Okla. Stat. tit. 60, § 60-6: Land defined

A. Land is the solid material of the earth, whatever may be the

ingredients of which it is composed, whether soil, rock or other

substance, and includes any pore space.

B. 1. As used in this section, “pore space” means any

interstitial space not occupied by soil or rock, within the solid

material of the earth, and any cavity, hole, hollow or void space

within the solid material of the earth.

2. As used in this section, pore space is real property and,

until title to the pore space or rights, interests or estates in the

pore space are separately transferred, pore space is property of the

person or persons holding title to the land surface above it.

3. Notwithstanding the ownership of the pore space, nothing in

this section shall alter or be construed to alter the ownership of,

or rights associated with the oil or gas, as those terms are defined

in Section 86.1 of Title 52 of the Oklahoma Statutes, that may be

within the pore space.