LONDON, Jan 10 (Reuters) - Current high levels of investmentin Britain's North Sea are unlikely to continue after 2015,according to a forecast from energy consultancy Wood Mackenziethat could feed concerns about the longer-term future of thecountry's oil industry.
Britain's oil and gas output has fallen by about two thirdssince 2000, posting particularly steep falls of 14.5 percentlast year and 18 percent in 2011, but big new investments havefuelled hopes that some of the declines can be reversed.
In 2013, capital investment in the UK part of the North Seahit its highest level in real terms since the mid-1970s, WoodMackenzie said in an annual report published on Friday, butcautioned that higher spend was also a result of rising costsand that it was not likely to continue.
"Due to poor exploration performance in recent years,capital investment is unlikely to be sustained at the currenthigh levels beyond 2015," Wood Mackenzie's head of UK upstreamresearch Lindsay Wexelstein said.
Britain's government is battling to revive the North Sea,whose plunging output has acted as a drag on economic growth,and has commissioned a review to help it do so, but the risingcost of projects and a dearth of new discoveries in the maturearea, in its fifth decade of pumping oil, means reversing thedecline is challenging.
In November, for example, U.S. oil company Chevron threw doubt on its North Sea Rosebank project, a big developmentthought to cost around $8 billion, saying it was not currentlyeconomically attractive.
On the exploration front, the last two years have been lighton success, Wexelstein said, blaming lower drilling rates assome smaller companies struggled to raise funds for exploration.
Combined investment in the North Sea over last year and thisyear will reach 21.3 billion pounds ($35.1 billion), WoodMackenzie forecast, in line with guidance provided by industrybody Oil & Gas UK which said in August it expected 2013 capitalinvestment to total 13.5 billion.