That all oil and gas leases issued by the commissioner of public lands of the state of New Mexico prior to the effective date of this act [section], in substantial conformity with the statutes of the state, the terms of which have not expired and where all rentals have been paid thereunder and accepted by the commissioner of public lands, and such leases have not been canceled by the commissioner of public lands for nonperformance by the lessee or any assignee, are hereby declared to be valid and existing contracts with the state of New Mexico according to their terms and provisions, and the obligations of the state and of the commissioner to observe and conform to the terms and provisions thereof are hereby recognized.
NMS § 19-10-49