The A606 Micro Density tool, utilises a radioactive SOURCE SO SMALL that a Radiation Licence is NOT A REQUIREMENT in many locations. The source strength is less than 1% of that used in the conventional density tool. The MICRO DENSITY has already found application with the Coal industry in Australia and Overseas, providing Geophysical logs of very high resolution which compares favorably with conventional tools. Ideal when used in combination with the A631 Gamma. Combination A619 available - Micro Density/PR/Caliper/Gamma. Usually the tool is run decentralised (often in conjunction with a single-arm caliper) and both the source and detector are collimated. These features minimise the influence of drilling mud and caving.
Density/Gamma
The density tool or gamma-gamma log contains both a source of gamma radiation, and a gamma detector.The proportion of gamma rays emitted by the source and back-scattered to the detector is a measure of the density of the formation in the vicinity of the source/detector combination.
Different source-detector spacing may be used, for example to maximise thin bed resolution, or to improve the accuracy of the density calibration.
Gamma information is available by viewing the following tools A031, A631, A075, A675 and A088.
Caliper
The caliper provides quantitative information about hole-diameter. The caliper is an electromechanical unit that, by use of a spring-loaded arm, gives a measurement of borehole diameter. Knowledge of borehole diameter can be used to correct the response of the density log that is sensitive to borehole diameter. It can also provide an indication of the mechanical properties of the rocks by showing areas of caving.
Applications
Coal
The unusually low density of coal means that it may be identified readily by the density tool. The actual value of the density is an indication of the ash content. Thin ash bands and seam splits may be easily discerned
Iron ore
In iron ore exploration, ore density is a useful measure of iron content.
Groundwater exploration
For groundwater exploration strata density can be related to porosity. Legislative requirements may preclude the operation of conventional density logs water bores.
Engineering
Engineering applications use the density log as a reliable indicator of rock strength. Factors such as weathering, fracturing and porosity can be evaluated - these seriously affect mining and excavation characteristics. Quantitatively, density can be allied to such strength parameters as Poisson's ration. Generally thin but often critically important strata such as volcanic ash and carbonates, can be identified.
Mineral related exploration
Quantitatively, density can be allied to such strength parameters as Poisson's ratio. Generally thin but often critically important strata such as volcanic ash and carbonates can be identified.
Contact Auslog for further information.
FEATURES
Density output in g/cc
Dual Detectors, Short Spaced and Long Spaced
Strong Caliper Arm for borehole contact
High Quality Collimation
Natural Gamma Included
MEASUREMENTS
SSD, LSD, Caliper, Natural Gamma
APPLICATIONS
Water
Location of Aquifiers and indications of porosity + others
Engineering
Ground Compaction, weathered zone detection, rock strength + others
Minerals
Bed Thickness, Ash content of coal, density units, correlation + others
OPERATING CONDITIONS
Borehole type
Open-hole, Water Filled, potential in some cased hole/ airsituations
