Sydney-based minority Maari partner Horizon Oil NL (formerly Bligh Oil and Minerals) says the report - by Perth-based Resource Investment Strategy Consultants - confirms the quality and significance of both projects to Horizon.
"We are very pleased that we have an independent substantiation for the positive analysis and views previously communicated to shareholders about the likely value of these two key projects," says Horizon chief executive Brent Emmett.
"Strategically these assets fit well with the board and management's stated game plan, which is to build a balanced portfolio including lower risk projects that can be managed to a value peak over a three to five year period."
The RISC report analysed the "low, medium and high" reserves cases for each project at an 11% discount rate and oil prices of $US22 per barrel.
The medium case indicated recoverable reserves net to Horizon Oil of 11.3 million barrels of oil (mmbo), while the high case yielded net reserves of 22.0 mmbo. The low case also had a positive NPV, and if oil prices remained above $US17.10 per barrel Horizon would still achieve an 11% rate of return.
Initial production from both projects, net to Horizon, was forecast to be 8000 bopd from early 2006, with after-tax cashflows starting at $A53 million per annum, increasing to $A102 million using RISC's high case scenario of a $US27 oil price.
RISC says it has recalculated the likely recoverable reserves for Maari and gives a P50 figure of 49 million barrels of oil from the Moki and Mangahewa reservoirs, plus the M2A sands.
RISC further says it estimates P50 recoverable reserves from the Manaia prospect, to the southwest of Maari but still within exploration licence PEP 38413, of six million barrels of oil.
The most promising development options are a minimum facilities platform, with surface wellheads connected to an FPSO or subsea wells tied back to an FPSO. Long horizontal or multilateral wells are preferred.
RISC estimates the total cost for PEP 38413 to be between $US241-412 million spread over 11 years, depending on the chosen development scenario.
The schedule supplied by operator OMV indicates concept selection narrowed to two options by this quarter, with final investment decision in the second quarter of 2004 and first oil in the first quarter 2006.
Emmett said priorities for Horizon now included securing the appropriate financing for the company's share of development capital expenditure, and contributing expertise and support to Maari operator OMV Petroleum and Block 22-12 operator Roc Oil (China) Company, to ensure the optimal and timely development of the fields.
Last month Horizon completed its exit from onshore Taranaki, with Indo-Pacific Energy acquiring its equity in four onshore Taranaki exploration assets, so Horizon could concentrate on offshore Taranaki, particularly on its 10% stake in the Maari project.
