Spatial risk analysis of lignite radioactivity concentrations with GIS and remote sensing (case study of Türkiye coalfields).

Radioactive elements in coals may have high concentrations and could reach higher radioactivity levels when the coals are burnt. In this study, the elemental geochemistry of lignites from Tekirdağ-Karaiğdemir, Manisa-Soma, Kütahya-Tunçbilek, Adıyaman-Gölbaşı lignite fields with high reserves was examined, radionuclide concentrations were determined, and radiological risk assessments were made. The calculated average ²²⁶Ra, ²³²Th and ⁴⁰K concentrations were analyzed for 48 samples taken from four sites and the measured U, Th, Pb and K concentrations were compared with world coals, Turkish coals and Upper Continental Crust (UCC). It was determined that the natural radioactivity concentration levels of the Manisa-Soma coalfield could pose a radiological risk. The high concentration of U (41.4 mg/kg) in Manisa-Soma coals and the high concentration of Th (14.9 mg/kg) and K (0.8 %) in Kütahya-Tunçbilek coals have a strong positive correlation with ash yield and their formation patterns suggest the origin of these elements are inorganic. In addition, the findings were analyzed in 7 different classes (Water, Trees, Flooded Vegetation, Crops, Built Area, Bare Ground, Rangeland) in terms of environmental risk factors using Geographical Information System (GIS) and Remote Sensing methods using Land Use Land Cover (LULC).