These tools detect natural gamma radiation emanating from the subsurface rocks. Gamma rays are very high frequency electromagnetic radiation and are derived from the radioactive decay of various elements. In borehole
applications the most common radioactive elements are radio isotopes of K, Th,and U. Gamma ray logs provide a clear indication of variations in lithology and also accurately define bed thickness. Shaly bands are obvious and can be readily identifies because clay content results in a high gamma count. The gamma ray log is also used for identification of coal as coal typically exhibits a low count rate. In this application a high sensitivty gamma tool generally provides best results.In petroleum applications the higher the gamma activity of the clay size fraction is due to the potassium contained in clay minerals, fine micas and feldspars. This is not only useful information in its own right, but is a crucial parameter in the accurate interpretation of density and neutron logs. Gamma ray logs are an obvious choice in Uraniam exploration and development. The relationship between uranium content and count rate may be used so that ore grades may be determined in the borehole. Groundwater and engineering applications utilise the gamma ray for lithology indications and strata thicknesses as well as clay content, to determine permeability and rock strength.
A gamma can be incorporated into almost every tool combination.
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Specifications
Diameter A031
A07543mm
33mmSensor NaI Crystal A031
A0751.0x3.0 inch (4PA12)
0.5x1.75 inch (2PA7)Calibration Primary Cal Pits/Jig Length (A31/A75) 1130cm Weight (A31/A75) 4.4 / 3.4 kg Max. Working Temperature 60° C Max. Working Pressure KPg/PSI 21000/3000 Min No. of Cable Conductor 1 Supply Voltage Range 18-45 VDC Nominal 24V Communications Pulse
Auslog