Rovuma Basin - Basic Factfile

·         The Rovuma basin is circa 400km long and 160km wide and spans the southern border of Tanzania and Mozambique at the coast. 

·         Offshore, water depth ranges between 550m and 2000m

·         Mocimboa-1 was drilled onshore in Mozambique in 1986 by Esso. Small amounts of condensate were noticed in the Albian Sands

·         Rovuma hydrocarbon plays are mainly in the pre-rift fault blocks, stratigraphic traps and structural traps

·         Mnazi Bay-1 was drilled in 1982 in the Tanzania onshore location with flow rates of 14mmcfd from Oligocene sands

·         3200km2 2D seismic was made offshore in the late 1990’s

·         In the West onshore part of the basin sediments total 11km in thickness. The thickness tapers towards the East

·         First exploration in 1980 by CGG Group who shot 15000km2 of aeromagnetic data

·         In 2007 Artumas confirmed the presence of a high pristine/phytane ratio and an abundance of aromatic hydrocarbons which are significant indications of a Tertiary based source rock with oil potential in Mnazi Bay

·         Wentworth has attributed 1.3TCF GIP at a P50 level to its Rovuma Onshore acreage which covers 13500km2 and 2.8TCF unrisked in its Mnazi Bay license at P50 level

·         Aminex PLC assigned 2.44TCF for structural and 3.23TCF for stratigraphic leads for its portion of the onshore Rovuma basin (6079km2) in the Northern/Tanzanian side of the basin in July 2012

·         Aminex PLC flowed 139 barrels of condensate plus 20.1mmcfd from a 3.5m section of its Ntorya-1 well with initial pressure readings around 5400psi

·         Some of the current companies working in the Rovuma Basin include ; Statoil, BG Group, Ophir Energy, Anadarko, Aminex, Wentworth, Solo Oil, Tullow Oil, Eni, Maurel et Prom

·         Anadarko’s Mecupa-1 well encountered a good quality reservoir with hydrocarbon shows in late 2009 in Miocene sands. It was plugged and abandoned

·         Wentworth’s Ziwani-1 well flowed up to 7.2mmcfd at an unstable rate with wellhead pressures at 973psi from a 3m section

·         Ophir energy has made 3 offshore gas finds in the Rovuma basin; Mzia-1 (3.5TCF), Jodari-1 (3.4TCF) & Chaza-1 (0.47TCF)

·         Eni encountered in excess of 15TCF of gas at its Mamba South-1 prospect in the offshore section of the Basin having already found 15TCf at its Mamba North-1 prospect at a depth of 5330m. Eni also made another 7-10TCF discovery at its Coral-1 well in the same sort region as well as estimating reserves at its Mamba North East-2 well at 10TCF

·         Aminex drilled Likonde-1 in 2010 onshore in the Tanzania part of the basin revealing 820ft of sandstone reservoirs. Core cuttings revealed residual oil readings
·         Anadarko has uncovered huge gas deposits at its Prosperidade complex over the last few years through successes at its Barquentine, Lagosta, Camarao, barquentine-3, lagosta-2 and lagosta-3 wells amounting to resource estimates being in the range of 17-30TCF+ in high quality Oligocene sands. No upper limit has been given. Flows have been huge at 100mmcfd when constrained and 200mmcfd when unconstrained

·         Anadarko has also announced large resources at its offshore Atum and Golfinho complex with resources between 10TCF and 30+TCF in high quality Oligocene fan systems at shallower water depths than Prosperidade. Further south in the basin Anadarko revealed a discovery between 0.2-1.7TCF recoverable at its Tubarao well

·         In August 2010 Cove Energy discovered liquid hydrocarbon shows at its Ironclad well which was confirmed by geochemical analysis
AT P50 (for undiscovered) and P90 (for discovered), USING TCF FROM ABOVE TOTALS TO 128.84TCF OF WHICH MOST IS DISCOVERED. The upside potential here is huge in terms of resources with almost every well drilled here hitting hydrocarbons

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