More gas for Eni while Anadarko finishes appraisal
With only three wells drilled, Eni has raised its gas-in-place estimate for the Mamba complex in Area 4 to “at least” 1,133 billion cubic metres (cm)
Eni made its third discovery with the Mamba Northeast-1 well in late-March, proving reservoir continuity and pressure-communication with Mamba South-1, 15 km away, and with Mamba North-1, 12 km away.
Mamba Northeast-1, drilled 50 km offshore in water 1,848 metres deep, found 240 metres of gas payzone “in multiple high-quality reservoirs”, the firm said. The well added 283 billion cm to Eni’s previous gas-in-place estimate of 850 billion cm. Of the additional reserves found, 227 billion cm lies entirely within Area 4, while the remainder lies beyond the eastern boundary of the block in an unlicensed area. Eni plans to drill at least another four exploration wells this year.
Meanwhile, Anadarko, operator for the adjoining Area 1, said it had completed the appraisal drilling programme at its Windjammer, Barquentine, Lagosta and Camarão complex – which it has renamed Prosperidade. The firm’s Barquentine-4 well – the most northerly yet drilled at the complex and some 30 km north of the southernmost discovery, Lagosta – found 160 metres of gas payzone. Water-depth at Barquentine-4 was 1,650 metres.
Anadarko said it will now drill two exploratory wells in the northern part of Area 1, into the Atum and Golfinho prospects. The firm views the structures as possible tie-backs to its planned liquefied natural gas (LNG) hub. The company’s second drilling unit is carrying out a flow-test programme at the Prosperidade fields. The company said the first test, at the Barquentine-2 well, showed “exceptional flow characteristics” and indicated that production wells could flow up to 5.7 million cm/d each.
With four discovery wells and five successful appraisals drilled at Prosperidade, Anadarko estimates that it holds recoverable reserves of 480 billion-850 billion cm. The estimate does not include the Tubarão discovery, further south. Anadarko is planning to take a final investment decision on an LNG export scheme towards the end of next year.
Area 4 is held by Eni with 70.0%, joined by Galp Energia, 10.0%, Kogas, 10.0% and the state’s Empresa Nacional de Hidrocarbonetos (ENH), 10.0% (carried through exploration). In Area 1, interests are Anadarko, 36.5%, Mitsui, 20.0%, BPRL Ventures (part of India’s Bharat Petroleum), 10.0%, Videocon (also Indian), 10.0%, Cove Energy, 8.5% and ENH, 15.0% (carried).
UK-Irish Cove, which had invited offers to buy the whole company, received a set-back in March when the Mozambique government said it wanted to impose tax on the sale. Cove sought clarification and in April said it had agreed with the authorities that tax will be levied on the capital gain of its assets in the country at 12.8%. “The formal sale process continues”, the company said. Shell and Thailand’s PTT made bids earlier, and India’s ONGC and Gail are said to be weighing a joint bid.