Global implication of mesoproterozoic (~ 1.4 Ga) magmatism within the Sette-Daban Range (Southeast Siberia).

Mesoproterozoic period included several global tectonic events like break-up of Nuna and formation of Rodinia. However, although Siberia is a significant piece of both supercontinents, Mesoproterozoic time is marked by quiescence of magmatic and tectonic activity in it. We report here a mafic dyke (named Gornostakh dyke) in the southeastern Siberian Craton dated at 1419 ± 32 Ma by LA-ICPMS U-Pb geochronology of apatite.

Origin of alkali-rich volcanic and alkali-poor intrusive carbonatites from a common parental magma.

The discrepancy between Na-rich compositions of modern carbonatitic lavas (Oldoinyo Lengai volcano) and alkali-poor ancient carbonatites remains a topical problem in petrology. Although both are supposedly considered to originate via fractional crystallization of a "common parent" alkali-bearing Ca-carbonatitic magma, there is a significant compositional gap between the Oldoinyo Lengai carbonatites and all other natural compositions reported (including melt inclusions in carbonatitic minerals). In an attempt to resolve this, we investigate the petrogenesis of Ca-carbonatites from two occurrences (Guli, Northern Siberia and Tagna, Southern Siberia), focusing on mineral textures and alkali-rich multiphase primary inclusions hosted within apatite and magnetite.

Methane release from carbonate rock formations in the Siberian permafrost area during and after the 2020 heat wave.

Anthropogenic global warming may be accelerated by a positive feedback from the mobilization of methane from thawing Arctic permafrost. There are large uncertainties about the size of carbon stocks and the magnitude of possible methane emissions. Methane cannot only be produced from the microbial decay of organic matter within the thawing permafrost soils (microbial methane) but can also come from natural gas (thermogenic methane) trapped under or within the permafrost layer and released when it thaws.

Data on the C date obtained from the charcoal figure "Black fox" in Shulgan-Tash (Kapova) cave, Southern Ural, Russia.

Shulgan-Tash (Kapova) cave in southern Ural, Russia, is the easternmost European site hosting Late Paleolithic cave art. Most of the 195+ drawings catalogued in the cave are made with red natural pigment (ochre), and only a handful of drawings are made with charcoal, see "Catalogue of images" [4], "Höhlenmalerei im Ural: Kapova und Ignatievka; die altsteinzeitlichen Bilderhöhlen im sudlichen Ural," [5]. "Constraining the ages of the Late Palaeolithic cave paintings in the Shulgan-Tash cave, Southern Urals, Russia" [6].

Late Palaeolithic cave art and permafrost in the Southern Ural.

Shulgan-Tash (also known as Kapova) cave located on the western slope of the Ural Mountains (Russia) is the easternmost European cave art monument of late Palaeolithic age. Radiocarbon dates from cultural layers in the cave suggest an age of about 16.3 to 19.

High-temperature mass spectrometric study of the vaporization processes and thermodynamic properties of samples in the Bi O -P O -SiO system.

Rationale: The Bi O -P O -SiO system possesses a number of valuable properties that may be of use for various practical applications, both for obtaining new materials, e.g. optical fibers, and for replacing systems based on toxic lead silicate.