A034 Induction Conductivity Tool 38mm

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Tool Description

Conductivity is the inverse of resistivity. Induction logging systems were originally designed to facilitate resistivity measurements in oil-based drilling mud, where there is no conductive medium between the tool and the formation. It is also often used in dry holes or when the borehole fluid is very fresh. The purpose is, as usual, to measure resistivity or conductivity in order to calculate porosity and to interpret lithology. Induction is useful in several types of ground investigation.

The A034 Induction, Conductivity tool is designed for the measurement of electrical conductivity of rocks in boreholes. High stability and exceptionally wide dynamic range permit precise measurements of conductivity of sand-clay layers and also mineralised water-soaked sands. The tool may be used in water filled, dry and plastic cased boreholes. The response of the probe is practically instantaneous (<0.5 s).

This tool is used for high sensitivity, 1 to 300mS/m is intended to suit the
requirements of those concerned with relatively low conductivity. A tool with an extended range is also available. See A034E for more information.

This tool is also available in combination with Natural Gamma or Magnetic Susceptibility. Click here for more information.

Ground Water Investigation

The resistivity of rocks depends on several factors. Rocks are usually poor conductors. Rock resistivity is determined, primarily, by porosity and the salinity of the pore fluid.

Clay minerals reduce the resistivity of the formation. Some alteration processes result in the formation of clay minerals, reducing resistivity, while others reduce rock porosity and increase formation resistivity. Decreases in resistivity may be a result of either significant concentration of conductive metal sulphides or oxides. Fracturing increases effective porosity and can, therefore, decrease resistivity.

The complexity of resistivity interpretation means that complementary information from other geophysical measurements or other geological logs is usually required. However, massive sulphide deposits generally consist of conductive ore zones and resistivity logs are often used to delineate these ore zones.

Mineral Investigation

The resistivity of rocks depends on several factors. Rocks are usually poor conductors. Rock resistivity is determined, primarily, by porosity and the salinity of the pore fluid.

Clay minerals reduce the resistivity of the formation. Some alteration processes result in the formation of clay minerals, reducing resistivity, while others reduce rock porosity and increase formation resistivity. Decreases in resistivity may be a result of either significant concentration of conductive metal sulphides or oxides. Fracturing increases effective porosity and can, therefore, decrease resistivity.

The complexity of resistivity interpretation means that complementary information from other geophysical measurements or other geological logs is usually required. However, massive sulphide deposits generally consist of conductive ore zones and resistivity logs are often used to delineate these ore zones.

Coal Investigation

Coal usually has high resistivity. This may be reduced according to its porosity, clay, and water content. The porosity of coal varies with rank and so its resistivity increases from lignite to semi-anthracite and then decreases slightly with anthracite. Clay inclusions reduce the resistivity of coal.

Clay-rich lithologies, such as shales, have low resistivity. Clean, relatively dry sandstone has high resistivity. This may be reduced according to porosity, salinity, and clay content.

Resistivity (or conductivity) logs may also indicate oxidation of a coal seam or alteration by an intrusion.

FEATURES
Convenient and simple to use
High sensitivity
MEASUREMENTS
Resistivity or Conductivity
APPLICATIONS
Coal, Ground Water	Mineral detection
OPERATING CONDITIONS
Borehole type	Borehole type: open-hole, water-filled
TOOL SPECIFICATIONS
Diameter	38 mm / 1.496 in
Length	1400 mm / 55.118 in
Weight	5 kg / 11.023 lb
Min. Temperature	0ºC / 32 ºF
Max. Temperature	70ºC / 158ºF
Max. Pressure	10 000 kPa / 1450 psi
Tool Voltage Required	30 VDC
Tool Current Required	80 mA
Communications	Pulse
Cable Conductors Required	1 or 4
SENSORS
Conductivity/Induction	Two Coil System
Inter-coil Spacing	500 mm / 19.685 in
Operating Frequency	~26kHz
Conductivity Range	1 - 300 mS/m
Noise Level	<0.5 mS/m
SHIPPING SPECIFICATIONS
Length	1500 mm / 59.055 in
Width	120 mm / 4.724 in
Height	120 mm / 4.724 in
Weight	7 kg / 15.432 lb
SALES INFORMATION
Click here to contact sales for more information

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