EMANOMETRY DETECTION OF RADON ABNORMAL CONTACTS MASKED IN THE PLAIN OF GHARB (MOROCCO)

Radon is a colorless and odorless radioactive gas resulting from the decay of uranium and radium. It gains its source in the earth's crust. Its emanation from the ground surface varies from one point to another depending on the physical characteristics of the terrain crossed. A dosimetry study of the Radon emanations in the “Gharb's plain” revealed strong fluctuations in the concentrations of this gas along transverse orientations to the possible deep abnormal contacts. To seal these contacts, we have implemented a series of radon detection stations throughout a cut with a very specific step. The revelation of the dosimeters (LR115) and the counting of detected traces showed a more or less homogeneous distribution except in the vicinity of the possible fault. The appearance of this distribution in the form of an open bell is linked to a probable wide diffusion of gas in the soil of the “Gharb's plain” (Tirs). This diffusion can also be associated with the depth of the radon emanation source (deep abnormal contact).