* Premier swings to H1 profit on higher prices, output
* Soco profit down on higher costs and taxes, output falls
* Premier says drilling could double reserves
* Soco says could quadruple reserves
By Tom Bergin
LONDON, Aug 26 (Reuters) - UK-based explorers Premier Oil (PMO.L) and Soco International (SIA.L) flagged potentially transformational drilling plans for the second half of 2010 as they unveiled mixed results despite higher oil prices.
Soco said its exploration programme already under way in Vietnam and the Democratic Republic of Congo could quadruple its reserves base, while Premier said drilling plans in the North Sea and Indonesia could double its reserves.
“We’re very excited about them,” Premier Chief Executive Simon Lockett told Reuters in a telephone interview.
The company said it was now more confident of reaching its target of producing 75,000 barrels of oil equivalent per day (boepd) in 2012 and Chief Financial Officer Tony Durrant said he expected production of over 100,000 boepd in 2015.
Premier added that a 17 percent rise in first-half oil and gas production and higher prices allowed it to swing to a profit after tax of $62.0 million from a loss of $27.3 million.
Soco’s first-half net profit fell 62 percent to $12.0 million due to a 23 percent drop in production, higher taxes and a rise in costs.
Soco shares were down 1.0 percent at 442 pence at 0755 GMT, while shares of Premier Oil were up 0.3 percent at 1485 pence. Both lagged the STOXX Europe 600 Oil and Gas index .SXEP, which was up 0.9 percent.
Analysts said the reports contained few surprises.
Analysts at Evolution Securities said after a wave of planned mergers announced in recent weeks, Premier remained a potential takeover target but Lockett said he had received no recent approaches. (Additional reporting by Tresa Sherin Morera in Bangalore; Editing by Michael Shields)