Sweet light crude oil yields the most gallons of gasoline per barrel of oil and since it has low viscosity and low density, it is comparatively inexpensive to pump, transport, and refine.

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The ongoing conflict there has resulted in the removal from global markets of roughly 1.6 million barrels per day of light, sweet high-quality crude oil a total of more than 150 million barrels displaced since the conflict began.

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World crude oil production has in some cases already peaked (sweet, light) while others (heavy, sour) it has yet to be will soon.

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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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