Implementation of FLUKA for γ-ray applications in the marine environment

The FLUKA code was implemented to simulate pulse-height spectra of a NaI(Tl) detector (excluding its resolution), considering radioactive sources of naturally occurring and artificial radionuclides present in the marine environment. For this purpose, a user-defined routine was developed for the proper simulation of the emitted γ-rays. The results were compared with simulations performed using the MCNP-CP code. The comparison of the recorded counts in the full-energy peaks, for the high intensity (emission probability >15%) emitted γ-rays for each radionuclide, yielded a satisfactory agreement (calculated ratios from 0.93 ± 0.05 to 1.07 ± 0.02) in all the studied cases

Uranium-bearing phosphatized limestones of NW Greece

Sedimentary Mesozoic rocks from NW Greece (Epirus region), and particularly laminated phosphatized limestones, bedded chert-rich limestones and brecciated phosphatized limestones, were examined for their actinide content. Gamma-ray measurements using a HPGe detector showed that the above geological materials exhibit high radioactivity, mainly attributed to the 238U-series. The 238U content (up to 7700Bq/kg) was determined by the 1001keV photopeak of 234mPa, the 238U daughter. Bulk geochemical analyses using ICP-OES/MS showed variable U concentrations with a notable value of 648ppm in the case of dark organic-rich material hosted into the brecciated phosphatized limestones. Relatively high concentrations of Cd, probably related to apatite, were also revealed. On the other hand, the rock is geochemically depleted in LILE (e.g. Cs, Rb, K), as well as in As, Sb and Se in contrast to "average phosphorite". Powder-XRD combined with optical microscopy, SEM-EDS and FTIR confirmed abundant apatite, besides calcite, as well as organic compounds (organic matter/O.M.) which should be associated to the high U content. According to Th/Sc vs. Zr/Sc discrimination diagrams the organic-rich part of the U-bearing phosphatised limestones exhibits a mafic trend, in contrast to the rest of the studied rocks lying close to typical pelagic sediments. However, Eu/Eu* vs. Ce/Ce* diagrams, in combination with SEM-EDS, indicated that the organic-rich part is a typical sedimentary material whereas the organic-poor (and also U-poor) part of the rock is secondary calcite related to surface waters. As far as we know, the studied rocks from NW Greece are classified as among the richest U-bearing phosphatized limestones and/or sedimentary phosphorites in the world. © 2014 Elsevier B.V

USING ENVIRONMENT TRACERS FOR INVESTIGATION OF BLACK SEA POLUSHION

In order to determine the groundwater discharge (SGD) areas into the sea during studies had been implemented and selected the new methodology of using ecological tracers, such as stable isotopes 18O and 2H, radionuclide Rn and Ra and other parameters. On the territory of Kobulety had been defined the groundwater flow direction and the areas of their submarine discharge. Within the identified areas was defined the intensity of eutrofication –the value of nitrate and phosphate content in groundwaters and in the sea. Also, had been studied their distribution on the surface and intensity of outwash into the sea