Место издания:SLOVENSKA PLAZA, BUDVA, MONTENEGRO BUDVA, MONTENEGRO
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Аннотация:The natural hazard on some seashores is the so-called "black" or monazite sands, which are radioactive sands formed naturally by geological processes. The main radioactive elements in them are 232Th, 238U and their decay products. There are many coastlines in the world which are known to have radioactive objects (India, Brazil, Sri Lanka, etc. [1]), while similar radioactive deposits of the White Sea, the Sea of Azov, and partly Black Sea are hardly described. The presence of radioactive sands is often confined to the crystalline massifs. For instance, White Sea sands are due to the Baltic Shield, and the sands of Sea of Azov are due to the Ukrainian crystalline shield. The exposure dose in the places of "black sand" accumulations on the seashoes investigated are 0.05 - 0.3 mR/h on average, but may reach as high as 0.9 - 1.0 mR/h in some deposit placers during some years. Chemical, mineralogical and grain-size analyses of the radioactive sands as well as gamma spectrometry and analysis of their radioactive emanations were carried out [2]. The dependence of the radiation background of the coast on the meteorological parameters was also studied [3]. Radioactive deposit placers of the White Sea are not a serious environmental hazard due to the low population density and the absence of vacationers. On the other hand, the northern shores of the Black Sea and the Sea of Azov are unique as they have the "black sands", and strong winds in the areas of high population density and a great number of vacationers. The absence of even one of these factors would remove the problem or, at least, make it irrelevant, but their simultaneous acting creates a situation which is extremely dangerous and has no analogues. While it is not possible to ignore the hazard of the “black sands,” it is not necessary to ban the whole coastline for public recreation. It is enough to detect all the localizations of black sands, to control them and to carry out protective measures [4]. One must also bear in mind that not all the "black sands" of the seas are radioactive. Azov Scientific Research Station (ANIS) is a joint project of the Lomonosov Moscow State University of Russia and the Azov State Technical University of Ukraine. The Azov Station has been carrying out research on the shores of the Sea of Azov, Black and White Seas since 1996. The Department of Radiochemistry of the Chemistry Faculty of Lomonosov Moscow State University was the initiator and main organizer of the ANIS. The priorities of ANIS work are the following: radio-ecological marine studies, geomorphology of coasts, and marine geology. [1] Freitas A.C., Alencar A.S. // J Env Rad 2004. V.75. p.211–223 [2] Ryazantsev G.B., Khaskov A.V. et al // Proc. of the Int. Conf. “Ecological and institutial mechanisms of the managements of the seaside regions and marine ecosystems”, Mariupol, Ukraine, 2001, p.53-54 [3] Beckman I.N., Khaskov M.A. et al // Mos Univ Chem Bull, 2003, v.44, №–2, p.140-148 [4] www.secology.org