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1

Stratygrafia, petrografia i paleogeografia glin lodowcowych w rejonie północno-zachodniego wybrzeża Polski

100%

Krzyszkowski D.

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tom nr 438

51--91

PL

Na obszarze północno-zachodniego wybrzeża Polski udokumentowano 10 różnowiekowych poziomów glin lodowcowych: dwa z najstarszych zlodowaceń, trzy ze zlodowaceń południowopolskich, trzy ze zlodowaceń środkowopolskich i dwa z ostatniego zlodowacenia. Dla niektórych poziomów stratygraficznych zdefiniowano na podstawie ich składu petrograficznego różne typy regionalne glin lodowcowych, z których niektóre niewątpliwie wyznaczają zasięgi oddzielnych lobów lodowcowych. Część wydzielonych typów glin posiada takie same cechy składu petrograficznego jak gliny w regionie szczecińskim. Dla innych typów glin opisano cechy specyficzne tylko dla regionu północno-zachodniego wybrzeża i te poziomy zdefiniowano formalnie, wskazując dla nich profile stratotypowe, cechy przewodnie i zasięg regionalny. Występowanie większości poziomów glin jest w regionie północno-zachodniego wybrzeża sporadyczne i zazwyczaj nie tworzą one ciągłych horyzontów. Różne loby lodowcowe udokumentowano dla najmłodszego stadiału zlodowacenia południowopolskiego, najmłodszego stadiału zlodowacenia środkowopolskiego oraz dla faz leszczyńskiej i poznańsko-pomorskiej stadiału głównego ostatniego zlodowacenia. Występowanie wyraźnie zaznaczonych lobów lodowcowych, szczególnie dla awansów ze wschodu lub północnego-wschodu, jest związane z pozycją na obrzeżu niecki południowego Bałtyku, gdzie następuje rozdzielenie lobów na te, które kontynuują awans w kierunku zachodnim (do NW Niemiec i Danii) oraz te które zmieniają kierunek awansu na południowy zachód i południe wzdłuż doliny Odry (lob Odry, do południowo-wschodnich Niemiec i zachodniej Polski). Ponadto, na obszarze północno-zachodniego wybrzeża, występują morskie utwory interglacjału eemskiego. Są to osady ilasto-mułkowe i piaszczyste z fauną mięczaków morskich, reprezentujące facje przybrzeżne (lagunowe, plażowe) i występujące na głębokości od 5,5–19,6 m pod poziomem współczesnego morza. Zasięg tych osadów wskazuje na istnienie zatoki morskiej wciętej na około 10 km w głąb lądu, być może uformowanej w dawnej rynnie glacjalnej.

EN

There are 10 till horizons of different ages in the northwestern coastal region of Poland, representing the “oldest” glaciation (2 horizons), Elsterian glaciation (3), Saalian glaciation (3) and the last glaciation (2). Some stratigraphic horizons contain tills of regionally variable petrographic composition, which usually represent tills from different lobes of the same ice sheet advance. Several till horizons have features similar to the tills defined in the southern part of the Szczecin region, others have a petrographic composition specific only to the northwestern coastal region of Poland. The last ones have been newly and formally defined, with an indication of stratotype sections, characteristic features and extents. In the northwestern coastal region of Poland, the till horizons occur sporadically and they do not form continuous beds. Glacial lobes have been proved for the late Elsterian, late Saalian and for both Weichselian advances. Their occurrence (especially during the latest advances coming from the northeast or east) is due to their location in the southern Baltic basin, where the ice sheets differentiated into the lobes that continued their advances towards the west to NW Germany and Denmark, and those that deflected along the Odra river valley (Odra lobe) towards the SW and south to SE Germany and western Poland. Moreover, Eemian marine sediments, clay or sand with mollusc fauna have been found in the northwestern coastal region. They occur at a depth of 5.5–19.6 m below the present-day sea level. They were deposited in a shallow bay extending about 10 km inland. The location of these sediments suggests a marine transgression into a pre-existing tunnel valley.

2

Middle and Upper Weichselian Pleniglacial fluvial erosion and sedimenta- tion phases in Southwestern Poland, and their relationship to Scandinavian ice sheet build-up and retreat

63%

Krzyszkowski D. , Kuszell T.

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tom Vol. 77, No 1

17-38

EN

The sequence of Weichselian sediments and processes in SW Poland is almost identical to that of central Poland. Generally, three fluvial units occur, comprising silts and sands coarsening upwards to silts, sands and gravels, with aeolian deposits on top. This suggests very uniform processes throughout the palaeogeographic zone. To the south of this zone, there was extensive loess deposition and glacial deposition to the north. Climatic conditions during the Middle and Upper Weichselian Pleniglacial in SW Poland were similar to those in central Poland and northwestern Europe, though the period of 47-43 kyrs BP was slightly milder in SW Poland (shrub tundra, forest-tundra). Climatic conditions during the periods 38-27 kyrs BP and 23-18 kyrs BP were very uniform throughout central Europe, including SW Poland, though there may have been a strong north-south climatic gradient during the former period, as data from the loessic zone indicate at least patches of boreal forest or forest-tundra conditions in SW Poland at that time. It is also possible that there was a Middle Weichselian Pleniglacial interstadial with a lower age boundary at 25,900 ą 700 years BP, characterised by Pinus-Picea forest with no heliophytes. This interstadial represents the last mild period before the advance of the late Weichselian ice sheet into SW Poland. The Weichselian fluvial deposition of SW and central Poland may have been punctuated by at least three major erosional phases, characterised by similar incision depths during the cold stages. Erosion took place, with certainty, at around 75-60 kyrs BP (Lower Pleniglacial) and 27 kyrs BP, very probably at around 23/22 kyrs and possibly at around 40 kyrs BP, and valley aggradation occurred during the milder stages. The Upper Pleniglacial was characterised by valley aggradation, associated with southward ice sheet advance and restricted fluvial outflow. However, the frequent Middle Pleniglacial Weichselian climatic oscillations did not initiate sedimentation and erosion, they controlled only river discharge and type of fluvial sedimentation and aeolian activity. The occurrence of the erosional and aggradational phases were controlled by the changes in ice volume in Scandinavia, ice sheet build-up and retreat, respectively.

3

Till base deformation and fabric variation in Lower Rogowiec (Wartanian, younger Saalian) Till, Bełchatów outcrop, central Poland

63%

Allen P. , Krzyszkowski D.

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tom Vol. 78, No 1

19-35

EN

We documented that the Wartanian (younger Saalian) Lower Rogowiec Till exposed at Bełchatów, central Poland, is not sedimentologically or structurally homogeneous, and suggested that the till macrofabric patterns and deformation structures may be related to stress conditions in the glacier at the time of deposition. The distribution of deformation structures below and within the till forms a pattern, most probably associated with compressive flow and/or with stronger stress reaction, creating stronger fabrics, above clay beds due to high pore water pressure. The intervening areas, lacking deformation structures, occur between the zones of compression, where pressure would have been less. These patterns occur in a repeated sequence along the sections, which suggests that there may be a control, such as basal glacier stress conditions. The sites showing deformation occur about every 10–20 m. This could imply that the zones of shearing at the ice front have a similar spacing. There are no features in the pattern of the till macrofabrics and deformation structures to suggest that the local Kleszczów Graben or a pre-existing valley had any effect on the mode of till deposition.

4

Nowe stanowiska interstadialu Pilicy [formacja Chojny] w odkrywce Belchatow.

63%

Krzyszkowski D. , Nita M.

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nr 11

788-797

5

Late Cainozoic evolution of the Nysa Klodzka River system between Klodzko and Kamieniec Zabkowicki, Sudetes Mts, Southwestern Poland

51%

Krzyszkowski D. , Przybylski B. , Badura J.

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nr 2