Home – Home – Jornals – Russian Geology and Geophysics 2003 number 12

Periodicity of plume magmatism has been reviewed in this paper. It also demonstrates a correlation between trap magmatism and Permian-Triassic granitoids as well as general regularities of collisional and postcollisional granitoid magmatism and a role of plumes in their manifestation. It has been established that the Permian-Triassic superplume is expressed over vast spaces of Asia in two forms: (a) at places with cold lithosphere in the form of Siberian and Emeishan traps; (b) at places with thickened lithosphere and crust, as a result of preceding collision events, in the form of syenites and A-type granites. Effusions of the Siberian traps and intrusion of associated granitoids are largest-scale events in the Earth's history. At their peaks, the effusions of both Siberian and Ontong Java plumes were about 8-10 x 10⁶ km³ for one myr. Given that gaps between effusions take 90 % of the time, the effusions could reach 100 km³ a year or, with intrusions taken into account, twice as much.
The superplumes appearing at intervals of 120, 250 myr and, possibly, about 360 and 485 myr are good labels for event synchronization on a global scale. An interval of 120 myr can also be supposed for the Late Precambrian superplumes: at about 610, 730, and 850-860 Ma. Smaller local plumes are expressed between superplumes, with a periodicity of about 30 myr.