Geochemistry of uranium and thorium and natural radioactivity levels of the western Anatolian plutons, Turkey

• Published in: Mineralogy and petrology Vol. 111; no. 5; pp. 677 - 691
• Main Authors: Papadopoulos, Argyrios, Altunkaynak, Şafak, Koroneos, Antonios, Ünal, Alp, Kamaci, Ömer
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.10.2017; Springer Nature B.V
• Subjects: Color; Colour; Composition; Differentiation; Earth and Environmental Science; Earth Sciences; Geochemistry; Inorganic Chemistry; Magma; Mineralogy; Natural radioactivity; Original Paper; Plutons; Radioactivity; Radioisotopes; Radionuclide kinetics; Radium isotopes; Radium radioisotopes; Spectrometry; Thorium; Trace elements; Uranium; Turkey; Uranium; REEs; Western Anatolia; Granite; Thorium
• ISSN: 0930-0708; 1438-1168
• DOI: 10.1007/s00710-017-0492-4

Seventy samples from major plutons (mainly granitic) of Western Anatolia (Turkey) have been analyzed by γ-ray spectrometry to determine the specific activities of 238 U, 226 Ra, 232 Th and 40 K (Bq/kg). Τhe natural radioactivity ranged up to 264 Bq/kg for 238 U, 229.62 Bq/kg for 226 Ra, up to 207.32 Bq/kg for 232 Th and up to 2541.95 Bq/kg for 40 K. Any possible relationship between the specific activities of 226 Ra, 238 U, 232 Th and 40 K and some characteristics of the studied samples (age, rock-type, colour, grain size, occurrence, chemical and mineralogical composition) was investigated. Age, major and trace element geochemistry, color, pluton location and mineralogical composition are likely to affect the concentrations of the measured radionuclides. The range of the Th/U ratio was large (0.003–11.374). The latter, along with 226 Ra/ 238 U radioactive secular disequilibrium, is also discussed and explained by magmatic processes during differentiation.