PLATINUM GROUP ELEMENTS IN THE SOUTH TRANSBAIKALIAN BASANITES (first data)
A.Ya. Medvedev, A.A. Karimov, V.A. Belyaev
Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, Irkutsk, Russia
Keywords: Alkali basaltoids, PGE, basanites, plume, southern Transbaikalia
Abstract
Study of the behavior and distribution of platinum group elements (PGE), along with other data, is necessary for geodynamic reconstructions. There are almost no PGE data for Transbaikalia, one of the large regions of Russia. This work presents the first data on the contents and behavior of PGE in the Cenozoic intraplate alkali basaltoids of southern Transbaikalia. The total PGE contents are 20-40 ppb. The PGE pattern of the studied basanites is similar to those of mafic OIB, including the Hawaiian ones, and rocks of large igneous provinces: tholeiitic basalts of the Siberian Platform and basaltoids of the West Siberian Plate. Based on this similarity and on the intraplate location of the South Transbaikalian basanites, we have concluded that the basanitic melts formed under mantle plume impact.
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