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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.
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.
3
Content available Skutki zmian klimatu na środowisko jaskiniowe
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.
EN
The present study revolves around the identification of the stratigraphical boundary between Pleistocene formations that formed prior to the first advance of the Scandinavian ice sheet (Early Pleistocene, i.e., the so-called preglacial) and the overlying, glacially derived deposits (Middle Pleistocene). In particular, it focuses on variation in heavy mineral assemblages, which are an important tool for stratigraphers. The Neogene basement, described here, was most often the source of material that was redeposited by Early Pleistocene rivers. The geological structure and Early Pleistocene palaeogeographical scenarios for various Polish regions are discussed. Moreover, comparisons with other European preglacial formations are carried out. The mineral spectrum of Lower Pleistocene deposits is largely dependent of rocks of the Neogene and Mesozoic basement. If the incision of ancient catchments was into terrigenous rocks, the stratigraphical boundary between preglacial and glacial formations is easily determined with the help of a heavy mineral analysis. As a rule, this coincides with a noticeable change from resistant to non-resistant mineral associations. Such cases are noted for successions in central Poland and eastern England. On the other hand, outcrops of igneous or metamorphic rocks exist within preglacial river catchments in most parts of Europe. They were the local sources of non-resistant heavy minerals long before their glacial supply from the Baltic Shield. In these cases, mineralogical analysis fails in the search for the Early/Middle Pleistocene transition.
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).
EN
The paper presents general climate changes during the last 2.6 Ma in the Northern Hemisphere. Plant formations of warm intervals (interglacials and interstadials) are briefly described. Disappearance of some more climate-sensitive tree taxa as well as climate changes during the Pleistocene in Northern Europe are also portrayed.
EN
Climate changes during the Pleistocene were driven by large-scale orbital perturbations as well as by internal feedbacks on the Earth. One of the main roles in climate modelling is played by the Southern Ocean that is a great source of sea ice, carbon dioxide, dissolved silica and nutrients. Numerous sediment and ice records derived from the Southern Ocean and Antarctica document high-resolution climatic changes that allow us a better understanding of global climate evolution. Consistently with the global climatic trend, several sea surface temperature (SST) records of the Southern Ocean are marked by a distinct shift from low to high glacial/interglacial variability around Termination V (T V), called the Mid-Brunhes Event (MBE). Prior to T V, the Southern Ocean’s SST displays lower values and low variability. It points to a distinct expansion of the Southern Ocean cold water masses and positional changes of hydrographical fronts during most of the lower Middle Pleistocene, which started in the Pliocene. Beside large climatic changes, several abrupt distinct warming and cooling phases have been recognized. Some of them (MIS 22–19, MIS 11 and MIS 5) show similarities to MIS 1, which could be used for future climate predictions. In this paper we would like to present the middle and late Pleistocene climatic mechanisms in the Southern Ocean, and to show SST changes in relation to the hydrographic frontal movement, sea ice development and CO2 oscillations.
8
EN
Though the stratigraphical and palaeogeographical framework of the Quaternary in Poland is still to be completed, several crucial points have been confirmed recently. The preglacial series, accepted for years as belonging to the Lower Pleistocene, is undoubtedly of Early Pliocene age, with a huge hiatus above almost until the uppermost Lower Pleistocene. The earliest glaciation in Poland (Nidanian) occurred at about 900 ka BP when the ice sheet reached the mid-southern part of the country. The following Podlasian Interglacial embraced the Brunhes/Matuyama boundary in the middle, in a similar fashion to the corresponding Cromerian Complex in Western Europe. The late Early and early Middle Pleistocene interglacials in Poland comprised 2-3 optima each, whereas every one of the younger interglacials was characterised by a single optimum only. The Late Vistulian ice sheet was most extensive in the western part of Poland (Leszno Phase) whereas the younger Poznań Phase was more extensive in the central and eastern part of the country. This was due to the varied distance from the glaciation center in Scandinavia, making the ice sheet margin reach a terminal position in different times. Palaeoclimatological research in the Tatra Mountains has provided new evidence for the atmospheric circulation over Europe. During cold phases of the Pleistocene in Poland a continental climate extended further westwards, quite the opposite that occurring during warmer intervals.
PL
W artykule dokonano rekonstrukcji elementów krajobrazu Doliny Wodącej (rzeźby terenu, gleb, wód, szaty roślinnej, zwierząt oraz człowieka) w paleolicie środkowym i górnym (starsza epoka kamienia), który nawiązuje do plejstocenu (tj. od czasu zlodowaceń środkowopolskich do schyłku zlodowacenia północnopolskiego). W pracy bazowano na wynikach interdyscyplinarnych badań osadów Jaskini na Biśniku (uchodzi za jedno z najlepiej zbadanych i najstarszych stanowisk archeologicznych w Polsce), w których wystąpiły zabytki paleolityczne (warstwy 17-4).
EN
In the article made reconstruction of landscape of the Wodąca Valley (relief, soil, water, vegetation, animals and man) in the Middle and Upper Palaeolithic, which corresponds to the Pleistocene (since the Mid-Polish Glaciation until the North-Polish Glaciation). The study was based on the results of interdisciplinary research of the Biśnik Cave sediments (considered one of the most studied and oldest archaeological sites in Poland), where there were the Palaeolithic artifacts (layers 17-4).
EN
The identification of depositional conditions and stratigraphical position of glacigenic deposits in the Napęków area is important for the genetic and stratigraphical interpretation of Quaternary deposits in the central part of the Holy Cross Mountains, as well as for a revision of the course and extent of Middle Polish (Saalian) glaciations. These deposits comprise a series of diamictons which occur between sandy-gravelly deposits. Based on results of macro- and microscopic sedimentological investigations, analysis of heavy mineral composition, roundness and frosting of quartz grains, as well as OSL dating, this complex must have formed during the Odranian Glaciation (Drenthe, Saalian, MIS 6). Sandy-gravelly deposits are of fluvioglacial and melt-out origin. Diamictons represent subglacial traction till. Their facies diversity is a result of variations in time and space, complex processes of deposition and deformation, responsible for their formation at the base of the active ice sheet. This glacigenic depositional complex was transformed by erosion-denudation and aeolian processes in a periglacial environment during the Vistulian (Weichselian, MIS 5d-2).
EN
During the Pleistocene the Scandinavian ice sheet drained huge quantities of sediment-laden meltwaters. These meltwaters supplied ice-marginal valleys that formed parallel to the front of the ice sheet. Not without significance was the supply of ice-marginal valleys from extraglacial rivers in the south. Moreover, periglacial conditions during and after sedimentation in ice-marginal valleys, the morphology of valley bedrocks, and erosion of older sediments played important roles in the depositional scenarios, and in the mineralogical composition of the sediments. The mechanisms that controlled the supply and deposition in ice-marginal valleys were analysed on the basis of a Pleistocene ice-marginal valley that was supplied by northern and southern source areas in the immediate vicinity. Investigations were conducted in one of the largest ice-marginal valleys of the Polish-German lowlands, i.e., the Toruń-Eberswalde ice-marginal valley, in sandurs (Drawa and Gwda) supplied sediments and waters from the north into this valley, and on extraglacial river terraces (pre-Noteć and pre-Warta rivers), formed simultaneously with the sandurs and ice-marginal valley (Pomeranian phase of Weichselian glaciation) supplied sediments and waters from the south into this valley. A much debated question is how similar, or different, depositional processes and sediments were that contributed to the formation of the Toruń-Eberswalde ice-marginal valley, and whether or not it is possible to differentiate mostly rapidly aggraded sandur sediments from ice-marginal valley sediments. Another question addresses the contribution of extraglacial feeding of the Toruń-Eberswalde ice-marginal valley. These matters were addressed by a wide range of analyses: sediment texture and structure, architectural elements of sediments, frequency of sedimentary successions, heavy-mineral analysis (both transparent and opaque heavy minerals), analysis of rounding and frosting of quartz grains, and palaeohydrological calculations. Additionally, a statistical analysis was used. The specific depositional conditions of distribution of sediments in ice-marginal valley allow to distinguish new environment of ice-marginal valley braided river. The spectrum of depositional conditions in the Toruń-Eberswalde ice-marginal valley and their specific palaeohydraulic parameters allow to distinguish three coexisting zones in the ice-marginal valley braided-river system: (1) deep gravel-bed braided channel zone with extensive scours, (2) deep sand-bed braided channel zone with transverse bars, and (3) marginal sand-bed and gravel-bed braided channel zone with diamicton and breccia deposition, which were characterised in detail. Some of the results have been published previously, which is why they are discussed in the present paper within the context of new data.
EN
Samples collected from Late Pleistocene varved clays of the Vistulian (Weichselian) glaciation exposed at Lębork and Złocieniec (Gardno and Pomeranian phases, respectively) yielded palynological contents that are related to the different lithologies composing the varves. The dark-coloured clay units contain very small amounts of palynological material. The lighter-coloured, much thicker coarser units yielded large amounts of organic particles consisting of predominantly palynodebris of terrestrial plants, sporomorphs and aquatic palynomorphs. The latter include fresh-water and marine phytoplankton. All particles were presumably washed out from the pre-Quaternary basement or from erratic material. This is indicated by the dinoflagellate-cyst assemblages, which represent Cretaceous and Palaeogene taxa. The large amounts of organic particles in the light-coloured layers indicate high-energy meltwaters streams, which washed them out, transported them and deposited them in ice-dammed lakes. The barren layers and those with lower amounts of organic particles were deposited during calm, presumably winter, periods, when the energy of the meltwater streams was much lower.
EN
An atypical lithological development of outwash deposits in the Carpathians Foreland (S Poland) shows lower and middle parts of the sedimentary succession that are characterized by sinuous palaeochannels. This channel facies consists of laterally accreted sands derived from side bars. The sedimentary environment was a proglacial system of anabranching channels, presumably of anastomosed type. The outwash channel pattern was most probably controlled by the raising base level of the fluvial system. Both proglacial and extraglacial waters were dammed by a sandur within a small upland valley. Aggradation and progradation of the glaciofluvial deposits resulted in progressive rising of the dammed lake level. The low hydraulic gradient of the outwash streams resulted in a sinuous planform as well as a lowenergy style of deposition. Afterwards, the rising lake water was drained off through a low watershed and the entire valley became filled with outwash sediments. The bedrock morphology thus became buried and a typical unconfined sandur with a braided channel network developed during the last phase of the glaciomarginal sedimentation (upper part of the sedimentary succession under study).
EN
The potential usefulness of taphonomical research for studies of Pleistocene mammal remains is detailed. The required taphonomical research involves two stages. The first one is the biostratinomical stage, which concerns the time between the death of the organism and its burial; for this time-span, the spatial distribution of the remnants is analysed, as well as the weathering marks, the activity of predators (i.e. gnawing and digestion), the influence of temperature, intentional human activity, rodent marks (i.e. gnawing), and trampling. in the second one is the diagenetic stage, which deals with the time-span from the burial of the remnants to their discovery; for this time-span, the influence of physical and chemical processes (including diagenetic alterations of the deposit, the influence of water, and plant-root marks) are considered. The application of taphonomical analysis provides the possibility of reconstructing the environmental conditions under which the skeleton or bone complex was preserved, as well as the depositional history of the bones (postconsumption remnants, flood remains, accumulation of bones by predators). This opens new possibilities for the study of Pleistocene bones in Poland.
EN
The depositional conditions of kame terraces in a mountain valley were analysed sedimentologically and petrologically through a series of kame terraces in the Rudawy Janowickie mountains. The kame terraces comprise five lithofacies associations. Lithofacies association GRt, Sp originates from deposition in the high-energy, deep gravel-bed channel of a braided river. Lithofacies association GC represents a washed out glacial till. Probably a thin layer of till was washed out by sandy braided rivers (Sp). The fourth association (Fh, Fm) indicates a shallow and quite small glaciomarginal lake. The last association (GRt, GRp) indicates the return of deposition in a sandy-bed braided channel. The petrography of the Janowice Wiekie pit and measurements of cross-stratified beds indicate a palaeocurrent direction from N to S. The Janowice Wielkie sedimentary succession accumulated most probably during the Saalian (Odranian, Saale I, Drenthe) as the first phase of ice-sheet melting, because the kame terrace under study is the highest one, 25-27 m above the Bóbr river level. The deposits under study are dominated by local components. The proglacial streams flowed along the margin of the ice sheet and deposited the kame terrace. The majority of the sedimentary succession was deposited in a confined braided-river system in quite deep channels.
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.
PL
Zestawiono wyniki badań geologicznych prowadzonych w odsłonięciu Baruchowo, usytuowanym w zboczu wysoczyzny morenowej obramowującej od południa Kotlinę Płocką. Szczegółowej analizie poddano bezwapienne, kwarcowe piaski i piaski ze żwirem, niezawierające materiału skandynawskiego, wypełniające kopalną dolinę wyciętą w neogeńskich iłach i odsłaniające się w dolnej części stanowiska w Baruchowie. Skład mineralny frakcji ciężkiej i charakter mineralno-petrograficzny piasków i żwirów wyraźne odróżniają je od osadów plejstocenu glacjalnego, co w powiązaniu z ich sytuacją geologiczną pozwala uznać, że są to utwory preglacjalne sensu lato. Na podstawie badań sedymentologicznych, strukturalnych i teksturalnych określono, że analizowane utwory reprezentują dwudzielną serię osadów korytowych piaskodennej rzeki roztokowej, odprowadzającej wody ku północnemu zachodowi. Górna część serii rzecznej to osady fluwioperyglacjalne, charakteryzujące się dominacją ziaren kwarcu o obróbce eolicznej. Ich akumulacja zachodziła w warunkach zimnego, suchego klimatu, bez śladów bezpośredniego wpływu lądolodu, w okresie długotrwałego rozwoju procesów eolicznych w którymś z zimnych pięter dolnego plejstocenu. Czas funkcjonowania rzeki roztokowej i depozycji serii aluwialnych mógł przypadać na schyłek kompleksu preglacjalnego (dolna część serii) po okres panowania warunków peryglacjalnych, poprzedzających transgresję lądolodu zlodowacenia narwi (strop serii), lub tylko na okres zlodowacenia narwi. Nie można też wykluczyć, że akumulacja serii rzecznej nastąpiła dopiero na początku zlodowacenia sanu, poprzedzając wkroczenie pierwszego lądolodu w obszar Kotliny Płockiej. Datowania TL piasków rzecznych z Baruchowa wykazały, że są to osady starsze od 1000 ka.
EN
The paper presents the results of geological investigations carried out at the Baruchowo exposure situated in the slope of the morainic plateau framing the Płock Basin from the south. Non-calcite quartz-dominated sand and gravelly sand were examined in detail. The deposits are devoid of Scandinavian material. They fill a palaeovalley channelled in Neogene clays and are exposed in the lower part of the Baruchowo exposure. Mineral composition of the heavy fraction and petrography of the sands and gravels clearly distinguish the series from Pleistocene glacial deposits, and together with their position in the geological section they suggest that these are preglacial deposits sensu lato. Sedimentological, structural and textural investigations indicate that this is a bipartite series of channel deposits of a sand-bed braided river flowing to the NW. The uppermost part of the river series (B1b) represents fluvioperiglacial deposits dominated by round matt quartz grains, indicative of aeolian origin. Their accumulation proceeded under cold and dry climate conditions without a direct ice sheet effect and during a long-term aeolian process at the beginning of some cold period of early Pleistocene time. The braided river system and deposition of the alluvial series may have occurred from the end of the Preglacial Complex sedimentation (lower part of the alluvial sequence) up to the stage of periglacial conditions preceding the advance of the Narevian ice sheet (upper part of the sequence), or only during the Narevian Glaciation. We cannot exclude that the accumulation of the river series took place at the beginning of the Nidanian Glaciation, preceding the first invasion of the ice sheet onto the Płock Basin. Thermoluminescence (TL) dating of river sands suggests that the sediment is older than 1000 ka.
PL
Spełniając wieloletnie postulaty badaczy czwartorzędu, Komitet Wykonawczy Międzynarodowej Unii Nauk Geologicznych (IUGS) ratyfikował propozycję Międzynarodowej Komisji Stratygrafii obniżenia dolnej granicy czwartorzędu do dolnej granicy piętra gelas (2,588 Ma), a dolna granica plejstocenu została obniżona do tego samego poziomu. Dotychczasowa dolna granica czwartorzędu i plejstocenu, wyznaczona przez stratotyp Vrica w południowych Włoszech i datowana astronomicznie na 1,806 Ma, została utrzymana, ale jako dolna granica piętra kalabr, czyli piętra drugiego od dołu w zrekonstruowanym oddziale plejstocen. Nowa dolna granica czwartorzędu odzwierciedla moment kluczowych zmian klimatu Ziemi w pobliżu granicy epok paleomagnetycznych Gauss i Matuyama. Punkt krytyczny tych zmian został przekroczony około 2,7 Ma, kiedy nastąpiła drastyczna przebudowa cyrkulacji oceanicznej, spowodowana ostatecznym zamknięciem przesmyku panamskiego oraz zmniejszeniem zasolenia wód powierzchniowych Oceanu Arktycznego. Sprzyjało to utworzeniu stałej pokrywy lodowej w Arktyce, a wywołany tym wzrost albedo doprowadził do dramatycznej i jak dotąd nieodwracalnej ewolucji Ziemi, zdominowanej od tego czasu przez epokę lodową, z wielokrotnymi transgresjami lądolodów na kontynentach półkuli północnej.
EN
Many years’ consequent postulates of Quaternary scientists resulted in a decision of the Executive Committee of the International Union of Geological Sciences (IUGS) to ratify a proposal of the International Commission on Stratigraphy to lower the base of the Quaternary to the lower boundary of the Gelasian stage. Simultaneously, the lower boundary of the Pleistocene has been moved to the same position. The previous lower chronostratigraphic boundary of the Quaternary, represented by the Vrica stratotype in southern Italy, has been hardly recognizable outside the Mediterranean Region and neither biostratigraphic indices nor traces of extreme geological events could be found in this very place. On the other hand, an establishment of the Vrica site as the stratotype for the Neogene/Quaternary boundary (equivalent to the Pliocene/Pleistocene boundary) was a driving force to create the Gelasian as a new and uppermost stage of the Pliocene. The Gelasian filled a hiatus between the upper boundary of the Piacenzian stage at Castell Arquato and the boundary of the so-called Plio-Pleistocene at Vrica. The lower boundary of the Gelasian was defined at 2.588 Ma, close to a boundary of the palaeomagnetic epochs Gauss and Matuyama. The new lower boundary of the Quaternary reflects a principal transformation of the climate on the earth. A critical change occurred at about 2.7 Ma, when a severe reconstruction of the thermohaline circulation took place, caused by a final closure of the Panama Straits and inflow of freshwater to the Arctic Ocean. The latter favoured development of constant ice covers in the Arctic, a higher albedo of which resulted in initiation of the ice ages in the northern hemisphere.
PL
W artykule zaprezentowano analizę procesów formowania się składu chemicznego wód podziemnych poziomu płytkiego plejstocenu w obszarze zlewni Gwdy. Wyniki badań hydrogeochemicznych zostały odniesione do pola hydrodynamicznego płytkich poziomów wodonośnych plejstocenu. Analiza zmienności składu chemicznego wód podziemnych umożliwiła opis procesów formowania składu chemicznego tych wód. Ocenę przestrzennego rozkładu zawartości wybranych jonów [...] na podstawie punktowego rozpoznania poddano procedurze geostatycznej (zastosowano metodyę krigingu). Wyróżnione procesy formowania składu chemicznego wód poziomów płytkiego plejstocenu mają głównie charakter geogeniczny i uwarunkowane są obecnym systemem krążenia wód. Lokalna modyfikacja składu chemicznego (np. wzrost ładunków jonów Ca2+) związana jest głównie z zaburzeniami równowagi siarczanowej oraz podrzędnie, z możliwym wzrostem natężenia procesów mieszania się wód płytszych poziomów plejstoceńskich.
EN
The paper presents the analysis of the formation processes of chemical compsition of the shallow Pleistocene aquifers within the Gwda river catchment. The hydrogeochemical results were referred to the hydrodynamical field of shallow groundwater in study area. The variability analysis of the chemical composition of the groundwaters of the shallow Pleistocene aquifers makes it possible to describe the formation of the chemical composition of groundwaters. Geostatistical method (the method of point krining) was applied to estimate spatial distribution of the selected ions [...] concentrations found in the groundwater of the shallow Pleistocene aquifers. The differentiated formation processes of the chemical composition of the shallow Pleistocene aquifers are mainly of natural geological character and are conditioned by the current groundwater flow system. The loceal modification of chemical composition of groundwater (e.g. increase of calcium ions concentration) is mainly connected with disorder of sulfate equilibrium and to a lesser dagree with the increase of mixed groundwater from the differnet shallow Pleistocene aquifers.
PL
Maksymalny zasięg lądolodu warty na Wysoczyźnie Żelechowskiej sięgał po dolinę dolnego Wieprza. Strefie maksymalnego zasięgu towarzyszą moreny czołowe i zaburzenia glacitektoniczne. Morena czołowa w Hucie Radoryskiej powstała w wyniku spiętrzenia i odkłucia piasków i żwirów wodnolodowcowych przez lądolód zlodowacenia warty. Sytuacja geomorfologiczna otoczenia odsłonięcia oraz wykonane pomiary mezostruktur glacitektonicznych pozwoliły wyróżnić trzy etapy ewolucji czoła lądolodu: fazę postoju, fazę nasunięcia i fazę recesji. Główny kierunek kompresji (z NE na SW) 20–50°, wyznaczony na podstawie mezostruktur, odpowiada kierunkowi nasuwania się lądolodu. Geometryczny układ i rozkład przestrzenny wszystkich mezostruktur dowodzi, że są to struktury drugiego rzędu względem wielkiego odkłucia cylindrycznego w którego obrębie się znajdują. Uzyskane wyniki świadczą o dużej dynamice lądolodu zlodowacenia warty na badanym obszarze.
EN
End moraines and glaciotectonic disturbances occur in the zone of Wartanian Glaciation maximum extent, reaching the Wieprz valley in the Ż̄elechów Upland. The end moraine at Huta Radoryska was formed by décollement and upthrusting of glaciofluvial sands and gravels due to the Wartanian ice-sheet advance. Geomorphological setting of the outcrop vicinity and mesostructural analysis have allowed us to distinguish three stages of glacier-front evolution: stopping stage, advance stage and recession stage. The main compression direction (from NE to SW) of 20–50°, determined from mesostructural data – was the direction of ice movement. Geometrical arrangement and distribution in space of all the mesostructures are related to the giant cylindrical shear inside which they occur. Research results show strong dynamics of the Wartanian ice-sheet in the study area.
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