Petrolinvest's OTG Oilfield Estimates raised

    Estimates of oil resources at exploration firm Petrolinvest's OTG oil field in Kazakhstan were raised by 300 million barrels to 1.27 billion, Petrolinvest said on Thursday, quoting a report by McDaniel and Associates.     Petrolinvest controls nearly half of the OTG field, and will raise its stake to over 98 percent after...