Today, metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) are distinguished. Adipose and muscle tissues can determine the obese phenotype due to adipokine and myokine production. Gut microbial community is also involved in MHO. The study was aimed to reveal the features of adipokine and myokine levels and their association with the gut microbiome alpha diversity in patients with MHO and MUO. A total of 265 subjects were divided into two groups: healthy individuals and obese patients. The latter were divided into two subgroups: patients with MHO and patients with MUO. Body mass index, waist circumference, HOMA-IR, adipokine and myokine levels, gut microbiome taxonomic composition, alpha diversity indices were defined in all the surveyed individuals, lipid and carbohydrate metabolism was also assessed. Significant differences in the adipokine and myokine levels and their association with the gut microbiome diversity indicators were revealed in patients with different obese phenotypes. Patients with MHO and MUO showed significantly lower adiponectin levels (р < 0.05) and significantly higher leptin and asprosin levels (р < 0.05) than healthy individuals. Patients with MUO had lower adiponectin and leptin levels (p < 0.05) than patients with MHO. Significantly higher FGF21 levels were observed in patients with MUO. Large-scale correlation analysis revealed the relationship between the glucose levels and the gut microbiome diversity indices that was missing in patients with MUO. This indicated the loss of the microbiota diversity effects on the blood glucose control in individuals with MUO, as well as different regulatory roles in the gut microbiome‒liver‒muscle/adipose tissue axes of individuals with MHO and MUO played by gut microbiota. The findings show the relationship between the gut microbiome diversity and the obese phenotype.

The study is focused on metapelitic granulites of Cape Kaltygei (Western Baikal region) that contain a diagnostic mineral assemblage of ultrahigh temperature (UHT) metamorphic rocks (orthopyroxene+sillimanite+quartz). The pseudosection-based thermobarometry yields peak metamorphic temperature and pressure values (T=950 °C, P=~9 kbar) and suggests near-isobaric cooling (IBC) conditions during the retrograde evolution of the granulites. The U/Pb zircon age estimates for metamorphism (~1.87 Ga) support the data published by other researchers. The SHRIMP-II U-Pb dating of zircon cores yields a minimum protolith age of 1.94–1.91 Ga. Biotites and amphiboles from granulites of Cape Kaltygei show the 40 Ar/ 39 Ar isotopic ages that are close to the Early Paleozoic accretion-collision system of the Western Baikal region.

The western Baikal region (Ol’khon region, Nutgei zone, Kharikta area) is characterized by the development of packets of thrust-type folds and synkinematic granites corresponding to the stage of thrust deformations (overthrust-type granites). Two stages in the formation of thrust-type folds separated by episodes of granite emplacement are definable. The data obtained make it possible to estimate both the time of transition from thrust to strike-slip deformations and the duration of accretionary‒collisional events that resulted in regional strike-slip deformations, which terminated in the western Baikal region 460‒455 Ma ago.

In the Chernorud granulite zone in the Olkhon region of West Pribaikalie, we studied gabbro‐pyroxenites composing tectonic plates (Chernorud, Tonta) and synmetamorphic intrusive bodies (Ulan‐Khargana), as well as nu‐ merous disintegrated boudins and inclusions embedded in the metamorphic matrix. Based on the results of compara‐ tive analysis of the chemical compositions, the gabbro‐pyroxenites are classified into a single island‐arc tholeiitic se‐ ries. The COMAGMAT software was used to simulate this series and to estimate the initial composition of the parent magma (magnesian basalt: SiO2=46.0 wt. %, TiO2=0.8 wt. %, Al2O3=15.3 wt. %, ΣFeO=9.0 wt. %, MnO=0.15 wt. %, MgO=10.5 wt. %, CaO=17.0 wt. %, Na2O=1.0 wt. %, K2O=0.2 wt. %, P2O5=0.05 wt. %, total = 100.0 %, Mg# = 67.5 %). It is concluded that the granulite metamorphism (P=7.7 to 8.6 kbar, T=770 to 820 °C) was due not only to dipping of the initial sedimentary‐volcanic series to a depth of 25–28 km, but also to the presence of a deep chamber of magnesian basalt magma. In our estimations, garnet‐pyroxenites (i.e. mafic rocks of the top facies in the above‐mentioned cham‐ ber) originated at P=8.0–8.3 kbar and T=900–930 °C. Considering petrology, the deep mafic chamber under the layer of granulite facies is evidenced by metamorphic magma mingling, as well as pipe‐shaped intrusions characterized by the specific morphology, internal structure and bulk rock compositions. Based on the data on the Ulan‐Khargana mas‐ sif and gabbro‐pyroxenite bodies involved in the structure of the marble melange, we propose a petrological model showing two stages of mafic injection – Stage 1: hydraulic fracturing of granulite series and the emergence of tubular structures and bodies, which are similar to kimberlite pipes or channels of different shapes; Stage 2: rising of the flu‐ idized residual alkaline melt through the emerging ‘pipes’ and fractures armored by hardened zones, which is fol‐ lowed by metamorphic magma mingling under viscous deformation conditions. The mafic magmas intruding to the level of the granulite facies facilitated the deep anatexis and formation of synmetamorphic hypersthene plagiogranites (U‐Pb isotope dating: 500–490 Ma) and high‐K stress granites. In the Chernorud granulite zone, intense ductile‐plastic and brittle‐plastic deformations accompanied the processes of metamorphism, intrusion and formation of gabbro‐ pyroxenites and the anatexis of the crustal substance. As a result, the intrusive bodies were fragmented, and specific tectonic structures termed ‘metamorphic magma‐mingling’ were formed. All the tectonic and magmatic structures were subsequently ‘sealed up’ by K‐Na synkinematic granites at the regressive stage under conditions of the amphibo‐ lite‐facies metamorphism (U‐Pb and Ar‐Ar isotope dating: 470–460 Ma).

Geochemical study of the metamorphosed pillow lavas of the Chara Zone revealed that their protoliths have N-MORB compositions. Elevated concentrations of K, Rb, Cs, and lower Ca may be related not to blueschist metamorphism, but rather they may be inherited from underwater alteration of parental basalts. Comparative analysis of the compositions of massive glaucophanites and vein rocks demonstrated the relative mobility of Sr, U, P, Ba, Rb, K, Cs, Ca, and LREEs, at least on the local scale. Their mobility has been provided by fluids circulating in the subduction zone, where the fluids have been generated through slab dehydratation processes. These studies of metamorphosed pillow lavas of the Chara Zone displayed only local alterations in the bulk composition of their protoliths, which evidences a low intensity of fluid flows: this allowed preservation of the geochemistry of oceanic basalts.

Ion microprobe data for minerals from the eclogites of the Atbashi Range (South Tianshan) constrain the distribution of trace (Rb, Sr, Ba, Cr, V, Zr, Hf, Nb, Ta, U, Th, and Y) and rare-earth elements (REE) in zoned garnets and mineral inclusions in them. This study showed that garnets from the Atbashi eclogites are the main hosts for heavy REE; epidotes are important hosts for REE, Y, Sr, Th, and U; and omphacites are depleted in almost all trace elements compared with the bulk-rock compositions. Garnet, as well as epidote and omphacite inclusions exhibit systematic rimward depletion in a number of trace elements, which is related to the depletion of the rock matrix in these elements during crystallization. Deviations from this trend, including the enrichment of garnet rims in HREE and strong variations in the REE contents of garnets and mineral inclusions, can be explained by metamorphic reactions involving the destabilization of REE-bearing minerals. Our data suggest that the mobility of trace elements under eclogites-facies conditions is mainly controlled by the stability of certain minerals.

В работе приведены данные геохимических и Sm-Nd изотопных исследований метаморфических комплексов Горного Алтая, дополненные синтезом результатов полученных ранее геологических и геохронологических данных.Показано, что все проявления высокометаморфизованных пород приурочены к блокам, ограниченным крупными разломными зонами и не имеют постепенных переходов к неметаморфизованным толщам обрамления. Какие-либо надежные геологические или изотопно-геохронологические доказательства раннедокембрийского возраста метаморфических событий в Горном Алтае отсутствуют. Геохимические характеристики метаморфических пород Горного Алтая свидетельствуют о “незрелой” природе их протолитов. Метапелиты по вещественному составу отвечают продуктам коры “переходного” типа, метабазиты соответствуют либо океаническим (от N-MORB до OIB), либо толеитовым и известково-щелочным базальтам примитивных островных дуг. Пород, сформированных за счет метаморфизма “зрелых” коровых протолитов в ходе проведенных исследований не обнаружено. Модельный возраст метаморфических пород Горного Алтая колеблется в интервале от 0.8 до 1.6 млрд. лет и не превышает такового для раннепалеозойских осадочных толщ региона. Вся совокупность полученных данных позволяет утверждать, что комплексы метаморфических пород Горного Алтая представляют собой фрагменты неопротерозойской – раннепалеозойской коры, метаморфизованные в ходе более молодых геологических событий. В целом же допозднерифейский кристаллический фундамент в Горном Алтае отсутствует, а сам Горно-Алтайский сегмент Центрально-Азиатского складчатого пояса сформирован на океаническом основании.

New data on the spreading and geochemical features of lithium-bearing underground waters in the Irkutsk Region and Western Yakutia are presented. A taxonomic partitioning of the hydrogeological section of the Siberian Platform was carried out, and promising salt-bearing zones were allocated.

Intrusions of the Irtysh Complex are spatially restricted to the regional Irtysh Shear Zone (ISZ) and are hosted in blocks of high-grade metamorphic rocks (Kurchum, Predgornenskii, Sogra, and others) in the greenschist matrix of the ISZ. The massifs consist of contrasting rock series from gabbro to plagiogranite and granite at strongly subordinate amounts of diorite and the practical absence of rocks of intermediate composition (tonalite and granodiorite). The complex was produced in the Early Carboniferous, simultaneously with the onset of the origin of the ISZ itself. The granitoids composing the complex affiliate with diverse petrochemical series (from subaluminous plagiogranite of the andesite series to granite of the calc-alkaline series) and contain similar REE and HFSE concentrations [total REE = 103–163 ppm (La/Yb) n = 3.59–5.44, Zr (200–273 ppm), Nb (7.6–10.6 ppm), Hf (6.1–7.6 ppm), and Ta (0.68–1.19 ppm)] but are different in concentrations in LILE [Rb (3–9 and 121–221 ppm), Sr (213–375 and 77–148 ppm), and Ba (67–140 and 240–369 ppm)] and isotopic composition of Nd (ɛNd(T) from +5.3 in the plagiogranite to −1.2 in the granite) and O (δ18O from +9.4 in the plagiogranite to +14.5 in the granite). Data on the geochemistry and isotopic composition of metamorphic rocks of the Kurchum block and numerical geochemical simulations indicate that the granitoids were generated via the melting of a heterogeneous crustal source, which consisted of upper crustal metapelites and metabasites of the oceanic basement of the blocks of high-grade metamorphic rocks. The differences in the chemical and isotopic compositions of the granitoids were predetermined by the mixing of variable proportions of granitoid magmas derived from metapelite and metabasite sources.

A brief review of Ordovician blueschist complexes on the southwestern framing of the Siberian craton is presented in order to place further age constraints on the tectonic evolution of the Central Asian orogenic belt (CAOB). Three different blueschist localities (imbricated slices of blueschists in the Uimon Zone, Gorny Altai; a blueschist unit in the Kurtushiba ophiolite belt; blocks of blueschists and eclogites in a serpentinite mélange of the Chara (Char) zone, northeastern Kazakhstan) are considered. We obtained 40Ar/39Ar dates for white micas and sodic amphiboles from blueschists of the Uimon Zone (490–485 Ma), Kurtushiba belt (470–465 Ma), and Chara zone (450 Ma), suggesting the Ordovician ages of the subduction/exhumation of these complexes. The dates obtained also coincide with the metamorphic ages of many blueschist belts in North China, which allows us to distinguish the Ordovician stage of accretion-collision events in the tectonic evolution of the CAOB.