What is petroleum?

There are some places on earth where oil is not trapped underground, but actually seeps out at the earth's surface—Think Jed Clampett and a "bubbling crude!" This is one of the largest natural petroleum seeps, located in the upper Ojai Valley, California. About; Links. pe·tro·le·um petroleum. read more

Petroleum (/ p ə ˈ t r oʊ l i ə m /) is a naturally occurring, yellow-to-black liquid found in geological formations beneath the Earth's surface. It is commonly refined into various types of fuels. read more

Petroleum definition, an oily, thick, flammable, usually dark-colored liquid that is a form of bitumen or a mixture of various hydrocarbons, occurring naturally in various parts of the world and commonly obtained by drilling: used in a natural or refined state as fuel, or separated by distillation into gasoline, naphtha, benzene, kerosene, paraffin, etc. read more

The word petroleum comes from the Latin petra, meaning “rock,” and oleum, meaning “oil.” The oil industry classifies "crude" by the location of its origin and by its relative weight or viscosity ("light", "intermediate" or "heavy"). read more