Wyniki wyszukiwania - BazTech

1

Depositional conditions of the Upper Younger Loess during the Last Glacial Maximum in central and eastern Europe

Dzierżek Jan, Lindner Leszek, Chlebowski Roman, Szymanek Marcin, Bogucki Andriy, Tomeniuk Olena

Acta Geologica Polonica

|

2022

|

Vol. 72, no. 4

369--389

EN

This paper is a summary of the results of research on the accumulation conditions of the Upper Younger Loess (LMg) in Poland and Bug loess (bg) in Ukraine from the maximum stage (MIS 2) of the Vistulian (Weichselian) Glaciation in central and eastern Europe. These studies included an analysis of the morphological (topographic) situation of the loess cover, its grain size and heavy mineral composition, the preserved structures of loess sedimentation as well as mollusc and pollen analyses of this loess. They revealed that the accumulation of Upper Younger Loess (UYL) might have been more dependent on the prevailing moisture conditions than previously thought. These conditions could have been caused by cold air masses from an ice sheet and warm air masses from the Mediterranean Sea and Atlantic coming together in the Carpathians and the Holy Cross Mountains and favouring the formation of dust storms and precipitation. In this process, a loading of loess dust (formed from local rocks weathering in periglacial conditions) by atmospheric moisture particles was especially significant. The moist substrate not only favoured the periodic development of vegetation and molluscs but also enabled the interception of dust and the accumulation of an increasingly thick loess cover. Westerly and south-westerly winds predominated in the UYL as indicated by the topographic position of loess patches and the mineral composition of the studied loess. Periodically an increased air circulation from the east and northeast occurred.

2

The maximum ice sheet extent and its retreat in the western part of the Holy Cross Mountains, Poland, during the Sanian 2 Glaciation/MIS 12 based on geological data and analysis of karst phenomena

Dzierżek Jan, Lindner Leszek, Cabalski Krzysztof, Urban Jan, Cyglicki Michał

Acta Geologica Polonica

|

2021

|

Vol. 71, no. 2

199--218

EN

The paper is focused on the palaeographic development of the western part of the Holy Cross Mountains, Poland, during the maximum extent of the Sanian 2 (MIS 12) ice sheet and its retreat. The studies were based on archival cartographic data, coupled with new lithological and petrographic analyses of limni- and fluvioglacial sands, i.e., grain-size composition, quartz grain morphology and heavy mineral analysis, as well as analysis of the erratic material of tills. The results confirm the regional variability of the erratic material in the Sanian 2 tills and point to the long-term development of fluvioglacial sands cover documenting cold climate conditions. They also evidence that the western part of the Holy Cross Mountains was the area where two oppositely directed ice sheet lobes (Radoszyce and Sandomierz) advanced during the Sanian 2 Glaciation and that deglaciation of the area took place in two stages. Huge quantities of meltwater released at that time contributed to the intensification of earlier initiated karst phenomena, as well as filling of the existing caves by fluvioglacial sands.

3

Stratigraphy and conditions of accumulation of the Younger Loesses (Vistulian) in the Holy Cross Mountains area, Poland

Dzierżek Jan, Lindner Leszek

Studia Quaternaria

|

2020

|

Vol. 37, Nr 2

109--120

EN

The paper presents results of studies focused on occurrence and correlation of four main horizons of Younger Loesses: Lowest Younger Loess (LMn – after Maruszczak, 2001), Lower Younger Loess (LMd), Middle Younger Loess (LMs), and Upper Younger Loess (LMg) recorded in five sections (Politów, Wąchock, Nietulisko Małe, Komorniki and Bodzechów) in the Holy Cross Mountains area. All analysed loesses were accumulated during the Vistulian Glaciation (Weichselian). The horizons were distinguished based on separating interstadial tundra soils, coupled with thermoluminescence dating, and correlated with marine oxygen-isotope stages MIS 5d−2. The Lowermost Younger Loess (LMn) covers the Nietulisko I soil complex (Jersak, 1973), developed on deposits of the Odranian Glaciation (MIS 6) and representing a forest soil of the Eemian Interglacial (MIS 5e) and the Brørup warming (MIS 5c). A thin horizon of the Oldest Younger Loess and a thin sandy horizon, both probably corresponding to the Herning cooling phase (MIS 5d) at the boundary with the Eemian Interglacial, were distinguished within this complex. Based on previously performed grain-size and heavy mineral analysis of the Upper Younger Loess (LMg) and a topographic position of the loesses in four loessy islands of diverse regional extent, accumulation of this loess in the Holy Cross Mountains area is found to have been stimulated by the western winds. The proposed model of loess accumulation takes into account the influence of the topography of the area and its geological structure.

4

The loess section in Wąchock as the key site of Vistulian loesses and palaeosols in the Holy Cross Mountains (Poland)

Dzierżek Jan, Lindner Leszek, Nawrocki Jerzy

Geological Quarterly

|

2020

|

Vol. 64, No. 2

252--262

EN

The Wąchock section (N part of the Holy Cross Mountains) is bipartite, with a sub-loess lower part and a loess upper part. The sub-loess part lying on Lower Triassic sandstones includes fluvial, glacial and ice-dammed lake deposits, TL-dated at 352 ky BP to 157 ±23 ky BP. They represent the Mazovian (MIS 11) (Zbójnian?, MIS 9?) Interglacial and the Odranian Glaciation (MIS 6). The upper part comprises loesses intercalated with palaeosols, which reach a total thickness of 9 m and have TL ages at 148 ±23 ky BP to 15.8 ±8 ky BP. This part of the succession begins with horizon B of a brown soil from the Eemian Interglacial (MIS 5e) with an interstadial black soil from the oldest Vistulian (MIS 5c). Four younger loess horizons from the middle and younger Vistulian occur above; loesses with arctic and tundra palaeosols correspond to younger isotope stages (MIS 5b-MIS 2). The loess and palaeosol horizons distinguished in Wąchock were correlated with loess sections in Poland (Zwierzyniec and Polanów Samborzecki) and western Ukraine (Kolodiiv 3), showing large similitarities of both loesses and palaeosols. Due to this, the Wąchock site is proposed as a one of key sections for Vistulian loess sequences not only in the Holy Cross Mts. region but also in Central Europe. Palaeomagnetic studies of the Wąchock loesses have registerered palaeomagnetic inclinations with values lower than the average values expected in this locality (63°).

5

Quaternary valley levels and river terraces in the western part of the Holy Cross Mountains

Dzierżek Jan, Lindner Leszek, Cabalski Krzysztof

Studia Quaternaria

|

2019

|

Vol. 36, Nr 2

109--118

EN

According to the current state of research five sand-gravel accumulation levels of Quaternary age are visible in the morphology of the western part of the Holy Cross Mountains, within the Wierna Rzeka, Hutka and Bobrza river valley systems and the lower stretches of the Biała Nida and Czarna Nida river valleys. Two upper levels (V and IV) correspond to valleys formed during the Odranian Glaciation-Saalian, MIS6 and its reccesional phases under the influence of proglacial and extraglacial waters beyond the extent (to the east) of the maximal ice-sheet limit of this glaciation, reaching to the present-day Leśnica-Gnieździska-Łopuszno line. Two lower levels (III and II) are terraces that were typically formed during the climatic conditions thatprevailed during Vistulian stadials. Sands and gravels of the three upper levels (V−III) contain numerous debris flow deposits and cryoturbation structures documenting periglacial conditions during their accumulation. The lowermost level (I) is a typical Holocene floodplain.

6

Pleistocene deposits in the western part of the Holy Cross Mountains

Lindner Leszek, Dzierżek Jan

Studia Quaternaria

|

2019

|

Vol. 36, Nr 2

75--85

EN

The paper presents characteristics of the Pleistocene sediments in the western part of the Holy Cross Mountains. They are subdivided into four complexes and their stratigraphic setting is referred to the updated scheme for the Pleistocene of Poland. The Preglacial Complex includes fluvial sediments characteristic for its lack of Scandinavian material. Sediments of three main glaciations (Nidanian, Sanian 1 and Sanian 2) within the South Polish Complex, are referred also as the South Polish Glaciations. The oldest of these glaciations (Nidanian) is separated from the middle glaciation (Sanian 1) by sediments of the Podlasian Interglacial, represented by clay at the Kozi Grzbiet Cave that contains faunal remains and record of the Brunhes/Matuyama palaeomagnetic boundary. During the middle (Sanian 1) and youngest glaciation (Sanian 2), the Holy Cross Mountains were almost completely covered by the Scandinavian ice sheet, forming glacial deposits separated by fluvial series of the Ferdynandovian Interglacial. The Middle Polish Complex begins with sediments of the Mazovian Interglacial, represented by a pollen record from the Zakrucze site. They are followed by deposits of periglacial and fluvial origin of the Liwiecian Glaciation, Zbójnian Interglacial, Krznanian Glaciation and Lublinian Interglacial. The following glaciation (Odranian) is represented by the youngest glacial deposits that document presence of the Scandinavian ice-sheet in the westernmost part of the Holy Cross Mountains. The North Polish Complex is composed of a climatic warming (Eemian Interglacial) and cooling (Vistulian Glaciation), and is represented by valley and periglacial deposits. The last cooling of the Pleistocene is recorded in faunal remains in the Raj Cave.