Exploration Geophysics

Time Domain EM Surveys

The time-domain electromagnetic (TDEM) technique utilizes differences in the electrical properties of geologic materials to map subsurface conditions. An electric current is induced into the ground by a loop of wire laid out on the ground surface. These induced currents propagate downward into the subsurface and are increasingly influenced by the electrical properties of deeper layers. A series of measurements of the secondary magnetic field are used to model electrical resistivity as a function of depth. Changes in subsurface resistivity values can result from changes in lithology, water content, pore-water chemistry, and the presence of buried debris.

Mineral Exploration

Mapping Groundwater Aquifers, boundaries, saltwater intrusions and fault zones

Geological Stratigraphy Mapping

Detecting buried debris

Archaeological Sites Investigation

IP and Resistivity

Induced Polarisation (IP) is a technique of measuring an induced potential field in the ground in order to map the geological subsurface. From measurements of the induced potential field the chargeability and resistivity of the subsurface can be calculated.

These measurements are made in either the time domain or frequency domain using various configurations of transmission electrodes and multiple potentiometer receivers.

Mineral Exploration

Groundwater Mapping

Geological Stratigraphy Mapping

Mapping of Fault Structures

Archaeological Site Investigation

High Sensitivity Magnetics

Magnetic techniques measure disturbances in the earth's natural magnetic field. These disturbances are caused by ferromagnetic materials, either magnetic rocks (usually bedrock) or man made objects containing iron or steel.

Mineral Exploration

Mapping of Environmental Targets (UST’s, etc.)

Geological Stratigraphy Mapping

Archaeological Site Investigation

Frequency Domain EM Surveys

Frequency Domain Electro-Magnetic induction (FDEM) involves generating an electromagnetic field which induces current in the earth which in turn causes the subsurface to create a magnetic field.  By measuring this magnetic field, subsurface properties and features can be deduced.

Mineral Exploration

Groundwater Mapping

Geological Stratigraphy Mapping

Seismic Refraction and Reflection Techniques

In seismic refraction surveys, a very small seismic wave is generated in the ground by either a hammer or small explosive change.  This wave is refracted in the subsurface and detected by a series of sensitive geophones deployed along the ground.  By measuring the travel-times of the seismic waves, the nature of and depth to subsurface features can be computed.

In seismic reflection surveying, the seismic wave is reflected from the subsurface layers and detected by the geophones on the surface.

Geotechnical Investigations (including bedrock hardness)

Petroleum Exploration

Mineral Exploration

Borehole Logging

Geophysical borehole logging involves the lowering of probe which measures the physical property of the rocks thus determining changes in rock type and areas of mineralisation, etc.

Mineral Exploration

Uranium Exploration

Groundwater Mapping

Geological Stratigraphy Mapping

Radiometrics Surveys

Ground radiometric surveys can be used to rapidly map and target radioactive elements or changes in geology due to the radiometric elements in the different rock types.

The radiometrics survey can also be used in the environmental field for determining the extent and strength of a radioactive contamination in the subsurface.

Mineral Exploration

Uranium Exploration

Environmental Contamination Pollution

Geological Stratigraphy Mapping

Archaeological Site Investigation

Gravity Surveys

A gravity survey measures very small changes in the earth gravitation field which are related to the density of rock.  The density of the rocks can provide detail of the basement depths and detect voids in the sub-surface.

Mineral Exploration

Petroleum Exploration

Geothermal Resource Mapping

Mapping Geological Structures