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1

Stratigraphy and palaeoceanography of late Pleistocene molluscs from the northern coast of the Persian Gulf

Gholamalian Hossein, Hassani Mohammad-Javad, Keshavarz Musa

Geological Quarterly

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2022

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Vol. 66, No. 2

art. no. 17

EN

We report an extraordinary discovery of marine Pleistocene strata from the north of the Persian Gulf. The Dayyer section contains a rich molluscan fauna including 26 bivalve species, Sr87/Sr86 data showing that the succession is not older than 153 ka (late Pleistocene). These strata are time-equivalents of the Bakhtiari Formation, but have a very different fossil content and facies. Comparing the Dayyer molluscan community to the present-day fauna of the Persian Gulf shows that many fossil species are absent in the recent waters. The palaeoceanographic distribution of the identified bivalves shows the presence of many of them in the Plio-Pleistocene strata of the Mediterranean Basin. This may point to a temporary connection between the Persian Gulf and Mediterranean Basin during the late Pleistocene and the extinction of many bivalves in the past 153 ka

2

„Middle Polish fluvial high terrace” in the river valleys of the Kielce - Łagów Depression (Holy Cross Mountains, Poland) – fact or myth?

Ludwikowska-Kędzia Małgorzata

Studia Geomorphologica Carpatho-Balcanica

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2021

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Vol. 55

129--152

EN

The article is a commentary on the current state of knowledge of the formation conditions, origin and stratigraphic position of the „Middle Polish fluvial, fluvioperiglacial high terraces” being relief elements of the river valleys of the Kielce– Łagów Depression (KŁD) in the southern part of the Holy Cross Mountains (HCM), i.e. the Belnianka, Lubrzanka and Łagowica river valleys. The former conception and criteria of distinguishing them are no longer fully valid. The “high terraces” were formed in the studied valleys in periglacial conditions of the Vistulian Glaciation and not, as it was previously considered, during the “Middle Polish Glaciation”. They are entirely or partially composed of slope deposits or formed within the cover of glacial and / or slope deposits (toe-cut terraces) of different ages (including derived from the Odra Glaciation). Their hypsometric position is determined by the features of structural relief and the possibility of deposition of slope sediments on the alluvial series. The formation and structure of these terraces are the outcome of the location and pattern of river valleys in relation to the morphostructural elements of the KŁD as well as the changes of climate and environmental conditions in the Quaternary. The presented results were obtained owing to the fact that the investigations were conducted both in the profiles of hillslopes (slope environment) and river valleys (fluvial environment) as well as in the bottom of the KŁD (glacial environment). Only such an integrated approach gives an opportunity to find the relationship between the elements of the local litho- and morphogenetic system of the HCM: hillslopes ↔ river valleys ↔ bottoms of structural depressions.

3

Middle and Late Pleistocene terrestrial snails from the Middle Dniester area, Ukraine (based on Mykola Kunytsia’s collections)

Popiuk Yana, Ridush Bogdan, Solovey Tatiana

Geological Quarterly

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2021

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Vol. 65, No. 1

art. no. 6

EN

Extensive collections of land molluscs from the many sections of Middle and Late Pleistocene deposits in the region of the Middle Dniester River were made by Professor Mykola Kunytsia (1925-2002). These collections, now at the Natural Museum, Yuriy Fedkovych Chernivtsi National University, were for the most part analysed, but remained partially unpublished. M. Kunytsia used them for regional reconstructions of palaeolandscapes during various stages of the Pleistocene. In our study, we used these collections to assess the land snail diversity in the region during consecutive stages of the Middle and Late Pleistocene. Our analysis of faunas of cold and warm stages showed that the latter were more diverse. While all or most of the cold stages had many species in common, the faunas of the warm stages were more heterogeneous. Such a feature may play an essential role in Quaternary biostratigraphy.

4

A re-analysis of Chibanian Pleistocene tracks from Vértesszőlős, Hungary, employing photogrammetry and 3D analysis

Tanaka Ikuko, Markó András, Hyodo Masayuki, Strickson Catherine E., Falkingham Peter L.

Annales Societatis Geologorum Poloniae

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2021

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Vol. 91, No. 1

75--83

EN

The Vértesszőlős quarry, the Palaeolithic site where the “Samu” hominin fossil remains (Homo heidelbergensis) were found, is located in North West Hungary. The site is dated between the Early and Middle Pleistocene (ca. 310 ka). A short distance from where the Samu remains were found is an exposed surface of calcareous mudstone, preserving numerous fossil tracks made by a range of mammals and birds. Of particular interest are three elongate impressions - two potentially successive and one isolated. These tracks have previously been referred to either hominin or ursine trackmakers. Since bear pes tracks can superficially resemble human tracks, we attempted to discern the 3D morphology of the traces using digital photogrammetry. Our analysis suggests the isolated impression is likely the product of two superimposed tracks of a cloven hoofed ungulate. However, the two potentially successive tracks are more problematic. The highly weathered surface (first exposed in the 1960’s) has made interpretation difficult. Both impressions seem to possess a narrow, rounded end similar to the posterior heel margin of a human track. At the anterior end the impressions are broader, and bounded by smaller impressions that could be interpreted as toe marks. However, these two tracks differ considerably in their length/width ratios and are too widely spaced to be part of a single bipedal trackway. It is conceivable that one or both of these impressions may be highly weathered hominin tracks. However, given the highly weathered nature of the exposed surface, and the lack of morphological detail in the tracks, we cannot at this time confidently attribute the tracks to any specific trackmaker, despite our digital models of the tracks which provide a relatively objective means of analysis independent of prior assumptions.

5

Intra-individual variability of dental enamel δ13C and δ18O values in Late Pleistocene cave hyena and cave bear from Perspektywiczna Cave (southern Poland)

Czernielewski Michał, Krajcarz Magdalena, Krajcarz Maciej T.

Studia Quaternaria

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2020

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Vol. 37, Nr 2

121--128

EN

An important source of palaeoecological and palaeoenvironmental information is intra-specimen variability of isotopic composition of mammal tooth enamel. It reflects seasonal or behavioral changes in diet and climate occurring during a life of the animal. While well-known in ungulates, in carnivorans this variability is poorly recognized. However, carnivoran remains are amongst the most numerous in the Pleistocene fossil record of terrestrial mammals, so their isotopic signature should be of particular interest. The aim of the study was to verify if enamel of a fossil cave hyena (Crocuta crocuta spelaea) and a cave bear (Ursus ingressus) records any regular inter- or intra-tooth isotopic variability. We examined intra-individual variability of δ13C and δ18O values in permanent cheek teeth enamel of fossil cave hyena and cave bear from the site of the Perspektywiczna Cave (southern Poland). We conclude that the isotopic variability of the cave hyena is low, possibly because enamel mineralization took place when the animals still relied on a uniform milk diet. Only the lowermost parts of P3 and P4 enamel record a shift toward an adult diet. In the case of the cave bear, the sequence of enamel formation records periodic isotopic changes, possibly correlating with the first seasons of the animal life.

6

The history of bears (Ursidae, Carnivora, Mammalia) from Silesia (southern Poland) and the neighbouring areas

Marciszak Adrian Przemysław, Lipecki Grzegorz

Geological Quarterly

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2020

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Vol. 64, No. 4

876--897

EN

Revision of the Silesian bear fauna, based on material from 152 sites, mainly cave and karstic localities, and also archaeological and open-air sites, shows the presence of 13 forms and species. These records encompass the last 16.5 Ma and may be divided into five main morphophyletic groups. The oldest bears, represented by the genera Ballusia and Ursavus, are dated to 16.5-11 Ma, and belonged to the stem forms of the subfamily Ursinae. After a break of 6 My, the earliest members of the genus Ursus appeared, and all known Pliocene bears in Silesia belong to the genus Ursus were identified as Ursus minimus. They represent one or two migration events. Additionally, between 3.6 and 3.2 Ma, a single occurence of Agriotherium insigne was recorded from the Węże 1 site. A few Early Pleistocene bear records are represented by U. etruscus, which was a probable ancestor of both arctoid and spelaeoid bear lineages. The oldest representative of Ursus ex gr. arctos known so far and assigned to U. a. suessenbornensis is known from one latest Early Pleistocene (1.2-0.9 Ma) locality, while other Polish records of this form require confirmation. The first occurrence of U. deningeri, the oldest taxon within the U. ex gr. deningeri-spelaeus lineage, was recorded from ~700 ka deposits in Silesia. During the pronounced cold period of MIS 12, the Scandinavian ice sheet covered almost the entire modern territory of Poland, with the exception of the Sudetes and the Carpathians. The accompanying drastic faunal turnover led to the formation of the pan-Eurasian Mammoth Fauna at ~460 ka. At that time a characteristic member of this fauna, the steppe brown bear Ursus arctos priscus, a specific ecomorph adapted to live in open grasslands, appeared in this region. It survived until the beginning of MIS 1, when modern Ursus arctos arctos appeared in Silesia and survived to the present day. U. deningeri was the most common bear during the Middle Pleistocene, while the first records of U. spelaeus spelaeus appeared since MIS 7. The latter form was replaced by U. ingressus during the Late Pleistocene (~110-100 ka). Spelaeoid bears totally dominated the cave assemblage, and finally vanished between 27 and 24 ka.

7

Magnetostratigraphy and magnetic susceptibility of the best developed Pleistocene loess-palaeosol sequences of Ukraine : implications for correlation and proposed chronostratigraphic models

Hlavatskyi Dmytro V., Bakhmutov Vladimir G.

Geological Quarterly

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2020

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Vol. 64, No. 3

723--753

EN

We provide a revised magnetostratigraphy and magnetic susceptibility stratigraphy of the most complete and thickest (to nearly 60 m) loess-palaeosol sequences in Ukraine spanning the past 1 My: the Roksolany (Black Sea Lowland) and Vyazivok (Dnieper Lowland) sections. The Matuyama-Brunhes boundary has been detected in both sequences in stratigraphically different palaeosol units according to current regional chronostratigraphic schemes. Hypotheses of a large magnetic lock-in depth at Vyazivok and lithostratigraphic incompleteness at Roksolany do not resolve this inconsistency. Instead, new chronostratigraphic models following the Chinese loess designation system, which are supported by correlation of the magnetic susceptibility records with the marine isotope record and estabilished magnetostratigraphic control points, are proposed. We conclude that the Matuyama-Brunhes reversal in the Roksolany and Vyazivok sections belongs to the same palaeosol unit, the Shyrokyne (according to our nomenclature, the U-S7), which corresponds to MIS 19. This novel interpretation resolves the inconsistency of the stratigraphic position of the Matuyama-Brunhes boundary in Ukrainian loess, ends long-standing debate regarding the chronostratigraphy of the Roksolany section, and allows precise correlation of the most representative loess-palaeosol sequences of Ukraine with those in the Danube Basin and the Chinese Loess Plateau. It is considered that the Roksolany Tephra in MIS 6 loess unit can be related to the L2 Tephra which is widely distributed in southeastern European loess records and lacustrine archives. In the light of our results, the Roksolany sequence may serve as a national lectostratotype of the Middle Zavadivka (U-L4) loess unit corresponding to MIS 10. Additionally, a generalized pedostratigraphic column of the past 1 My for central and southern Ukraine has been constructed and correlated with the Hungarian, Serbian and Chinese loess stratigraphies, as well as with the marine isotope record down to MIS 25.

8

Record of the Pleistocene at karst sites of the Świętokrzyskie (Holy Cross) Mountains region – a review

Urban Jan, Hercman Helena, Ochman Katarzyna, Kasza Andrzej

Studia Quaternaria

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2019

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Vol. 36, Nr 2

87--108

EN

The objective of this paper is a review of data on reconstruction of the Pleistocene palaeogeography (environment) and stratigraphy based on studies of karst sites in the Świętokrzyskie (Holy Cross) Mountains. Although the number of known Pleistocene karst sites in this region is small, the investigations of them have played a crucial role in a research of the Pleistocene. The study of the Kozi Grzbiet site provided the first evidences for new climatostratigraphy and classification of glaciations in Poland. The explanation of genesis of cryogenic calcite crystals discovered in Chelosiowa Jama-Jaskinia Jaworznicka cave system started a new direction of palaeoenvironmental reconstructions of the last glacial period. Kadzielnia palaeontological site was one of the first Early Pleistocene fossil assemblages in karst studied in Poland, whereas Raj cave provided abundant palaeontological and archaeological material from the Last Glacial. Other sites are of less scientific importance, however some of them can be used in education and popularisation of geosciences. Small number of already studied sites does not exclude discoveries of next sites of high scientific importance.

9

Large-scale deformations in Neogene deposits near Dobrzyń on the Vistula (central Poland) – thrusting from N/NE or valley-side glaciotectonics in the Płock Basin?

Roman Małgorzata, Żuk Rafał

Studia Quaternaria

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2019

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Vol. 36, Nr 2

147--159

EN

The article is focused on the most recent investigations of glaciotectonic structures in high escarpment exposures of the Vistula valley from Dobrzyń to Kuzki in the western part of the Płock Basin. Deformations involve Neogene and occasionally the Lower Pleistocene deposits and they are not expressed as landforms. Structural investigations and analysis of archival geological data provided new information on the origin of large-scale shear structures. Results obtained are clearly contrary to the concept of Brykczyński (1982) regarding valley-side glaciotectonics in the Płock Basin. An emergence of the extensive zone of serial thrust structures of significant amplitude (up to 100–150 m) was found to have not been controlled by a palaeovalley. A driving mechanism is interpreted as a gravity spreading in front of ice sheets advancing from north-northeast during the South Polish Complex (Dorst-Elsterian).

10

Przegląd skamieniałości kręgowców i flory z terenów dzisiejszej Polski zgromadzonych w Muzeum Historii Naturalnej w Wiedniu

Pawlak Wojciech, Czepiński Łuklasz, Majchrzyk Aleksander, Duk Katarzyna

Przegląd Geologiczny

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2019

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Vol. 67, nr 1

48--55

EN

Current territory of Poland was an exploration area for paleontologists from other European countries throughout the almost entire nineteenth century. A considerable part of findings were stored in institutions located beyond current borders of Poland. We have examined, documented and identified above 350 fossils housed in the Natural History Museum in Vienna (Naturhistorisches Museum Wien). The collection includes paleobotanical and paleozoological specimens from the Little Poland and the Upper Silesia. Some of these specimens are a unique material from the localities which are no longer available.

11

Polskie mołdawity : obecny stan wiedzy i perspektywy nowych znalezisk

Szopa Krzysztof, Brachaniec Tomasz, Karwowski Łukasz

Przegląd Geologiczny

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2019

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Vol. 67, nr 8

662--667

EN

The first Polish moldavites were discovered in 2012. This paper is a summary of the distribution and inventory of these Polish tektites. Up to the present, 28 moldavites have been described from seven different sandpits. These moldavites were deposited in the upper Miocene fluvial deposits of the Gozdnica Formation, as well as in the Pleistocene river terraces. Apart from a typical bottle green colour, moldavites also have other diagnostics features for this class of tektites, such as the presence of bubbles, inclusions oflechatelierite, as well as the same, homogeneous chemical composition. Fluvial redeposition was interpreted as the main process which determined moldavite distribution. Despite the most recent find of one moldavite specimen in Bielawy, all of these specimens indicate both Lusatian as well as sub-strewn Czech fields as their supply area.

12

The provenance of erratic pebbles from a till in the vicinity of the city of Radom, central Poland

Strzelecki Piotr Jan

Geology, Geophysics and Environment

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2019

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Vol. 45, no. 1

21--29

EN

Petrographic analysis, including the indicator erratics count method of coarse pebbles (20–60 mm), was performed for the first subsurface layer of the glacial till in the vicinity of the city of Radom. Crystalline rocks comprise 60% of the sample, whereas carbonate and clastic sedimentary rocks total 18% and 15%, respectively. Among the crystalline rocks, 14% clasts were identified as indicator erratics. The majority of the indictor erratics originated from the Åland region (63%). Significant contributions were also derived from the central Baltic Basin (12%), Ångermanland (9%) and Uppland (9%) regions. Trace amounts are recorded from the northern Baltic, Dalarna and Småland regions. The spatial distribution of crystalline erratic source areas suggests material incorporation into an ice sheet mainly from central-eastern Fennoscandia. The indicator assemblage composition indicates the Odranian (MIS 6) origin of the till. The majority of the erratic sedimentary rocks were derived from the central and southern Baltic Basin while local rocks comprise a minor proportion. The relatively low carbonate clasts content indicates that the till was affected by partial decalcification resulting from post-depositional chemical weathering. This study supplements the results on erratic pebble provenance in the glacial tills of Middle Polish Glaciation Complex in Poland.

13

Skutki zmian klimatu na środowisko jaskiniowe

Kasprowska-Nowak K.

Inżynieria Ekologiczna

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2018

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Vol. 19, nr 6

198--204

PL

W artykule przedstawiono skutki zmian klimatu na środowisko jaskiniowe (ekosystem podziemny) od momentu tworzenia się jaskiń (neogen), przez okres zlodowaceń na obszarze Polski do dnia dzisiejszego. Opracowano je na przykładzie analizy osadów Jaskini na Biśniku (położona w środkowej części Wyżyny Krakowsko-Wieluńskiej), które składają się z kilkunastu warstw zbudowanych z różnorodnych materiałów (geologicznych, paleozoologicznych, paleobotanicznych i archeologicznych) i dostarczają wiedzy na temat przeobrażeń klimatycznych. Dzięki wyróżnionym składnikom (opracowanym przez interdyscyplinarnych badaczy) i przy pomocy wyników datowania warstw osadów metodami fizykochemicznymi, dokonano rekonstrukcji poszczególnych elementów środowiskowych w jaskini (skały krasowiejącej, morfologii, mikroklimatu, wód jaskiniowych, fauny, flory oraz człowieka) w czasie geologicznym, pomiędzy którymi zachodziły określone relacje/ zależności. Wyróżnione elementy tworzyły różne układy (modele) ekologiczne na trzech etapach rozwoju jaskini (abiotycznym, biotycznym i antropicznym), które wydzielono w następstwie zmian klimatycznych.

EN

The article presents the effects of climate change of the cave environment (underground ecosystem) since the formation of caves (Neogene Period), through the glaciation period in Poland to the present day. They were developed on the example of the analysis of the Biśnik Cave sediments (located in the central part of the Cracow-Wieluń Upland), which consist of several layers made of various materials (geological, paleozoological, paleobotanical and archaeological) and provide knowledge about climate change. Thanks to the distinguished components (developed by interdisciplinary researchers) and using the results of dating of sediment layers using physicochemical methods, reconstruction of individual environmental elements in the cave (karstifited rock, morphology, microclimate, cave waters, fauna, vegetation and man) was made during the geological period between which occurred specific relationships / dependencies. The distinguished elements formed various ecological systems (models) at three stages of cave development (abiotic, biotic and anthropic), which developed as a result of climate change.

14

Stratigraphic interpretation of loess in the marginal zone of the Dnieper I ice sheet and the evolution of its landscape after deglaciation (Dnieper Upland, Ukraine)

Komar M., Łanczont M., Fedorowicz S., Gozhik P., Mroczek P., Bogucki A.

Geological Quarterly

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2018

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Vol. 62, No. 3

536--552

EN

Litho-, pedo- and palynological analyses constrained by radiometric dating of two loess-palaeosol sequences, Nahirne and Velyka Andrusivka, exposed in a cliff at the eastern edge of the Dnieper Upland, Ukraine, document regional environmental changes in the western marginal zone of the Dnieper lobe. The postglacial loess sedimentation cycle was initiated during MIS 8, immediately after the ice sheet recession. On the basis of palaeorelief analysis, subsequent morphogenetic stages of the original postglacial relief, associated with the modifying and masking role of the loess, and destructive slope processes were reconstructed. Periglacial steppe with consistently present scattered trees formed the Pleistocene landscape in the Middle Dniester area during the last three glacial periods. In such an environment, the following loess beds, correlated with marine isotope stages (MIS), were deposited: Dnieper (dn) - MIS 8, Tyasmyn (ts) - MIS 6, Uday (ud) - MIS 4 and Bug (bg) - MIS 2. During the last two warm periods: Kaydaky (kd) - MIS 7 and Pryluky (pl) - MIS 5, the landscape was not fully forested. As a result, the individual palynological features of these soils show a diverse character. The TL and OSL dates form a sequence with numerous inversions that are difficult to interpret. Although these data do not significantly influence the interpretation, they show that: 1) there are loesses that undoubtedly formed after the maximum extent of the ice sheet by short-distance transport of dust material from local fresh glacial deposits and the underlying Paleogene rocks; 2) date distortions result from the activities of an exceptionally rich pedofauna that has contaminated the material not only in the soil sections of the profile but also in the adjacent loess. It is possible to delimit a few stages of pedofaunal activity in each of the soil units.

15

Sedimentary evidence for an ice-sheet dammed lake in a mountain valley of the Eastern Sudetes, Czechia

Hanáček M., Nývlt D., Skácelová Z., Nehyba S., Procházková B., Engel Z.

Acta Geologica Polonica

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2018

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Vol. 68, no. 1

107--134

EN

An accumulation of glacial sediments is located near Písečná village in the depression between the Sokol Ridge and Zlaté Hory Highlands NNE of Jeseník town (Eastern Sudetes). The accumulation lies at the lateral side of the mountain valley of the Bělá River and fills a preglacial palaeovalley of this river. Research combining facies analysis of outcrops, ground penetrating radar survey, interpretation drilling survey, and modelling of the preglacial relief was undertaken at the site. According to the results obtained, the upper part of the sedimentary accumulation represents a coarse-grained terminoglacial glaciofluvial delta of the Gilbert type. The development of the accumulation has dominantly been driven by the preglacial morphology. Facies typical for foresets of coarse-grained deltas represented mainly by high-density flows, cohesionless debris flows, debris falls and less common low-density flows were found in the outcrops. The delta near Písečná prograded into a lake dammed by the ice-sheet front in the north. The lake was bounded by the slopes of Sokol Ridge, Zlaté Hory Highlands and Góry Parkowe on other sides. The lake level reached an altitude of up to 430 m a.s.l., as the coarse-grained delta plain base lies at this level.

16

Pleistocene deposits in the Southern Egyptian Sahara: lithostratigraphic relationships of sediments and landscape dynamics at Bir Tarfawi

Hill C. L., Schild R.

Studia Quaternaria

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2017

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Vol. 34, Nr 1

23--38

EN

The sedimentological and lithostratigraphic record from north-central Bir Tarfawi documents the presence of Pleistocene basin-fill deposits. Three topographic basins were created as a result of deflation during climate episodes associated with lowering of the local groundwater table. In each case, the three deflational basins or topographic depressions were subsequently filled with sediments; these basin aggradations coincided with changes from arid climate conditions to wetter conditions and a rise in the groundwater table. The oldest and highest sedimentary remnant is associated with Acheulian artifacts and may reflect spring-fed pond and marsh conditions during a Middle Pleistocene wet climate episode. Lithofacies for a lower stratigraphic sequence (the “White Lake”) documents deposition in a perennial lake that varied in extent and depth and is associated with Middle Paleolithic artifacts. A third episode of deflation created a topographic low that has been filled with Late Pleistocene sediments that are associated with Middle Paleolithic artifacts and fossil remains. Lateral and vertical variations in the lithofacies of this basin-fill sequence and the sediments of the “grey-green” lake phases provide a record of changing hydrologic conditions. These hydrologic conditions appear to reflect variations in water-table levels related to groundwater recharge and, at times, local rains.

17

Zespoły plejstoceńskiej fauny (zbiory Muzeum Geologicznego PIG-PIB) w ujęciu stratygraficznym, geologicznym i tafonomicznym

Woroncowa-Marcinowska K., Pawłowska K., Żarski M., Urban J.

Przegląd Geologiczny

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2017

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Vol. 65, nr 1

53--62

EN

The paper presents 15 collections of bones of mammals (15 sites, 357 specimens) from the Geological Museum of the Polish Geological Institute, which were gathered during the firsthalf of the 20th century. This is the first study of these collections. The remains of J Urban woolly mammoth, woolly rhinoceros, bison, reindeer, horse and predators, and other bones complement the record of their occurrence in central Europe during the last glaciation. The geological position was established for most sites based on both published sources and own research (Kadzielnia and Sitkówka quarries). The collections were obtained from fluvial (woolly mammoth and rhinoceros), aeolian (mammoth remains) and cave sediments (taxonomic diversity of mammals with predominance ofpredators). It has been confirmed that typical Pleistocene sediments of the Kadzielnia quarry occur only in the Jaskinia Jeleniowska Cave and Schronisko nad Przepaścią Cave. The analysis of the literature suggests that the majority of bones representing all collections are ofVistulian (Würm) age, mainly the Grudziądz Interstadial.

18

Cechy sedymentologiczne osadów wodnolodowcowych w żwirowni Łubienica-Superunki (SE części Wysoczyzny Ciechanowskiej)

Giriat D., Smolska E., Woźniak B.

Landform Analysis

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2017

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Vol. 33

25--36

PL

Praca zawiera charakterystykę sedymentologiczną osadów sandrowych występujących pod niewielkiej miąższości gliną lodowcową w południowo-wschodniej części Wysoczyzny Ciechanowskiej, w pobliżu strefy krawędziowej z doliną Narwi. W artykule przedstawiono opis sekwencji struktur sedymentacyjnych widocznych w żwirowni Łubienica-Superunki i próbę interpretacji warunków transportu i depozycji osadów wodnolodowcowych. Występują tu dwa kompleksy osadów, z których dolny był akumulowany w roztoce piaskodennej, a górny w roztoce o większej dynamice przepływów (ze znacznie większym udziałem żwirów) przed nasuwającym się czołem lądolodu.

EN

This paper presents the sedimentological characteristics of outwash sediments occurring under a glacial till of a small thickness, in the south-eastern part of the Ciechanowska Upland, near the edge of the Narew Valley. The article presents description of the sequence of sedimentation structures visible in the Łubienica-Superunki quarry. There are two complexes of fluvioglacial sediments. The bottom part visible in the studied outcrops were accumulated in sand-bed braided river whilst the upper part of sediments developed in sandy-gravel braided river of a greater flow dynamics (near front of the warta ice sheet margin).

19

Pleistocene glaciations of the SE Altai, Russia, based on geomorphological data and absolute dating of glacial deposits in Chagan reference section

Agatova A. R., Nepop R. K.

Geochronometria

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2017

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Vol. 44, no. 1

49--65

EN

Geomorphological evidence of at least two Pleistocene glacial epochsis noted within the Chagan-Uzun river basin, SE Altai. A review and analysis of all available absolute dates for reference Chagan section is presented. The highest correlation amongst all TL dates is observed for the lens of glacio-lacustrine sediments – the most suitable among glacial deposits for luminescence dating, and indicates its possible Middle Pleistocene age. IRSL dates obtained from feldspar indicate a Middle Pleistocene age of moraines already in the upper part of the section. The small number of obtained IRSL dates does not allow making geochronological reconstructions of the Pleistocene glaciations, but gives the possibility for further experiments with different variation of OSL (IRSL) techniques. Strong low temperature peak in TL signal and strong response to IR stimulation are specific regional quartz features, which could be explained by combination of short transportation distance and low number of depositional cycles for mineral grains. Available radiocarbon dates of carbonate concretions from this section are not related to the age of moraine sedimentation and most likely indicate the period of the Chagan river incision into the ancient glacial deposits. This study has shown that TL method is not valid for dating glacial sediments and TL dates cannot be utilized as chronostratigraphic markers. Generally, the Chagan section could hardly serve as a reference section for the Altai stratigraphy; available depositional correlation schemes for the Russian Altai and Siberia which are based on several TL dates obtained in the last century needs to be improved.

20

New luminescence-based geochronology framing the last two glacial cycles at the southern limit of European Pleistocene loess in Stalać (Serbia)

Bösken J., Klasen N., Zeeden Ch., Obreht I., Marković S. B., Hambach U., Lehmkuhl F.

Geochronometria

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2017

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Vol. 44, no. 1

150--161

EN

A new geochronology was established for the Stalać loess-paleosol sequence (LPS) in Serbia. The section is located in the interior of the Central Balkan region, south of the typical loess distribution, in a zone of paleoclimatic shifts between continental and Mediterranean climate regimes. The sampled sequence contains four well-developed paleosol and loess layers, a crypto tephra and one visible tephra layer. Optically stimulated luminescence measurements showed a strong dependency of preheat temperature on equivalent dose for one fine-grained quartz sample, which makes it unsuitable for dating. A firm chronology framing the last two glacial cycles was established using finegrained polyminerals and the post-infrared infrared stimulated luminescence (pIR50IR290) protocol instead. The characteristics of dated paleosols indicate similar climatic conditions during the last interstadial and interglacial phases, which were different from the penultimate interglacial period. The tephra within the L2 loess, probably related to tephra layers also found in other sections in Southeastern Europe, was sandwich-dated. The results indicate an age between 118 ka and 141 ka. Furthermore, a weak pedogenic layer dated to between 126 ka and 148 ka gives a first numerical age to this soil formation in Southeastern Europe.