Method | Measured parameter | Used physical property | Suitable deposits type |
Seismic | Travel time of reflected & refracted waves | Density and Elastic mode Velocity and Acoustic | Coal, Oil, Gas, Groundwater, Layered sedimentary basin, Ni- Cu- PGE in volcanic basal flows |
Gravity | Gravity (Variation in earth’s gravitational field) | Density contrast between the surrounding and host rock | Massive sulfides, Chromite, Ni-Cu- PGE, Salt dome, Barite, Kimberlite pipes, Concealed basins |
Magnetic | Variation in Earth’s magnetic field | Magnetic susceptibility | Magnetite, Ilmenite, Pyrolite-rich sulfides, Ni-Cu-PGE |
Electrical (Resistivity) | Earth’s resistance | Electrical conductivity | Groundwater, Sulfides, Ni- Cu- PGE |
Electrical (Induced potential) | Polarization voltage/ frequency development of ground resistance | Electrical capacitance | Large sulfide dissemination, Ni- Cu- PGE, Graphite |
Electrical (Self potential) | Electrical potential | Electrical conductivity | Sulfide veins, Graphite, Groundwater, Ni- Cu- PGE |
Electromagnetic | Response to electromagnetic radiation | Electrical conductivity and conductance | Sulfide, Cr- Ni- Cu- PGE ore, Graphite |
Radiometric | Gamma radiation | Gamma ray | Thorium, Uranium, Radium |
Borehole geophysics | Downhole probe | All types | Continuity of sulfide, Ni- Cu- Cr- PGE in strike and depth |