(1)  Where the Minister is satisfied that the rate of recovery of petroleum from a well has become so reduced that, having regard to the rate or rates of royalty applicable under section 142 , further recovery of petroleum from that well would be uneconomic, the Minister may, by instrument in writing, determine that the royalty in respect of all or any of the petroleum recovered from that well on or after a date specified in the determination shall be at such rate, being a rate lower than the rate that would be applicable under section 142 , as the Minister specifies.

(2)  The prescribed rate in respect of petroleum to which a determination under subsection (1) is applicable is the rate specified in the determination.