Using of a Moran’s I and Hot Spot Analysis to Identify of Thoron in Najaf City using GIS Software

Document Type : Original Research Paper


1 University of Kufa, Faculty of Dentistry, Department of Basic Science, Al-Najaf, Iraq

2 University of Kufa, Faculty of Science, Department of Physics, Al-Najaf, Iraq


AGIS method based on spatial autocorrelation analysis used to identification and ranking of thoron (220Rn)concentration. Spatial radiation patterns are analyzed using Moran's I statistic. Getis-Ord Gi* is utilized to locate clusters of high and low measurements and create a map of thoron hot spots. One hundred schools in the center of Najaf City were examined for thoron using CR-39 detectors (produced from Track Analysis Systems Ltd., UK)  for this research. Average thoron levels were 2.99 Bq/m3, with a range of 9.00 Bq/m3 to 0.22 Bq/m3. The radiation levels found in this investigation were significantly lower than the UNSCEAR 2000 safety standards of 40 Bq/m3. Moran's, I have used it to analyze the clustering of districts across a research region and to measure the spatial distribution of data. Getis-Ord Gi* statistics were used to identify cold and hot spots within the research area. Thoron concentrations were shown to have insignificant spatially random distribution patterns, as demonstrated by Global Moran's I. (Moran’s I =0.28, p-value=0.24). 


Main Subjects

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