Proterozoic mafic magmatism in Siberian craton: An overview and implications for paleocontinental reconstruction
2010; Elsevier BV; Volume: 183; Issue: 3 Linguagem: Inglês
10.1016/j.precamres.2010.02.023
ISSN1872-7433
AutoresД. П. Гладкочуб, Sergei Pisarevsky, Т. V. Donskaya, Richard E. Ernst, M.T.D. Wingate, Ulf Söderlund, А. М. Мазукабзов, Е. V. Sklyarov, Michael A. Hamilton, J. A. Hanes,
Tópico(s)Geochemistry and Geologic Mapping
ResumoWe present a summary of late Paleoproterozoic to Neoproterozoic mafic magmatism in the Siberian craton, including recently published U–Pb and 40Ar–39Ar dates. These new precise ages suggest that at least some of the previously published K–Ar ages of Siberian mafic bodies should be ignored. The time–space geochronological chart, or the ‘barcode’ of mafic magmatic events shows significant differences between northern and southern Siberia. Both are characterized by ∼1900–1700 Ma magmatic events, but then there was an almost 1 Ga mafic magmatic ‘pause’ in south Siberia until ∼800 Ma. Meanwhile there are indications of multiple mafic magmatic events in North Siberia (Anabar shield and Olenek uplift) between ∼1600 and 1000 Ma. A series of magmatic events probably related to the breakup of Rodinia occurred in southern Siberia after ∼800 Ma. So far, there are no indications of late Neoproterozoic mafic magmatism in North Siberia. Ca. 1000–950 Ma mafic sills were reported from Meso- to Neo-Proterozoic sedimentary successions in the Sette-Daban area on the east side of the Siberian craton, but their tectonic setting is debated. Recent Ar–Ar dates of ∼1750 Ma for NW-trending dykes in the Aldan and Anabar shields, together with similar-age NNE-trending Baikal uplift dykes in south-eastern Siberia suggest the existence of a giant radial dyke swarm possibly related to a mantle plume centred in the Vilyui River area.
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