Light sweet crude is depleting quickly, and now the industry is going after heavy crude and tar sands and thermally enhanced oil.

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Crude from the tar sands and other unconventional sources could keep oil flowing well into the middle of the century, and perhaps beyond.

NEWYORKER: Unconventional Crude

All the applications opposed by Fort McMurray officials were ultimately approved, and just a few months ago an American company, Hyperion Resources, announced plans to build the first new oil refinery in this country in thirty years, to handle increasing volumes of tar-sands crude.

NEWYORKER: Unconventional Crude