The upper Bajocian of the Crimean Mountains: Paleogeography and sedimentation conditions from palynological data

Based on the spore-pollen data, the mineral composition of clay rocks, analyzed structures and facies, and a general paleogeographic analysis, the sedimentation conditions and landscapes of islands located during the Late Bajocian in the region of the present-day the Crimean Mountains have been reconstructed. It is shown that the sublatitudinally elongated insular land zone had a width of 30 km, the heights of the islands were no more than 1 km, with steep mudflow-affected northern slopes and with an extensive river system on the southern slopes.     

Geochemistry of dispersed sedimentary matter and its fluxes in the water column of the Caspian Sea

The first data on the chemical composition of dispersed matter from sedimentary traps are reported. The suspended components of sedimentary matter (amorphous silica, organic matter, carbonates, and lithogenic material, as well as Fe, Mn, and minor elements) are considered. As a result, it is shown that the intraannual variability in vertical fluxes of sedimentary matter is characterized by a seasonal increase in spring and autumn. The high fluxes of the components of sedimentary matter on the northern and southern slopes of the Derbent Basin in winter are explained by precipitation of material from the nepheloid layer that forms over the contour current.     

Modeling meso- and sub-mesoscale circulation along the eastern Crimean coast using numerical calculations

A numerical experiment has been carried out using a hydrodynamical model with nonlinear equations of motion and heat and salt advection to reconstruct the fields of hydrophysical parameters taking into account the real atmospheric forcing for the autumn season along the southern coast of the Crimean Peninsula. The studied part of the coast is situated at 44.25°N 33.95°E/44.72°N 34.55°E. High spatial resolution is used for modeling: 350 m in the horizontal plane with 38 layers in the vertical; the bottom topography is described in detail with ~500 m resolution. Detected and studied meso- and sub-mesoscale structures in the current field agree well with the observational data, which is impossible or hard to identify in numerical experiments with coarser resolution. Their kinematic characteristics and the lifetime are defined and some mechanisms of their origin are suggested.     

Ionospheric response to a rocket launch from the Vostochnyi Cosmodrome

The atmospheric disturbances caused by the first rocket launch from the Vostochnyi Cosmodrome on April 28, 2016, were registered 10–24 min after the launch using the signals of the GPS/GLONASS global navigation satellite systems. The analysis of the spatial distribution of the disturbances allowed the conclusion that the launch vehicle moved northwest from the cosmodrome, which corresponds to a trajectory of the satellite movement to the orbit with an inclination of 98º.     

The Nature and Age of Plagioclasites in the Ultrabasic Rai-Iz Massif (Polar Urals)

Corundum-containing and corundum-free plagioclasites localized in chromite-bearing ultramafites of the Rai-Iz Massif were explored for the composition and age. The composition of rock-forming minerals was studied, and the geochemical characteristics of the rocks were ascertained. The isotope age of plagioclasites determined by zircons using the U–Pb mode with a SHRIMP II device was equal to 398 ± 3 Ma. The age found conformed to the boundary on most of the Rai-Iz Massif took place against the background of a starting powerful collision, which caused the formation of the chromium mineralization of a high-chromic type, as well as the separation of a series of essentially plagioclase rocks of ruby mineralization at the discharge zones of the vein series.     

Determining ammonia nitrogen decay rate of Malaysian river water in a laboratory flume

There is lack of information regarding ammonia nitrogen (AN), (i.e. NH₃-N) decay rate of river water in tropical regions like Malaysia. AN decay rate is a very important kinetic parameter to estimate NH₃-N, nitrate nitrogen (NO₃-N) and dissolved oxygen concentrations of river water by using computer models. This study presents determination of ammonia nitrogen decay rate of river water in the tropical environment of Malaysia. A laboratory flume was used to conduct twelve experiments. The flume was used to represent the turbulent condition of a typical river. Ammonia nitrogen decay rate for the tropical environment of Malaysia was observed to be between 0.194 and 0.554 per day. Median value of AN decay rate was 0.26 per day, which is slightly lower than the global median value of 0.295 per day. To check the accuracy of flume experiments, the AN decay rate of Pusu River obtained from the flume experiment was used to calibrate and validate ammonia nitrogen concentration of the river by using water quality analysis and simulation program (WASP). Very good calibration and validation results were achieved, which substantiated the accuracy of the flume experiments.     

Confusion Noise Sources in the Infrared Wavelength Range

Astronomy Reports - Within the framework of the model of the extragalactic background created earlier by the authors, the factors influencing the statistical properties of the confusion noise have...