about methane

It should come from crude oil....

For more information,
Fractional distillation of crude oil will give out many hydrocarbons in each fraction;
The first fraction that the number of carbon atoms is 1 (methane)will be first given out;

Let me remind you that the main component of natural gas is methane,so methane should then come from crude oil.

Hoping it will be useful for you.

2007-12-29 19:36:08 補充：
Fractional distillation of crude oil will give out different hydrocarbons in each fraction

natural gas: mainly methane(CH4) +a few C2H6, C3H8, C4H10
在油礦以氣體存在

oil提練出來的mainly是buthane, C4H10, 又叫石油氣LPG