Exploration means the process of searching for minerals on a lease including:
(1) Geophysical surveys where magnetic, gravity, seismic, or other systems are used to detect or imply the presence of minerals;
(2) Any drilling including the drilling of a borehole in which the discovery of a mineral other than oil, gas, or sulphur is made and the drilling of any additional boreholes needed to delineate any mineral deposits; and
(3) The taking of sample portions of a mineral deposit to enable the lessee to determine whether to proceed with development and production.
30 CFR § 582.3
When used in this part, the following terms shall have the meaning given below: