GeoPhysics

HomeCapabilitiesGeoPhysics

Dr Jim CullJim Cull

Dr Jim Cull (AM), Professor Emeritus from Monash University and ourselves have come together to provide Geophysical field surveys, and to continue to develop the technology that he has pioneered.

Jim has studied all aspects of the earth’s physical properties and the physical processes acting upon, above, and within it. He has been a world leader in NDT technologies since 1986.

Our assessment programs provide key input for asset replacement &/or remediation strategies, and the prioritisation of the maintenance of critical assets.

Particular emphasis is placed on high resolution methods for:

  • Water
  • Mining
  • Oil & Gas
  • Rail
  • Environmental
  • Engineering/Construction
  • Electricity
Our reports provide a risk-based, predictive, analysis for asset management of:

  • Pipelines
  • Bridges
  • Underground Service Tanks, etc.
 
 
 
 
 
 
 

 
 
 
 

Instrument R&D Program

We have a strong R&D program aimed at developing new products, improving the technology in existing products, and improving the processes used in the field. Our aim is to can provide the best instrumentation available to the industry

Currently we are investigating methods for assessing cement pipes, and cement lined pipes. This work is yielding very positive results. We are also in the final stages of commercialising a new instrument for measuring the wall thickness of ferrous pipes using eddy current sensing.
 

Key Technologies

We have developed the next generation of Broadband ElectroMagnetics called TEM (Time-domain ElectroMagnetics).

It is used as a back up to GPR, used for groundwater mapping, pollution plumes, depth to base

Transient Electromagnetics – soil corrosivity, wall thickness

Open field applications used in same way as magnetic; responds to electrical rather than magnetic (eg groundwater, soil type, rock etc); cousin to GPR because provides vertical image.

Used extensively in mineral exploration, geotech and environmental such groundwater mapping etc.

LPR (Linear Polarised Resistivity) is an in-field sampling technique for spot analysis of corrosivity in soils; samples are gathered in the field and analysed in a laboratory. It is ideal for small areas and hard to get at places.

As LPR has limitations in that it cannot provide entire soil signature across a large area, we have developed a more accurate and robust technique that is complimentary to traditional method – it has no direct equivalent.

Whilst LPR instrumentation uses off-the-shelf equipment our LPR system is the only one of its kind that uses synthetic standards, which is crucial for quality assurance. We use numerical analysis and equivalent circuit theory, providing data of the highest precision. It is the only technique that is sensitive to electrochemical activities associated with corrosion.

This technique adds additional information from resistivity, LPR and stray current corrosion to detect areas that are susceptible to accelerated areas of electrolysis.

It is much faster than traditional LPR methods and can cover greater areas in less time. It interrogates large volumes of pipe bedding obtaining continuous data samples, thus sampling entire pipe volume without being subjected to sampling error.

It cannot be used in confined spaces or those that are not easily accessible.

HDU (High Definition Ultrasonics) introduces high frequency sound waves into a test object to obtain information about the object without altering or damaging it in any way.

HDU is non-destructive testing technique for measuring metal thicknesses and variations.

Two basic quantities are measured in ultrasonic testing; time of flight (the time required for the sound to travel through the sample), and the amplitude of the received signal. Based on a velocity calibration and round-trip time of flight through the material a thickness can be readily calculated. However any variations in the material properties including changes in temperature can affect sound velocity and consequently the accuracy of any thickness measurements.

User for:

  • Corrosion work
  • Defect analysis such as integrity of storage tanks

For pipeline corrosion analysis we use equipment that can accommodate a wide range of materials with different acoustic impedances. In particular it provides a clear visual display of reflection signals which can be immediately assessed for false echoes from internal granularity. In addition it provides for on-site calibration using standard step blocks to ensure instrument precision.

HDU is limited in that full surface preparation is required – must have intimate contact with surface (all coatings must be removed).

GPR (Ground Penetrating Radar) is a standard geotechnical tool with high definition and high resolution, that is relatively easy to deploy. It provides a ‘depth image’ to locate underground structures such as tanks, changes in soil signatures.

  • Used for locating objects underground (tanks, changes of soil signatures, etc)
  • Provides high definition, high resolution, and depth of object
  • Relatively easy to deploy
  • Limited with depth of penetration and interference (steel fences, cars, high clay content in soil)
  • Increase in penetration compromises resolution

It does have limitations with depth of penetration and interference (steel fences, cars, etc) and lots of clay limits penetration.

Obviously we provide the basic GeoPhysics tools:

  • Flow Monitoring
  • Pressure Sensing
  • Leak Detection using listening devices
  • Gravity: Scintrex CG3M microgravity
  • Radiometrics: Geometrics G310 Gamma Ray Spectrometer
  • Vibration Analysis
  • Strain Gauging
  • Thermography
  • Susceptibility
  • Porosity
Magnetics: is a standard tool that provides a ‘plain view’ image of entire object underground. While GPR gives vertical image, magnetic gives plain view.

It is good for finding buried infrastructure, even non metallic things.

  • Used for locating buried infrastructure, even non-metallic
  • Gives view of entire object underground
  • Used for subsurface geology (finding geological structure for gold, iron ore, mineral exploration etc)
  • site remediation
Phoenix IP/Resistivity, Scintrex IGS-2/IP-4, OhmMapper
Soil Resistivity
Electrochemical Activity
Substrate Resistivity
CPE-Elorane have devbeloped the Needle Probe, divided bar for measuring Thermal Conductivity??

It us used for Geothermal logging and the location of subsurface pressurised, heated water.

We use QTI and Pt thermistor sensors on 1000m of 4-core cable.

Seismic methods are used for big picture civil engineering projects.

Instrument could be made simpler (long term R&D). Much more expensive than seismic refraction.

Coffeys big in this area. Possible for us to be too.

SASW, 3 component geophones

InfraRed Imaging is used to find faults in items using thermal variations, such as a leak in a pipe where where the fluid inside is changing the outside temperature.