Comparative analysis of marine paleogene sections and biota from West Siberia and the Arctic Region

The analysis of the main biospheric events that took place in West Siberia and the Arctic region during the Early Paleogene revealed the paleogeographic and paleobiogeographic unity of marine sedimentation basins and close biogeographic relations between their separate parts. Most biotic and abiotic events of the first half of the Paleogene in the Arctic region and West Siberia were synchronous, unidirectional, and interrelated. Shelf settings, sedimentation breaks, and microfaunal assemblages characteristic of these basins during the Paleogene are compared. The comparative analysis primarily concerned events of the Paleocene-Eocene thermal maximum (PETM) and beds with Azolla (aquatic fern). The formation of the Eocene Azolla Beds in the Arctic region and West Siberia was asynchronous, although it proceeded in line with a common scenario related to the development of a system of estuarine-type currents in a sea basin partly isolated from the World Ocean.     

Higher helicity invariants and solar dynamo

Modern models of nonlinear dynamo saturation in celestial bodies (specifically, on the Sun) are largely based on the consideration of the balance of magnetic helicity. This physical variable has also a topological meaning: it is associated with the linking coefficient of magnetic tubes. In addition to magnetic helicity, magnetohydrodynamics has a number of topological integrals of motion (the so-called higher helicity moments). We have compared these invariants with magnetic helicity properties and concluded that they can hardly serve as nonlinear constraints on dynamo action.     

Classification of Harmonic Functions in the Exterior of a Unit Sphere and Its Application to the Description of the External Magnetic Field of the Earth

Geomagnetism and Aeronomy - The magnetic fields of a subterranean source observed on the Earth’s surface or from the orbit of a satellite are studied. We analyze the space of all harmonic...     

Rare earth elements in the peats of Moscow and Tver oblasts

Noticeable amounts of rare-earth elements were first detected in the peats of the earlier drained bogs of Moscow and Tver oblasts. The analysis was carried out by inductively coupled plasma mass spectrometry on an ELAN DRC II instrument (PerkinElmer, United States). The contents of REEs in peat ash of certain deposits are higher than their average contents in the basic rocks and vary in the range of 0.5–60 and 0.1–41.3 mg/kg for the cerium and yttrium groups, respectively.     

Stratigraphy of the Maikop Group and Pteropoda Beds in northern Azerbaijan

Deepwater sections of the Maikop Group (Oligocene-lower Miocene) and overlying lower-middle Miocene sediments are studied near the Perekishkyul Settlement in lower reaches of the Sumgait River, northern Azerbaijan. Several lithological reference levels and the Spiratella (Pteropoda) Beds are used to correlate preliminarily these uniform clayey sections barren of benthic fossils. Based on distribution of the organicwalled and calcareous phytoplankton, spores, pollen and ichthyofossils, the sections are first subdivided in detail and dated. Distinguished in the sections are two regional levels characterizing distortions in the basin hydrological regime during the late Oligocene (level with large Leiosphaeridia and Pterospermella) and Burdigalian (level with dominant dinocysts of the genus Batiacasphaera), and separate intervals with diverse phytoplankton and ichthyofossils. The Tarkhanian sediments are marked by first-appearing oceanic nannoplankton with Sphenolithus heteromorphus and deepwater ichthyofauna with Vinciquerria merklini. The Karaganian is established at the first occurrence level of peculiar endemics (Sardinella karaganica W. Dan. and Mugil karaganicus Swich.) among ichthyofauna.     

Extension of sea surface temperature unpredictability

Ocean Dynamics - The sea surface temperature (SST) variability is clearly affected by global climate patterns, which involve large-scale ocean-atmosphere fluctuations similar to the El...     

Methods of the Theory of Water Flow in Porous Media in Problems Arising in Bog Watering

The analysis of hydrogeological problems arising in bog watering by methods enabling the depth to groundwater table to be controlled was used to develop a method for estimating the efficiency of such control when data for directly solving groundwater flow problems are lacking. The effect of nonmonotone dependence of the rate of groundwater level rise on the hydraulic conductivity of peat underlain by high-permeability sand rocks is described. This effect is shown to be significant in assessing the potentialities of the operational control of groundwater level in bog massifs with this type of geological structure.     

Determination of the Orientation of an Artificial Satellite from Magnetic Field Data in Orbit

Geomagnetism and Aeronomy - At present, the determination of the position of satellite axes from data obtained via measurement of the magnetic field in orbit is an urgent task. This task is...     

Organic-walled phytoplankton from Paleogene sections of Kamchatka

Organic-walled phytoplankton assemblages from Eocene and Oligocene reference sections of western Kamchatka are analyzed. They are close in taxonomic composition to coeval assemblages of northern Japan and Sakhalin that is a good opportunity to correlate regional units and verify their age. The euryhaline species Trinovantedinium boreale that is associated with Paralecaniella indentata and Micrhystridium preferring shallow low-salinity waters, on the one hand, and taxa dwelling in normal-salinity open sea environments, on the other, are dominant in most assemblages, which are examined. The suggested variant of bed succession with dinocyst assemblages may be valid for Japan, Sakhalin, Kamchatka, and the Bering Sea.