Radon Risks Evaluation and Application in the Assessment of Tremor-Prone Areas

In just a time span of 5 years, northcentral Nigeria has experienced about three earth tremors. Public commentators were quick to attribute the tremors to the over-abstraction of groundwater and construction activities in the area. This study sets out to investigate the cause of tremors in the study area and develop a scientifically viable method that predicts areas prone to earth movement in the event of future tremors using integrated techniques (geophysical, hydrogeological, nuclear, and GIS). The results obtained confirmed the incidences of tremors in parts of northcentral Nigeria. Field and other evidence obtained suggest that the tremors were caused mainly by quarry activities in parts of the area. This suggestion was corroborated by results obtained from the surface manifestation of movements, radon in the groundwater, quarry proximity, slope, etc. Also, the study discovered substantial radiological implications associated with radon in groundwater because of earth movement. It also confirmed as baseless the notion of associating the tremors in the area with the over-exploitation of groundwater. Finally, the study came up with a method that predicts areas prone to earth movement in the event of future tremors in the area and categorized them based on their likelihood of experiencing movement as highly likely, likely, and not likely.