Abstract: The geologic characteristics of giant oil-gas fields, more than 1 000 deep oil-gas fields and continental shelf oil-gas fields as well as natural gas hydrate pools in MidEast, South-North America are analyzed. These oil-gas fields may not be rationally explained by organic origin theory whether in oil-gas reserves and occurrences or in geologic characteristics of hydrocarbon distribution. Numerous measured data prove that a mass of hydrocarbons have been found in volcanic products, commercial gas flow found in crystal basement of Precambian and a series of hydrocarbon compounds found in cosmic stars and extraterrestrial spaces. All these indicate the possibility of inorganic origin for hydrocarbons. The inorganic origin theory for hydrocarbons provides a wide prospect for deep oil-gas development.

Key words: hydrocarbon origin, organic origin theory, inorganic origin theory, Fischer Tropsch (FT) reaction, deep hydrocarbon