Petroleum Hydrocarbons and Natural Gas Liquids

Currently, the largest source of energy that is used in the anthrosphere consists of hydrocarbon liquids, the majority of which are composed of hydrocarbons pumped from the ground as liquid petroleum. An increasing share of these liquids now comes from heavy oil and bitumen, which, in 

Proven world reserves of crude oil and natural gas liquids are about 1.2 trillion barrels. An annual production rate of 85 million barrels per day provides an estimated 40-year supply of these hydrocarbons. However, these hydrocarbons will be used much longer than that because more will be found, substitutes will be developed, and use will decrease as supply limits are approached. 

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