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The activity concentrations of 222Rn with an AlphaGUARD system in well having different depths and in natural spring waters were measured to assess the natural radioactivity level of the Çorlu region. The measured concentrations varied from 22.04 to 63.92 Bq L−1 for 6 well water samples, 15.38–24.33 Bq L−1 for 6 spring water samples. The activity concentrations from 238U, 232Th and 40K in 11 soil samples collected from the same region were also determined and the outdoor gamma dose rates at 1 m above the surface at the same sampling points were measured. The results obtained in this study lie within safe limits recommended by WHO and UNSCEAR with the exception of the mean specific activity of 40K radionuclide. © 2021, Akadémiai Kiadó, Budapest, Hungary.

Dissolution kinetics of nickel from lateritic ore in nitric acid solution was investigated. Experimental parameters used were stirring speed (100-600 r/min), temperature (40-96 °C), nitric acid concentration (0.1-2 mol/L) and particle size (

Mafic microgranular enclaves (MMEs) are widespread in the Horoz pluton with granodiorite and granite units. Rounded to elliptical MMEs have variable size (from a few centimetres up to metres) and are generally fine-grained with typical magmatic textures. The plagioclase compositions of the MMEs range from An18–An64 in the cores to An17–An29 in the rims, while that of the host rocks varies from An17 to An55 in the cores to An07 to An33 in the rims. The biotite is mostly eastonitic, and the calcic-amphibole is magnesio-hornblende and edenite. Oxygen fugacity estimates from both groups’ biotites suggest that the Horoz magma possibly crystallised at fO2 conditions above the nickel–nickel oxide (NNO) buffer. The significance of magma mixing in their genesis is highlighted by various petrographic and mineralogical characteristics such as resorption surfaces in plagioclases and amphibole; quartz ocelli rimmed by biotite and amphibole; sieve and boxy cellular textures, and sharp zoning discontinuities in plagioclase. The importance of magma mixing is also evident in the amphiboles of the host rocks, which are slightly richer in Si, Fe3+ and Mg in comparison with the amphiboles of MMEs. However, the compositional similarity of the plagioclase and biotite phenocrysts from MMEs and their host rocks suggests that the MMEs were predominantly equilibrated with their hosts. Evidence from petrography and mineral chemistry suggests that the adakitic Horoz MMEs could be developed from a mantle-derived, water-rich magma (>3 mass%) affected by a mixing of felsic melt at P >2.3 kbar, T >730°C.