Magnetic surveys measure the intensity of the Earth's total magnetic field (TMI) produced by the Earth’s core and crust. The Earth’s magnetic field induces a secondary magnetic field in magnetic geological bodies (generally associated with Iron mineral content of rock) which locally produces anomalies. By subtracting the component of the field produced by the Earth’s core (IGRF) from the total field, geophysicists produce residual magnetic intensity field (RMI) maps, which represent the magnetic field produced by local magnetic bodies. In mineral exploration the processed TMI or RMI data are used to map geology and structures or for direct detection of magnetic minerals such as magnetite, pyrrhotite and other ferro-magnetic minerals. The magnetic response of different lithological bodies (related to their iron content or processes responsible for magnetite destruction) can also be used by geologists to interpret the position of contrasting lithologies, alteration zones or the presence of faults, where the magnetic bodies are disrupted by linear features.

Gravity surveys measure the Earth's gravity field, which is sensitive to underlying rock density variations. For example, local mass excess (denser rock bodies) produces an increase in the measured gravity field and local mass deficiency (lesser dense rock bodies) produces a decrease in the measured field. Gravity also being influenced by topographic variations, corrections need to be applied to remove these effects (Free air and Bouguer corrections). These corrections are applied relative to a vertical datum, commonly the sea level. The Bouguer gravity anomaly is the gravity parameter most commonly used for mineral exploration. As for magnetics, gravity may be used to interpret the position of contrasting lithologies such as denser mafic volcanic intrusions or the presence of faults, where denser bodies are disrupted by linear features. Airborne gravity gradiometry surveys measure gravity tensor components corresponding to gravity gradients along three orthogonal directions. This high resolution method is able to detect small targets such as kimberlites pipes which usually show a negative density contrast relative to the host rocks or VMS ore lenses showing a positive density contrast relative to the host rocks.

Electromagnetic (EM) systems operate in frequency or time-domain using a transmitter to emit an EM field which generates a secondary field when encountering conductive material under ground. This secondary field is measured by receivers. Magnetotelluric methods are using natural sources such as global thunderstorm activity as their primary EM field. EM systems use a wide range of frequencies to detect a large range of conductivities. The configuration of the transmitter and receiver coils are used to discriminate between horizontal and vertical conductors. In mineral exploration, the EM measurements can be processed to produce resistivity, time constant (TAU), B field etc. maps for different frequencies or time channels in order to visualise and interpret the EM measurements. Conductivity models can be computed from these measurements or plate models (3D objects) interpreted from EM anomalies. These methods may be used for direct detection of conductive base metal deposits, where a large conductivity contrast exists between host rocks and the mineralisation, for example: massive copper or nickel sulphide bodies. Further, EM methods can also serve to map different lithologies such as resistive intrusions or conductive overburden thickness, faults, alteration processes lowering or increasing rocks resistivity (argillic alteration or silicification).

Electrical resistivity and induced polarisation methods (DC/IP) use current injected in the ground by two transmitter electrodes to measure voltage and decay voltage at two receiver electrodes. IP measurements are made either in the time-domain or frequency-domain. Different electrode configurations can be deployed (pole-dipole, dipole-dipole, etc.). Varying the distance between the transmitting and receiving electrodes results in collecting measurements at different depths. Generally these measurements are visualised as apparent resistivity and chargeability pseudo sections under the electrodes location. In mineral exploration the resistivity measurements can be used to target certain ore bodies showing a good resistivity contrast with the host rocks or map lithologies such as overburden thickness, resistive quartz veins, faults. Chargeability may respond well to disseminated sulphides such as pyritic alteration haloes; clay minerals can also produce a strong chargeability response.

Seismic surveys use seismic waves from either a controlled source such as dynamite or vibroseis trucks or ambient noise source (background seismic signal). When the seismic waves travel downward in the Earth, they encounter changes in the Earth’s geological layering, which cause the signal to be reflected upward to the surface. This signal is then recorded by receivers (geophones or hydrophones) positioned at the surface. Data can be collected in 2D or 3D at surface or underground using borehole methods. Largely used in the oil and gas industry, seismic has been used increasingly in a crystalline rock environment to help interpret ore-related structures, depth to the crystalline basement, faults and for direct detection of certain deposits such as Iron Ore. The seismic waves are processed to produce images and models mapping significant velocity and density contrasts at depth.

Point/line data: Geosoft database (.gdb, .XYZ), ASCII files containing data locations and measurements.

Grid data: gridded products of the data, forming a 2D image of the data, may include filters enhancing the data quality and/or the information contained in the data. They are typically provided in Geosoft GRD format or ERS file format.

Inversion models: inversion process (1D, 2D, 3D) can be performed to model the subsurface distribution of a physical property from field-collected data. These inversion models are usually provided as UBC-ASCII mesh and model files, Geosoft Voxels, ASCII Block Models or OMF (Open Mining Format).

Interpretation products: plate models interpreted from electromagnetic surveys can be available in PTE or DXF format. Interpreted lineaments or picks from geophysical surveys may be available as Shapefile, DXF or ASCII file format.