Radiogeochemical and petrochemical characteristics of eclogites and eclogite-like rocks of Northern Kazakhstan

Behaviour of radioactive elements in eclogites and eclogite-like rocks in the Northern Kazakhstan was studied. Uranium and thorium in samples were detected by neutron activation, X-ray spectral and alpha track methods. It is shown that the lowest uranium and thorium concentrations are observed in unchanged rocks and, when changing rocks, U and Th contents in gabbro-diabases increase 3-6 times, in diaphthorite eclogites - 10 times; in Mg-Fe-Ca metasomatites a high thorium-uranium ratio equal to 7.7 is noted. The conclusion of possibility of U and Th use as indicators during separation of eclogites and eclogite-like rocks similar in compositions but different in origin and as a criterium for search is drawn