Underground and undersea porous sedimentary rocks are a source of this specific type of hydrocarbon gas, along with crude oil as petroleum. Its mixture is primarily 85 percent methane, 10 percent ethane, and 3 percent propane. Butane, carbon dioxide, hydrogen sulfide, nitrogen, and oxygen fill the percentage. It is an essential feedstock in the chemical industry for fertilizers, methanol, and other organic and synthetic materials manufacture. It is also a fuel in other industries. Also refer to petroleum gases and petroleum.
