Investigation of an aerospectrometric anomaly using ground gamma ray spectrometry sheet 81, Dutse North-Western Nigeria

Abstract

Ground radiometric survey carried out at Gaya North-Western Nigeria using Portable 
Gamma-ray Spectrometer confirmed, characterized the observed anomalies in Aerospectrometric map and then correlated with Geological map. The area lies between 
Longitude 9° 21' 5.63"-9° 21' 38.57" and Latitude 11° 44' 10.59"-11° 44' 43.53". Twenty 
one profiles each 1 km long and 50 m apart were laid having total of 441 stations. Station 
coordinates were identified by global positioning system. The meas time was set at 3 min
utes for valid order of 0.1% for K and 1 ppm for eU and eTh concentration. Both map 
grids and statistical analysis was applied to the acquired data. The research revealed mean 
concentration of the radioelements-U, Th, and K as 17.527 ppm, 59.06 ppm, and 4.1092%, 
respectively, in the order of (Th > U > K), absorbed does rate values ranging from 33.45 to 
676.49 nGyph−1 with average value of 48.3 nGyph-1 is lower than the world average value. 
Correlation of 0.9, 0.8, and 0.82 for (238U and 232Th), (40K and 238U), and (232Th and 40K), 
respectively, were obtained. The research identified rocks associated with these radioele
ments, thorium being major source of radioactivity and serve as awareness to the citizens.