(El Universal) - For more than a quarter of a century, the cluster of platforms off southern Mexico´s Gulf coast has been the main source of the country´s vast oil exports, providing about 35 percent of the government´s annual revenue.

Cantarell, as the oil field is known, is the world´s third biggest and responsible for about 60 percent of the 3.4 million barrels Mexico produces each day. The oil has been cheap to extract. Whereas many of the world´s important reserves are thousands of meters below ground in geologically challenging and climatically harsh environments, the deepest well at Cantarell is barely 60 meters.

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