African oil production along the Atlantic littoral has attracted huge exploration investment, and the region will contribute more than 30 percent of the world's increase in liquid hydrocarbon production by 2010.

CNN: The price of our oil addiction

The primary difference between bitumen and ordinary crude is the size of the hydrocarbon molecules: in liquid oil, these molecules contain between five and twenty carbon atoms, while in bitumen they contain more than twenty. (At room temperature, pure bitumen is so viscous that it will not flow.) The main job of the upgrader is to break down the oversized hydrocarbons into smaller units.

NEWYORKER: Unconventional Crude