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What: Shares of South American oil explorer Gran Tierra Energy (AMEX: GTE) are up 11% today after the company started exploratory drilling in Brazil.

So what: In Brazil the company has begun exploratory drilling operations on one offshore prospect and one onshore prospect. Drilling in Colombia has indicated an additional oil column in Moqueta that could add to the company’s reserves.

Now what: Details of the Moqueta discovery were sparse today but likely were the driving force behind the shares moving higher. The company is expecting to begin a “robust 2012 drilling program” in Brazil, Colombia, Peru, and Argentina in wholly owned sites and joint ventures. The market is expecting a good year in 2012, and with the company’s forward P/E standing under 10 the upside potential is looking attractive.

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