编号 7 (2021)

The 14-month sea level oscillations (P14) in the World Ocean, known as the “pole tide”, are assumed to be caused by the “Chandler Wobble”, which are free nutation oscillations in Earth’s axis of rotation with approximately the same period. The maximum amplitudes of these oscillations, observed in the North and Baltic seas, are up to 5–6.5 cm, which are 6–8 times greater than the theoretical values of the pole tide. To examine the nature of this phenomenon, we used longterm (>80 years) data from approximately 100 tide gauges in the two seas. We found that the regional amplification of the 14-month oscillations has a meteorological origin and are associated with corresponding variations in the zonal wind, rather than with the polar motions. Enhancement of the P14 oscillations in the easternmost sectors of the Baltic Sea (in the gulfs of Finland and Bothnia) and in the southeastern sector of the North Sea appear to be related to the shallowness of these regions and to the general tendency for sea level to increase from the “entrance” to the basin’s “head”.

At the maximum of the last glaciation, the shelf of the Laptev Sea was drained, and the coast retreated hundreds of kilometers to the north. With the onset of warming, the sea level began to rise rapidly, flooding the coastal plain. To date, the course of the postglacial sea-level rise has already been gradually reconstructed. We know when the flooding began, how and at what speed the sea rised, where the bulk of the sediments accumulated, and when the transgression stopped. But what was happening in the water column at that time? What water masses prevailed on the shelf, how did the river mouths move southward, what were the temperature and salinity of the surface waters? Has North Atlantic water got to the shelf? Microscopic planktonic organisms that lived at that time and were buried in the bottom sediments of the shelf can tell us about this. Our results of studies of the microalgae complexes in four sediment cores from the shelf and continental slope help to reconstruct the environmental history of the Laptev Sea for the last 17.5 cal. ka.

The data on the first findings of microconchids and cornulitids on the shells of atrypids of Transcaucasia in the range from the Emsian to the Frasnian stage are presented. Epibionts, represented by smooth tubes of the genera Palaeconchus and Cornulites, were found in approximately equal proportions on both the ventral and dorsal flaps of brachiopods. It seems, that the attachment of the studied representatives of the genera Palaeconchus was most likely postmortem, as there is no regularity in their locations. The garlanded nature of the growth of Cornulites, when the constituent members of the garland are approximately of the same size, and the chains of tubes are mouth-directed to the anterior commissure and are located in parallel to the frontal edge, indicates the intravital attachment of these epibionts. During the Devonian period, epibionts were common, though quite rare, elements of the benthic fauna in Transcaucasia. They are characterized by a low level of taxonomic divergence, morphological diversity of adaptive adaptations, and ecological differentiation, which generally indicate the stability of abiotic and biotic environmental conditions.

We publish the transcribed letters written in 1920–1924 from Yekaterinburg by A.V.Shubnikov and his wife O.M.Lebedeva-Shubnikova to Academician A.E.Fersman as well as some comments of these letters. They discuss creation of the Department of Crystallography at the Institute Mines in Yekaterinburg (now, Ural State Mining University), crystallographic research, the organization of scientific work, and difficult life of scientists during the reconstruction of our country after the collapse of the Civil War.

30 ЛЕТ ПРОГРАММЕ «БАЙКАЛ-БУРЕНИЕ» / Отв. ред. М.И.Кузьмин, Е.В.Безрукова. Новосибирск: Академическое издательство «Гео», 2020. 371 с. Ю.А.Золотов. ОЧЕРКИ РОССИЙСКОЙ ХИМИИ. М.: Наука, 2021. 156 с. А.М.Черных, А.А.Аносов. МЕТОДЫ ИССЛЕДОВАНИЯ МОЛЕКУЛЯРНЫХ СТРУКТУР БИОЛОГИЧЕСКИХ ОБЪЕКТОВ. М.: Наука, 2021. 175 с.