Crude oil and natural gas is lighter, it will move to prevent access to stored in a specific area of the body prunes stones of each structure and will be planted with a stone floor texture that is closed.
Crude oil and natural gas are lighter to move. To retain the texture of porous rock layers. Only the higher regions of each structure. And is trapped by the rock texture. The cover is
Crude oil and natural gas, there is light to move to the reservoir in porous rock texture The height of each structure. And be bound by the rock texture, the seal.