Sources and geodynamics of the Late Cenozoic volcanism of Central Mongolia: Evidence from isotope-geochemical studies

Late Mesozoic–Cenozoic intraplate magmatism in Central Asia and its relation with mantle diapirism: Evidence from the South Khangai volcanic region, Mongolia

“…The rocks with the age of 8 Ma have εNd values in the narrow range (from -0.3 to -0.5) at elevated εSr (from 5 to 6). Such isotope compositions are rare among basalts of the Baikal rift and were only reported for few samples collected at the Oka volcanic field [Harris, 1998], Hovsgol [Yarmolyuk et al, 2003] and Central Mongolia [Savatenkov et al, 2010;Yarmolyuk et al, 2015]. Sr-Nd isotopic compositions of the rock of 4 Ma group are in the wider range (εNd from 2.9 to -1.2 and εSr from -1.8 to 5.9).…”

Jom-Bolok Holocene volcanic field in the East Sayan Mts., Siberia, Russia: structure, style of eruptions, magma compositions, and radiocarbon dating

“…Some authors believe that a lower mantle plume is necessary (Yarmolyuk et al 2003b;Savatenkov et al 2010), whereas other authors limit the depths of the source of the magmatism to the mantle transition zone (Zorin et al 2006) or shallower mantle (Barry et al 2007;Rasskazov et al 1997Rasskazov et al , 2002. Two seismic tomography experiments were conducted in Central Asia (e.g., Gao et al 1994;Barruol et al 2008), but they were of insufficient resolution to detect plumes if such exist at depths below the mantle transition zone.…”

Volcanism in the Baikal rift: 40years of active-versus-passive model discussion

“…What is the origin of the volcanism in Central Asia, in general, and in the Baikal rift, Explanations can be grouped into three broad categories in regards to the depth of the source of the magma: (1) lower mantle plume (Rasskazov, 1993;Yarmolyuk et al, 2003bYarmolyuk et al, , 2007aSavatenkov et al, 2010), (2) plumes/diapirs from the transition zone (Zorin et al, 2003(Zorin et al, , 2006Johnson et al, 2005) and (3) involvement of asthenospheric and/or lithospheric mantle (Rasskazov et al, 1997(Rasskazov et al, , 2003aBarry et al, 2003Barry et al, , 2007Demonterova et al, 2007;Hunt et al, 2012). The first two categories belong to the active model of volcanism, when motion in the mantle is the primary cause of the volcanism and lithospheric extension; whereas the latter category belongs to the passive model, when mantle passively responds to plate motions.…”

“…Rasskazov, 1993;Yarmolyuk et al, 2007a) and geochemistry (e.g. Rasskazov et al, 2002;Yarmolyuk et al, 2003b;Johnson et al, 2005;Savatenkov et al, 2010). We do not discuss the complexity of extensive geochemical data here, but wish to point out that other interpretations of almost the same data exist connecting volcanism with upper mantle processes (e.g.…”

“…The Hanagai is different from volcanic fields of the Baikal rift in that majority of lava compositions are basaltic trachyandesites (Barry et al, 2003;Savatenkov et al, 2010). 2003;Savatenkov et al, 2010;Hunt et al, 2012).…”