Neoproterozoic evolution of the northwestern margin of the Siberian Platform

Mongolian micro‐continental blocks in Columbia/Nuna: Zircon U–Pb–Hf isotopic evidence for long‐lasting Mongolia–Western Siberia connection

“…Samples PV274 and IS192 additionally record an important Tonian tectono‐metamorphic event; although this event is not recorded in the compilation of zircon Hf data from Western Siberia, we note recent U–Pb zircon studies have documented Tonian zircons in mid‐ to late‐Neoproterozoic strata (e.g. Kochnev et al., 2022), and there is a strong correlation in the Hf zircon data to the Central Taymyr Belt of Northern Siberia (Priyatkina et al., 2017; Figure 5). Nonetheless, this Tonian tectono‐metamorphic event is often presented as diagnostic of a Tarim‐Mongolia connection in the Neoproterozoic (Bold et al., 2016; Rojas‐Agramonte et al., 2011), and our new data and a Mesoproterozoic position proximal to Western Siberia do not exclude this possibility.…”

“…The latter is supported by palaeomagnetic data (Levashova et al., 2010) and previous detrital zircon studies of Neoproterozoic–Palaeozoic strata, which have emphasized the importance of a Tonian tectonic event that is observed in the detrital zircon record of Tarim but only insignificantly in Siberia (Bold et al., 2016; Rojas‐Agramonte et al., 2011). Although this absence in Siberia is somewhat overstated in light of more recent geochronological work (Gillespie et al., 2018; Kochnev et al., 2022; Priyatkina et al., 2018). Herein, we present the first comprehensive detrital zircon geochronology study from Mesoproterozoic strata belonging to the Baidrag Block of the Mongolian Collage; these data shed new insight into this problem by providing constraints on the pre‐Rodinian position of the Monoglian micro‐terranes.…”