If you have several producing zones at varying depths, can you have multiple leases one for each zone?
Yes, I believe so. One could stipulate that a lease extends from the surface to the top of the "x" formation, for instance. And then have a second lease cover from the top of the "x" formation to the top of another formation. And so on. But finding companies to go along with this might be a challenge. It is also possible for a company to have leased one's land and then turn around and lease out deeper rights to another company, assuming the original lease does not prohibit such activity.