2007, six companies, now joint venture company groups, acquired deep water licenses in the Rovuma Basin sectors of Mozambique and Tanzania, as result of licensing rounds: Ophir and Statoil acquired three blocks and one block, respectively, in Tanzania. In the Mozambique sector of the Rovuma basin, both Anadarko and ENI acquired one deep water block and both Petronas and Statoil acquired two deep water blocks.
In the 2007 Madagascar western offshore licensing round, Roc Oil/Marex (now Sapetro/Marex) were awarded nine deep water blocks and Enermad was awarded 6 offshore blocks. These awards represent only 16 % of the blocks offered. In December 2008 Roc Oil/Marex (now Sapetro/Marex) were awarded the very large Juan de Nova permit by France. Meanwhile, the current license status of Madagascarís northern offshore Majunga Basin, after several years of negotiations, is as follows: ExxonMobil, two blocks, ExxonMobil/Sterling, one block and Sterling, one block; representing 80 to 85% of Madagascarís northern offshore. At present, ExxonMobil is preparing to drill the first of three offshore commitment wells; after a 6 year delay due to Force Majeure.
The first deep water exploration well in the RBA study area, was drilled in the Rovuma Basin in 2010. Since then, 34 of 41 deep water wildcats drilled in the study area were major Tertiary sandstone gas discoveries. A few of these discoveries had Upper Cretaceous sandstone gas pay. The discoveries have a total estimated gas-in place of 200 to 230 TCF, as follows:
1. Anadarko Group: eleven discoveries with 80 to 90 TCF.
Potentially more important than the Rovuma Basin Tertiary gas resources are the Mesozoic oil plays. Permo-Triassic to Upper Cretaceous objectives have not been pursued in the study area, with the exception of four dry holes drilled in 2013, only one of which reached Upper Jurassic. In addition, seven of the basins in the study area, have Mesozoic sections with thicknesses ranging from 4000m. to 8000m.
This un-licensed and un-drilled offshore frontier, excluding the Rovuma Basin and existing licenses, covers more than 900,000 square kilometers, which is 70 percent of our study area.
In 2014, this great open area will be the site of major bid rounds by Tanzania, Mozambique and Madagascar; and all of the numerous blocks offered will be located in our study area. Tanzania, which opened a bid round for nine blocks in October, 2013, will close the round in mid-year. Mozambique and Madagascar will launch their extensive bid rounds in November and December, respectively.
The RBA report:
The basis of the study is our exclusive use of approximately 31,000 km. of reconnaissance seismic data acquired between 1972 and 1989 and owned by French scientific institutions and made available to RBA under certain contractual conditions. Prior to the onset of the study, this seismic data set were not available to the oil industry. Approximately 25,000 km. of these seismic data are now available for sale, limited to purchasers of the RBA report.
The above French legacy seismic data has been integrated with about 3,000 km. of shallow water seismic and a comprehensive data set from pre-2010 onshore and offshore wells. They also have been supplemented by a 2000 km state-ofĖthe-art seismic 2D pilot study acquired in 2001 to verify the major regional structural and stratigraphic elements including integration with 119 core holes and bottom drag samples obtained by various French scientific missions from 1970 to 1989 which provide strategic information for seismic correlations on the Davie Fracture Zone.
In addition to interpreting, synthesizing and mapping the stratigraphy and structural configuration of each basin, we have identified an abundance of major structural leads, some salt related, with horizontal and vertical dimensions analogous to world-class giant fields.
Geochemical analyses of data from oil seeps, surface outcrops and wells, along the periphery of the study area, have provided documentation for the following: 1. Rich, effective oil-prone source beds of Permo-Triassic, Lower and Middle Jurassic and Upper Cretaceous ages are present in six of the nine subject basins; and, 2. Gas and mixed oil & gas source beds of all epochs from Permo-Triassic to Upper Cretaceous are present in seven of the nine subject basins.
Offshore Basin Evaluation Summaries, Appendix I, is of particular importance in regard to area or basin comparison and focus. Each of the nine basin evaluation summaries includes a concise compilation of petroleum systems and related elements, with risk analyses. Appendix II comprises complete formation and age tops on more than 110 wells.
Finally, the combination of an extensive data set and the 50 years of hands-on experience in the region, by authors R. G. Bertagne and D. C. Rusk, and associate Giovanni Flores, attests to the scope of the technical effort and expertise applied to this project.
The text, all enclosures and appendices are of the study are in digital form and available for immediate delivery. The all-inclusive cost for the RBA report is US$85,000. All sales are handled by D. C. Rusk and R. G. Bertagne.