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The Early Devonian Altai-Sayan rift system (ASRS) has spread to the structures of East and West Sayan, Kuznetsk Alatau, and Mongolian Altay. Its largest fragments are the Tuva, Delyun-Yustyd, Kan, Agul, and Minusa basins as well as depressions in northwestern Mongolia. The paper summarizes the geologic, geochemical, and Sr-Nd isotope characteristics of the ASRS mafic rocks represented by nappes of moderately alkaline and alkali basalts and their subvolcanic and intrusive rock analogues. They are present in all magmatic associations and are divided into low-Ti (TiO₂ = 0.2-2.2 wt.%) and high-Ti (TiO₂ = 2.2-4.3 wt.%) subgroups. These rocks are characterized by wide variations in Sr isotope characteristics (ε_Sr(T) = -16 to +30). High-Ti mafic rocks are common at the southern segment of the ASRS; they show a weak positive Ta-Nb anomaly (La/Nb = 0.8-1.1) and are relatively enriched in LREE ((La/Yb)_N = 6-14) and radiogenic Nd (ε_Nd(T) = 3.8-8.7). Low-Ti varieties are confined to the northwestern segment of the ASRS; they are enriched in Ba but depleted in Th, U, Nb, Ta (La/Nb = 1.2-2.2), Zr, Hf, LREE ((La/Yb)_N = 3-7), and radiogenic Nd (ε_Nd(T) = 2.0-6.0). Taking into account the existence of different terranes, which were combined in the structure of the Altai-Sayan folded area during accretion (ca. 500-480 Ma), we propose a model suggesting different environments of magma formation at the southern and northwestern segments of the ASRS and the relationship of magmatism with a mantle plume within the ASRS. In composition the plume corresponds to the sources of high-Ti magmas. The effect of the melted lithospheric mantle of different compositions beneath different groups of terranes led to the observed isotope-geochemical heterogeneity of mafic rocks within the ASRS, in particular, the absence of high-Ti mafic rocks from the Minusa basin.

Rock samples from the Khamaryn-Khural-Khiid combustion metamorphic (CM) complex, including cristobalite clinker, ferroan tridymite-sekaninaite and cristobalite-fayalite paralavas, which are rock types new to the complex, as well as clinker xenoliths in melilite-nepheline paralava, have been studied in terms of chemistry and mineralogy. The obtained data on rock-forming, minor, accessory, and rare phases (silica polymorphs, cordierite-group minerals, fayalite, Fe and Ti oxides, ferrosilite, etc.) have implications for the formation conditions and processes of the CM rocks. The Raman spectra of sekaninaite, indialite, ferroindialite, mullite, and anhydrous Fe-Ca-Mn phosphate, presumably from the graftonite group, have several specific features. The diversity of mineral assemblages in the CM rocks is due to heterogeneous lithology of the sedimentary protolith and to local effects in the multistage history of the Khamaryn-Khural-Khiid complex. According to geochemical data, all CM rocks of the complex are derived from the Early Cretaceous Dzunbain Formation, their protolith molten to different degrees. The cristobalite clinker and tridymite-sekaninaite and cristobalite-fayalite paralavas were produced by partial melting of pelitic rocks containing different amounts of iron in a wide temperature range. The formation of mullite developed from dehydration-dehydroxylation and incongruent partial melting of amorphous pelitic matter. Large-scale crystallization of mullite in clinker, occurred from the high-silica potassic aluminosilicate melt at >850 °C. Combustion of subsurface coal seams heated the overburden to >1050 °C or locally to >1300-1400 °C (melting point of detrital quartz) or even, possibly, to >1470 °C corresponding to the stability field of β-cristobalite. Melilite-nepheline paralava was formed by incongruent melting of silicate (pelitic) and carbonate (calcite) components of marly limestone under elevated CO₂ partial pressure. Oxygen fugacity ( ƒ _O2) during combustion metamorphism changed from strongly reducing conditions favorable for crystallization of Fe phosphides (barringerite, schreibersite) and metallic iron from silica-undersaturated melts parental to melilite-nepheline paralava to high ƒ _O2 values that can maintain the formation of hematite in Fe-rich CM rocks.

The geochemical and mineralogical aspects of the distribution of rare-earth elements (REE) in ferruginous deposits (FD) and bottom sediments of the southeastern Laptev Sea are analyzed. The FD are dominated by biomorphs developed after polychaete tubes. The REE patterns depend on the proportion of ore and non-ore substances. The ore substance is represented mainly by iron hydroxides (limonite). It is a product of suboxic diagenesis enhanced by bioturbation and determines the slight enrichment of FD in MREE and cerium deficiency (Ce_an = 0.94). The non-ore substance comes from terrigenous sediments and has an (alumino)silicate composition. It controls the scandium content and is the source of REE mineral grains, among which monazite-(Ce) prevails. The sediments demonstrate a common similarity in REE patterns to shales and suspended material transported to the Laptev Sea by the Lena River, with elevated LREE and MREE contents and the value of Ce anomaly almost equal to unity (Ce_an = 1.06). In the sediments, REE minerals occur mostly in the silt fraction (<63 μm in size). The high content of organic matter (C_org of up to 2.15%) of predominantly terrigenous origin (OM_ter of up to 85%) in the sediments explains the oxygen deficiency and weak diagenetic mineral formation with low accumulation of trace elements, including REE, in the FD. The total REE content in the FD is lower than that in the sediments (on average, 173 ppm against 206 ppm).

The Bazhenov Formation of the Western Siberian oil-and-gas province is currently one of the key objects of potential growth in oil reserves and production. Here we present results of a geochemical study of the Bazhenov Formation according to the methodology developed at Trofimuk Institute of Petroleum Geology and Geophysics, Novosibirsk (IPGG SB RAS) for rocks highly enriched in organic matter. The features of the group and hydrocarbon compositions of the bitumoids that are filling open and closed pores of the Bazhenov Formation rocks from the North-Surgut region were considered. It has been established that most of the naphthides are in a free (phase-segregated) or sorbed state in a closed pore space. The open pores contain the most mobile components of bitumoids, redistributed from closed pores during the primary migration and remained after the secondary migration of naphtides from the Bazhenov Formation to the Berriasian-lower Aptian reservoirs (A and B strata groups). The methodology used in this work allows determining intervals with increased open porosity and oil saturation in the section of the Bazhenov Formation (silicites and carbonates) by the volume of pore space occupied by open-pore bitumoids.

The Bachat earthquake ( M = 6.1) with the epicenter coordinates of 54.29° N, 86.17° E occurred on June, 18 2013 near the Bachatsky coal strip mine, is the world’s largest earthquake induced while mining solid minerals. More than 5000 aftershocks were registered and the spatial volumetric structure of the aftershock area was investigated. The Bachat coal field is located in the Salair zone of the Kuznetsk Depression and is represented by a brachysynclinal fold of a very complex structure characterized by the damage and fracturing behaviors of rocks. The main event is confined to the coal-mine pit wall, with the greatest density of aftershocks observed in its middle portion. In the cross section, aftershocks form a wide area with its deepened portion shifted towards the Kuznetsk Depression, while large faults bounding the depression dip down under the Salair Ridge. In the exposed pit wall, at a depth of 4 km, the activated area resembles a rhombus whose horizontal diagonal line runs across the entire length of the mine pit and decreases both in upward and downward directions. The area is seismically activated to a depth of 6 km, with more intense activation of rock mass observed within the 1-3 km depth interval. Results of the study of the mechanisms of aftershock sources revealed a disagreement between the stress state of rock mass of the Bachatsky open-pit coal mine modeled from the mechanisms of aftershocks, and the mainshock mechanism of the Bachat earthquake.

The digital elevation model (SRTM03) of the central part of the Lower Amur province is analyzed. The Limuri-Amgun ring structure is identified on the basis of a set of features, and it is also the location of the Pilda-Limuri and Kherpuchin-V’yunsky gold-ore regions, as well as the Albazino deposit, known for large industrial gold deposits and many small deposits and ore occurrences. The distribution of linear and ring elements of the relief is analyzed and geologically interpreted, and its spatial relationship with gold deposits and ore occurrences is shown. The relationship between the morphological severity of the ring structure and the deep structure of the region is shown. It is revealed that the structure is magmatic and characterized by a high concentration of intrusive bodies. According to the reference data on the age and composition of the igneous complexes of the region, the formation of the ring structure is associated with the processes of neoformation and transformation of the Earth’s crust and upper mantle during the end of the Late Cretaceous and the beginning of the Paleocene in a suprasubduction geodynamic setting.

The genetic differentiation of Siberian larch (Larix sibirica Ledeb.) populations in the latitudinal gradient of climatic conditions was studied based on high-throughput double digest restriction-site associated DNA sequencing (ddRADseq) data. We studied the correlation of five main climatic variables with the variability of 47,929 single nucleotide polymorphisms (SNPs). A total of 125 trees were studied: 61 trees in four populations along the western geographic transect and 64 trees in four populations along the eastern geographic transect. 21 SNPs with signatures of selection were identified, including 9 outlier SNPs whose variability cannot be explained by selectively neutral processes, and 12 SNPs whose variability correlated with the environmental factors. Seven SNPs are located in the introns of mitochondrial genes, three are located relatively close to the mitochondrial genes encoding NAD2 and ribosomal proteins S7 and S11, one is located at a distance from the nuclear gene encoding a protein homologous to the microtubule-associated futsch-like protein of Arabidopsis thaliana, two in the protein genes of an unknown nature and three in contigs containing no genes, and for which no homologous sequences were found in the NCBI GenBank.

The Siberian spruce (Picea obovata Ledeb.) pollen viability was studied on the border of Krasnoyarsk city as well as unpolluted growth conditions. The study discovered the variability and correlation between the functional characteristics of pollens, as well as a low rate of development anomalies. The viability of pollen growth in forest ecosystems of the Eastern Sayans middle mountains (northeast border of national park “Krasnoyarskie Stolby”) decreased under pollution press. A great variety of pollen viability characteristics of the Siberian spruce pollen makes evident the high degree of flexibility and adaptability of species′ reproductive processes.

The results of cytogenetic analysis of four embryogenic cell lines of Siberian larch (Larix sibirica Ledeb.) of different ages: young (two four-month and 16-month CLs) and long-proliferating (11-year CL) are presented. Three cell lines are diploid and contain in the karyotype the normal number of chromosomes for this species (2n = 24). A 16-month-old CL capable of forming somatic embryos was aneuploid (2n = 25). This cell line is probably characterized by trisomy on one of the pairs of submetacentric chromosomes. The long-term proliferating CL, from which regenerants and clones were obtained, retains a diploid number of chromosomes during 11 years of cultivation and remains genetically stable. The karyotype of conifers is characterized by high degree of stability and most of the species contain 24 chromosomes (2n = 24). Therefore, the detection of cytogenetically stable cell lines is of great interest for genetic work of this group of plants and creation of highly productive plantations with specified hereditary properties.

With the use of six polymorphic microsatellite markers of nuclear DNA in the territory of oil complex of Western Siberia’s activity, a pilot study of three closely spaced populations of Pinus sylvestris L. - bog land, dry land, and "technogenic" (originated on the sandy base of the drilling pad) was carried out. It showed that the studied populations are quite close in terms of the main parameters of genetic variability, assessed by six polymorphic loci. At the same time, small but statistically significant differences were found between the dry land and bog land populations, including one’s in FIS. The "technogenic" population has an intermediate position between the studied natural populations and does not show statistically significant differences from them. It has been suggested that the most likely cause of the latter is the formation of "technogenic" young pine stands from a mixture of genotypes of the dry land and bog land populations, as well as that the appearance of unique (private) alleles in the "technogenic" population and adjacent bog land population can be induced by chemical pollution.