文摘
We present a summary of late Paleoproterozoic to Neoproterozoic mafic magmatism in the Siberian craton, including recently published Ux2013;Pb and 40Arx2013;39Ar dates. These new precise ages suggest that at least some of the previously published Kx2013;Ar ages of Siberian mafic bodies should be ignored. The timex2013;space geochronological chart, or the x2018;barcodex2019; of mafic magmatic events shows significant differences between northern and southern Siberia. Both are characterized by 1900x2013;1700 Ma magmatic events, but then there was an almost 1 Ga mafic magmatic x2018;pausex2019; 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. 1000x2013;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 Arx2013;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.