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The study of Triassic paleontology and stratigraphy of various regions of northeastern Russia and adjacent Arctic shelf is essential not only for improving and refining zonal biostratigraphic schemes, interregional and global correlation of Triassic deposits, and resolving problems of stratigraphic boundaries but also for developing and substantiating a new generation of Triassic stratigraphic schemes, which could serve as the stratigraphic basis for different regional and detailed geological investigations of the Arctic. The results of the study were used to improve existing zonal scales based on various groups of fauna and palynomorphs, develop a more detailed biostratigraphic subdivision of the Triassic, and characterize individual horizons using both terrestrial and marine palynomorphs. The zonal scales are calibrated to each other and to the regional zonal scale of the Triassic of Siberia and northeastern Russia, which provides the subsequent correlation with the International Chronostratigraphic Chart of the Triassic System. The set of coeval zonal scales for the Triassic of Kotelny Island sections based on ammonoids, nautiloids, coleoids, bivalves, brachiopods, and foraminifers and the analysis of microphytoplankton and terrestrial palynomorph assemblages are a useful tool for detailed subdivision and correlation of the eastern part of the Laptev Sea shelf and adjacent regions of northeastern Russia.

The research team studied the petrology, whole-rock geochemistry, zircon U-Pb age, and stable isotopic characteristics of the Rongguo Longba and Garongcuo granites of the Nuocang area to understand better the impact of Neo-Tethys ocean subduction and India-Eurasia continental collision on Paleocene tectonomagmatic processes along the southern margin of the Gangdese Belt. The Rongguo Longba granite and Garongcuo granite porphyry formed at 61.86 and 62.17 Ma, respectively. The Nuocang granitoids are characterized by (1) high SiO₂, NaO₂, and Al₂O₃ contents and low FeO_tot, MgO, and TiO₂ contents; (2) LREE and LILE enrichment and HREE and HFSE (Nb, P, and Ti) depletion; and (3) obvious negative Eu anomalies. These features indicate that the Nuocang granites are of the high-K calc-alkaline and peraluminous granite types. Furthermore, their zircon Hf isotope characteristics suggest that the magma source region has an ancient crystalline basement. The basaltic andesitic crystal tuff is the product of garnet-peridotite partial melting and crust contamination from rising magma emplacement.

The Sichuan Basin is a typical intracraton superimposed basin. It is rich in oil and gas resources in the different sets of sedimentary sequences. It underwent multistage tectonic evolution, which resulted in different types of prototype basins. However, there are still many different opinions on the types and superimposed patterns of the Sichuan Basin in different geologic periods, which largely affect the understanding of the mechanism of effective oil and gas accumulation and preservation. This paper aims to re-recognize several prototype types of the Sichuan Basin by discussing the prototype basins and their superimposed models to deepen the significance of superimposed basin evolution for hydrocarbon accumulation. The regional geological and drilling data are used for a detailed interpretation of seismic reflection profiles across Lushan-Chishui. Then, five regional unconformities are identified with the equilibrium profiles technique, which is used to flatten the formation interface in different geologic periods. Based on the unconformities, the southern Sichuan Basin is divided into six tectonic layers, each of which is regarded as a prototype basin: a pre-Sinian crystalline basement (AnZ), a marine rift cratonic basin (Z-S), a marine intracratonic sag basin (P₂l-T₂l), a marine-continental downfaulted basin (T₃x¹-T₃x³), a continental depressed basin (T₃x⁴-J), and a foreland basin (K-Q). The different prototype basins are vertically superimposed to form a “layered block” geologic structure of the multicycle basins. Affected by the late-stage tectonic transformation, the geologic structure of vertical stratification underwent a strong transformation, which had a profound impact on oil and gas accumulation with the characteristics of early accumulation and late adjustment.

In the northern Tarim Basin, a large number of thick igneous rocks are encountered in the drilling process in the Permian. Their lithology and velocity are very strongly, which has a great influence on migration imaging of the “beaded” areas. It is very important to conduct the fine lithology identification and high-precision velocity modeling of the igneous rocks for the exploration and development of the reservoirs. A geostatistical inversion method to obtain the igneous-rock lithologic distribution pattern and velocity modeling in the FY area of the northern Tarim Basin is introduced in this paper. The results show that the application of the geostatistical inversion method greatly improves the resolution of lithology identification. This helps us further understand the Permian igneous rocks distribution in the FY area. Comparison between the seismic facies classification maps of the FY study area shows that the obtained velocity model can reflect the lateral distribution of igneous rocks well. At the same time, the velocity model can reflect the variation of igneous rocks velocity in detail and has a high precision. The average velocity error of the wells participating in the inversion is less than 2%, and the minimum average velocity error is 0.23%. Finally, the velocity model is applied to seismic data processing, and the processing results indicate that it can help to improve seismic migration imaging. The study demonstrates that the geostatistical inversion method can provide a high-precision velocity model for formation pressure prediction and seismic data processing and interpretation, ultimately guiding the exploration and development of oil.

The hydrocarbon formation mechanism and potential targets in clastic strata from the Tabei Uplift, Tarim Basin, are documented using the fault mesh petroleum plays theory, based on integrating seismic, well log, well core and geochemistry data. The reservoirs in the Donghetang area are typical allochthonous and far source fault mesh petroleum plays. There are two sets of fault meshes in the study area: (1) the Donghe sandstone and combination of Permian and Triassic strata and (2) combination of the J_IV and J_III formations in the Jurassic strata. The fault mesh petroleum play in the Jurassic is a secondary reservoir that originates from the Carboniferous Donghe sandstone reservoir adjustment based on source correlation. The fault mesh carrier systems are divided into four styles according to the fault mesh architecture: (1) fully connected, (2) fault-unconformity-transient storage relay, (3) fault-transient storage-unconformity relay, and (4) transient storage-fault relay. According to the characteristics of the fault mesh petroleum plays, the reservoirs are of 15 types and form three categories: upper transient storage, inner transient storage, and margin-transient storage. Integrated analysis of the hydrocarbon generation and faulting time periods reveals that there were four periods of hydrocarbon charging, with the first three stages charging the reservoirs with oil and the last stage charging the reservoirs with gas. There are multiple stages of reservoir accumulation and adjustment in the fault mesh in the study area. These multiple stages of fault mesh accumulation and adjustment are the main reason that the multiple vertical units of the reservoirs have different hydrocarbon properties. Fault-block reservoirs and lithologic reservoirs related to the inner transient storage and upper transient storage styles are the main exploration targets in the clastic strata in the study area.

The Lahroud Ophiolite in northwestern Iran contains extensive zones of Paleozoic ophiolite as remnantsof the Paleo-Tethys oceanic crust. The principal rock units are gabbro overlain by pillowbasalt, which is intruded by granites and interbedded with pelagic sedimentary units including radiolariancherts. Geochemistry and radioisotope studies, supported by Nd, Sm, Sr, and Pb isotope data, indicatethat the Lahroud Ophiolite originates from a within-plate basaltic mantle source. The isotope studiesshow that the basalts are derived from Indian-type oceanic mantle sources. The radiogenic data indicatethe involvement of subduction-related terrigenous materials in the source magma. All the rocks are geochemically cogenetic and were generated by fractionation of a melt with a composition of average E-MORB with a calc-alkaline signature. Two ⁴⁰Ar/³⁹Ar ages, 343 ± 3 Ma for muscovite minerals and 187.7 ± 7.7 Ma for glasses, suggest that metamorphic and basaltic rocks formed during the Late Paleozoic to Early Jurassic, respectively. Microfossil studies show the presence of Paleozoic biostratigraphy. The crystallization process and rifting into the oceanic crust in the Lahroud Ophiolite probably began in the Carboniferous, with volcanic activity continuing during the late Triassic.

The effect of the Reynolds number on the mechanism of formation of an instantaneous local flow separation that occurs in the near-wall region of a turbulent boundary layer is experimentally studied. The features of application of the high-speed planar PIV method with a high spatiotemporal resolution are discussed. Comparison of the measurement results obtained within a viscous sublayer of a turbulent boundary layer with the results of other studies showed the generality of the mechanism for the formation of an instantaneous local flow separation in the range of dynamic Reynolds number 207 ≤ Re _τ ≤ 672.

A three-dimensional turbulent round jet impinging on a heated flat plate is investigated numerically. The effects of the nozzle geometry and nozzle-to-plate distance on the dynamical and thermal behavior are explored. A round nozzle and nozzles fitted with either 4 or 6 chevrons are considered. Three nozzle-to-plate distances are studied: H/D = = 2, 4, and 6. The Reynolds number equals 5000. The results show that the chevrons improve the heat transfer near the area of stagnation. This improvement can reach up to 110 % in specific regions. It is also found that the wall heat flux is appreciably non-uniform for the small distance H/D = 2. Degraded heat transfer is recorded between the plate and the fluid in narrow radial passages of fluid downstream of the stagnation point for the small value of H/D. They turn out to be quasi-potential flow streams, along the target wall and facing the chevron apices, characterized by high convective velocities and nearly no turbulence. Increasing the distance to H/D = 6 yields a somewhat axisymmetric thermal behavior. Effects on Nusselt number values averaged over circular surfaces centered on the stagnation point and of variable radius on the target wall are highlighted.

Mathematical simulation was applied to flame spreading and the flame front speed through the air suspension of boron particles as a function of pressure, excess oxidant ration and the particle size. Simulation accounts for a change in heat and mass transfer with a reduction of the particle size from micro-size to nano-scale. The model of flame front propagation through boron particle suspension in air (with account for molecular-kinetic mechanism of heat and mass transfer) allows analysis of the normal speed of flame propagation as a function of initial size of boron particles, oxidant excess ratio and pressure. The conditions were estimated and existence of extremes and flat zones was justified due to a change in heat and mass transfer regime change in a continuous medium while transition to the free-molecular flow regime.

The experimental results obtained by the dilatometric method for thermal expansion of the Hastelloy C276 alloy in the temperature range of 100 - 370 K are presented. Temperature dependences of thermal properties have been obtained. The obtained results have been compared with the data for thermal expansion of superconducting tapes of the “Amperium” and “SuperOx” brands Keywords: