%0 Journal Article
%T Middle Paleozoic-Mesozoic boundary of the North Asian craton and the Okhotsk terrane: new geochemical and geochronological data and their geodynamic interpretation
%A V. A. Trunilina
%A P. W. Layer
%A L. M. Parfenov
%A 
%A A. I. Zaitsev
%A Y. S. Orlov
%J Stephan Mueller Special Publication Series (SMSPS)
%D 2009
%I 
%R 10.5194/smsps-4-97-2009
%X The Tommot pluton is located within the continental Omulevka terrane of the inner zone of the Verkhoyansk-Kolyma Mesozoic orogen. It is a small complex (~12 km2) composed of alkaline-ultramafic rocks, alkaline and subalkaline gabbroids, and alkaline and quartz syenites. The pluton is unique both in the composition and age of its constituent rocks. Mineralogical-petrographical and geochemical studies of the rocks indicate that the alkaline rocks resulted from the melting of depleted mantle horizons. K-Ar, Rb-Sr, and 40Ar/39Ar age determinations confirm a Paleozoic age of the rocks. Formation of the alkaline rocks is related to Middle Paleozoic rifting which occurred as two discrete events: a Late Devonian event, which affected the marginal part of the Siberian continent, and a Late Carboniferous event that reflects internal deformation of the Omulevka terrane or late-stage extension. A spatially associated alkali granite, the Somnitel'nyy pluton, is Late Jurassic¨CEarly Cretaceous in age and is synchronous with accretion of the Kolyma-Omolon Superterrane to Siberia in the Mesozoic.
%U http://www.stephan-mueller-spec-publ-ser.net/4/97/2009/smsps-4-97-2009.html