Production
Average net daily production for 2007 was 41,228 barrels of oil equivalent per day ('boepd'), a decrease of 7.7% over 2006. During 2007, the benefit of Venture's strong underlying reservoir and well performance was constrained by certain exceptional operational events; higher than anticipated downtime on GKA, delay in the start-up of production from the Chiswick field, delay in start-up of production from Chestnut and the continued delay in the anticipated gas 'blow down' within the Birch reservoir. Elsewhere in the portfolio however, Annabel, Saturn and Goosander all outperformed expectations with strong individual field performances in each case.
During the second half of 2007, Venture continued the development of its North Sea asset base, participating in the drilling of eight new wells and bringing one new field on stream.
Average net daily production for 2006 was 44,706 barrels of oil equivalent per day (boepd), an increase of 50% over 2005. This resulted from new field developments coming on stream combined with good reservoir and well performance supported by improved levels of production facilities uptime. Venture's southern North Sea (SNS) gas fields contributed 61% of total 2006 production, slightly higher than expectations, with the balance from Venture's central North Sea (CNS) oil fields.
During the fourth quarter of 2006, despite difficult weather related offshore operating conditions toward the end of the year, Venture's average production rate reached approximately 54,000 boepd, a new record for the Company.
In 2005, annual net production averaged 29,864 barrels of oil equivalent per day ('boepd'), an increase of 74% over average 2004 production levels.
Reserves
At 31st December 2007, net proven and probable reserves are estimated to total 202.4 million barrels of oil equivalent ('MMboe'), including the Company's proportionate share of reserves in Trinidad. This represents an 8.5% fall from end 2006 and is principally the result of production in the year and the re-categorisation of probable reserves from the Pilot field to contingent resources as previously indicated it also reflects the absence of any completed acquisitions of proven and probable reserves during a period in which business development activity has largely delivered important additions to our exploration and appraisal portfolio. Excluding the impact of Pilot, Venture's organic reserve replacement ratio was 90% for 2007.
In terms of hydrocarbon split, Venture's southern North Sea ('SNS') gas fields contributed 60% of total 2007 production with the balance coming from Venture's portfolio of central North Sea ('CNS') oil fields.
At 31st December 2006, net proven and probable reserves are estimated to total 221.5 million barrels of oil equivalent (MMboe), a 37% increase over 2005. This growth reflects a reserve replacement ratio, including acquisitions, of approximately 455%, which has been achieved net of the sale to partners of a proportion of Venture's interest in the Ensign development during the year.
At 31st December 2005, proven and probable reserves were estimated to total 161 million barrels of oil equivalent ('MMboe'), a 29% increase over the Company's reserves at the end of 2004.