Geophysical well logging is one method to acquire detailed information about the geometrical (size, position), physical and lithological characteristics of the subsurface geological layers and the water they contain.
This is achieved using one specific measuring tool, lowered inside one water well and pulled upwards with constant speed. The tool measures many physical parameters of the geological layers and transmits them to the surface through one cable.
One computer in the surface collects the signals together with the exact depth information and this record is described as one geophysical log.
The most common geophysical well logs include the measurement of the resistivity of the geological layers, the temperature of the water, the natural gamma ray radiation, the vertical water flow, the conductivity of the water and other. Using one combined interpretation, many useful information can be extracted about the subsurface layers.
ADVANTAGES OF THE WELL LOGGING
The wells must be constructed in one way, to “fit” in the layers drilled in the column. The “well logging” method is the only way to achieve this task. It helps to create wells with higher water quality and with a long production life.