pdf № 299, November

DOI: 10.19110/2221-1381-2019-11-3-8

Based on data of the uplift amplitude, obtained from the study of bottom sediments of isolated basins of northeastern Fennoscandia, new schemes of isobases of the uplift were constructed. The uplift was estimated for the past 10,000 years. Interpolation (Triangulation with Linear Interpolation, Natural Neighbor, Local Polinomial) and geostatistical (kriging) methods were used to construct the schemes if isobases of the uplift. It was determined that the most acceptable results of modeling the isobases of uplift, based on a given amount of data, were obtained using the methods Natural Neighbor and Kriging with linear drift. The schemes show the domed character of the uplift of the earth's surface. The maximum amplitude of the uplift (more than 120 meters) is noted in the southwest of the study area.

Keywords: Holocene, glacioisostasia, uplift schemes, interpolation and geostatistical modeling, northeastern Fennoscandia.

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DOI: 10.19110/2221-1381-2019-11-9-19

The Upper Kellwasser Event is recognized for the first time in the deep-water succession of the Kozhym River section on the Western slope of the Subpolar Urals, based on conodont biostratigraphy, lithological changes and positive shifts of the carbon isotope value (d¹³C) across the Frasnian-Famennian (F-F) boundary interval. Conodonts are abundant in the Frasnian Upper rhenana Subzone, but show a low diversity at the level of transgressive Upper Kellwasser Event in the linguiformis Zone, and are almost absent in the Famennian subperlobata Zone. Black shale horizons associated with the global Upper Kellwasser Event were identified in the linguiformis Zone in the Kozhym River section. Positive shifts in the carbon isotope ratio during the linguiformis Zone to the Lower triangularis Subzone (lower part) are observed, similar to those reported from elsewhere around the world (positive d¹³C_carb shifts ~ from 3 to 4 ‰). The data obtained allow the black shales associated with the Upper Kellwasser Event and carbon isotope fluctuations to be precisely dated and correlated.

Keywords: conodonts, Upper Kellwasser Event, Frasnian-Famennian boundary, Subpolar Urals, Kozhym River section.

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DOI: 10.19110/2221-1381-2019-11-20-24

In recent years much new data have been obtained regarding the earliest trees, and their ecology in early forest ecosystems. Aspects of this new data are summarised below, concentrating on the Mid Devonian and earliest Late Devonian, c. 390—380 million years ago, before the dominance of Archaeopteris. The arborescent cladoxylopsids, archaeopteridaleans and lycopsids are considered, as well as the recumbent but large woody aneurophytes. Until now, cladoxylopsid dominated forests, cladoxylopsid/aneurophyte forests, early Archaeopteris, and lycopsid forests are the four forest types identified, largely on the basis of near coastal, wet environments. True in situ fossil forests are extremely rare during this time interval. Future research aims to identify further forest types, to better understand their relationship to palaeogeography and sedimentary environment, and to spread the understanding of early forests beyond the Old Red continent.

Keywords: palaeobotany, forest ecology, Lycopsida, Aneurophytales, Archaeopteridales, Cladoxylopsida.

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DOI: 10.19110/2221-1381-2019-11-25-31

The article is dedicated to the 110^th anniversary of the birth of the outstanding mineralogist of the 20^th century Professor D. P. Grigoriev. Documents relating to the history of the creation of International Mineralogical Association (1958) and the Commission on Cosmic Mineralogy (1962) are published from his personal archive.

Keywords: D. P. Grigoriev, International Mineralogical Association, Commission on Cosmic Mineralogy.

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