Density Tool - Single Point

Parameters Logged:

Density

Focused Scintillation Crystal 12.7 mm x 38.1 mm

0.5 – 6.0 g/cc

Natural Gamma

Scintillation Crystal 22 mm x 102 mm

0 - 10,000 API units

3 Element Guard Resistivity

101.6mm centre electrode, 1410mm guard electrode

0 – 40,000 ohm metres

Calliper

Motorised

0-300mm (long arm)

This tool was specifically developed for use in high density environments (eg. iron ore). The tool focuses high energy gamma radiation from a Cobalt 60 source into the formation. The gamma rays interact with the formation via Compton scattering and are then backscattered to the detector. Photons in the photoelectric range are filtered out by the tool before reaching the detector to improve the accuracy of density readings. The photons reaching the detector are used to determine apparent bulk density. The determination of bulk densities is therefore considerably more accurate. The tool can also be used in lower density environments (0.5-3.5g/cc) with a Caesium 137 source.

As well as density the tool measures natural gamma, bore hole calliper (bore hole diameter) and medium guard resistivity. Medium guard resistivity offers excellent vertical resolution and is well suited to more saline environments.

Applications:

The tool can be used in steel casing/drill rods or in the open hole. Reliable porosities can only be achieved in the open hole.

The most common applications are:

• Bulk density measurement (ore and overburden tonnage)
• Lithology
• Bed thickness and boundary location
• Mineralised zones
• Long term water well monitoring (salinity)
• Rock strength and elasticity parameters (combined with sonic log)

Example Log Image: