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Vestnik Otdelenia nauk o Zemle RAN, VOL. 6, NZ2001, doi:10.2205/2014NZ000122, 2014

Middle Paleozoic volcanism of the Omolon Massif (Northeast Asia): Chemical composition and geodynamic interpretation problems

A. M. Gagieva

North East Interdisciplinary Research Institute, Far East Branch, Russian Academy of Sciences, Magadan, Russia


Abstract

The all known data on the chemical composition (170 complete silicate analyzes and 120 analyzes of trace elements: Rb, Sr, Y, Zr, Nb) of Middle Paleozoic subaerial volcanic rocks of the Omolon Massif, which is a tectonic element of Northeast Asia (craton terrane or paleo microcontinent) with unique duration of geological history, are summarized. Geochemical features of the Middle Paleozoic volcanism have been studied at the structure level of second and third order with respect to the Omolon Massif as a whole. On this basis, the revision of popular methods of geodynamic reconstructions is held. The studied volcanics belonging to the same stratigraphic unit (the Middle Paleozoic Kedon Group), appear on discriminatory diagrams in some cases as derivatives of island arc, in others – of continental margin, in the third – of intraplate magmatism etc. The conclusion about imperfection of popular tools of geodynamic reconstructions is done. The reliance on analytical characteristics only of the modern magmatic objects as standards for the remote geological past is a major source of errors.

Received 24 October 2014; published 27 November 2014.


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Citation: Gagieva A. M. (2014), Middle Paleozoic volcanism of the Omolon Massif (Northeast Asia): Chemical composition and geodynamic interpretation problems, Vestn. Otd. nauk Zemle, 6, NZ2001, doi:10.2205/2014NZ000122.

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