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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.
EN
The geological setting of the Bug-Pripyat interfluve and the close proximity of the source of the Pripyat River to the well-developed Middle Bug River valley suggest that these rivers may have been connected in the past. Analysis of geological cross-sections around the Polish-Ukraine-Belarus cross-border areas together with study of associated Pleistocene palaeoflora shows that buried alluvial deposits of the proto-Bug and proto-Pripyat clearly represent the Preglacial (MIS 103-23), Podlasian/Turskian-Donian/Brest Interglacial (Cromerian I-II; MIS 21-17) and the Mazovian/Likhvinian/Alexandrian Interglacial (Holsteinian; MIS 11c). Their elevated position in mid-eastern Poland suggests the possibility of accumulation by proto-Bug waters flowing eastwards, which determined the formation and development of the lower-lying proto-Pripyat valley system in northwestern Ukraine at those times. The occurrence of the Ponto-Caspian species Lithoglyphus naticoides (C. Pfeiffer, 1828), Borysthenia naticina (Menke, 1845) and Corbicula fluminalis (O.F. Müller, 1774) in the mollusc assemblages of the Mazovian/Likhvinian/Alexandrian Interglacial implies that the main watershed between the Baltic Sea and the Black Sea drainage basins might have been situated in the northern part of the area studied. Presumably its main part was drained by the waters of the proto-Bug catchment connected with the proto-Pripyat and flowing farther to the east towards the Dnieper River entering the Black Sea.
EN
A new borehole in Rożce (SW Mazovian Lowland) drilled in 2012, combined with a wide variety of research methods (palaeomagnetism, palynological analysis, studies of plant macroremains and textural features of deposits) shed new light on the age and stratigraphic position of the Early Pleistocene deposits, formerly assigned as the Lower Pleistocene. The study focuses on the deposits from 50.7-104.0 m depth, between glacial till of the Nidanian Glaciation (ca. 0.9 Ma) and the Poznań Clays (ca. 5.322 Ma). The deposits situated directly underneath the till (50.7-60.2 m) are related to the Nidanian Glaciation and show a reversed polarity and correlate with the end of the Matuyama Epoch. The deposits from 60.2-104.0 m depth were accumulated during the Early Pliocene, i.e. approximately 5.332-4.6 million years ago. They appear to correlate with the middle part of the Gilbert Palaeomagnetic Epoch and thus they are considerably older than previously thought. The cored section indicates a stratigraphic gap of about 3.5 Ma from the Lower Pliocene to the first advance of the Scandinavian ice sheets into Poland, which are thought to have occurred in the early Middle Pleistocene. The analysed deposits accumulated under variable climatic conditions showing two periods with significant aridity alternated with two periods of increased humidity. Deposits of the arid periods contain no pollen, butaeolian sand quartz grains are found. During periods of more humid climate the area was covered by various types of mixed forest.
4
Content available remote ESR dating of the Donggutuo Palaeolithic site in the Nihewan Basin, northern China
EN
The fluvio-lacustrine sequences in the Nihewan Basin, northern China, provide important terrestrial archives about Palaeolithic settlements and, therefore, about early human occupation in high northern latitude in East Asia. Here we present detailed ESR dating of the Donggutuo Palaeo-lithic site, located in this basin. Four levels A, B, C and E of the Donggutuo archaeological layer yield ESR ages ranging from 1060±129 ka to 1171±132 ka with a mean of 1119±132 ka. The ages are con-sistent with the paleomagnetic data, which show that the Donggutuo Palaeolithic site lies just below the onset of the Jaramillo normal subchron (0.99-1.07 Ma). Furthermore, our results indicate that the reliable ESR dating range of bleached quartz using Ti-Li centre can be effectively extended to 1100 ka and the Ti-Li centre was zeroed before the last deposition, which requires improvement of the understanding of the bleaching mechanism conditions.
EN
TheMizerna site (Polish Western Carpathians) is one of the most important Pliocene palaeobotanic sites in Central Europe. Its fresh-water deposits, laid down in a buried river valley, were studied in detail more than half a century ago in natural exposures and shallow boreholes, prior to partial drowning of the area by an artificial lake. The deposits yielded a very rich macrofossil plant collection elaborated in detail by Szafer (1954) who claimed that they represented a continuous succession of the Pliocene through Early Pleistocene plant communities. First palynological examination of the Mizerna deposits (by Oszast) was made more than half a century ago. Re-evaluation of stratigraphic and palaeoclimatic significance of macrofossil plant remains, along with a reassessment of palaeoenvironmental and sedimentary conditions during formation of the Mizerna fresh-water deposits, is in progress. This may help elucidate the problem whether the Mizerna sediments represent both the Pliocene and Early Pleistocene or, solely, the Pliocene successions.
EN
The sub-Quaternary topography of the western Sandomierz Basin has been compared to variable thicknesses of Quaternary sediments and geomorphology of the area. The lithology and age of the top of Miocene strata have been determined. The Witów Series has been interpreted as a sequence of a braided river that used to flow into the retreating marine basin, forming a fan delta whose age, according to macrofloristic determinations, has been assigned to the Late Miocene. Lower Quaternary gravels cap the remnants of a planated surface situated at 240-250 m a.s.l. The Błonie gravel horizon occurring at a similar altitude was deposited by a river active in Narevian and/or Nidanian glacial stages, and its top underwent reworking during the Sanian-2 stage. Deposits infilling the fossil sub-Carpathian Furrow have been mapped and dated to the Cromerian s.l. interglacial stage. The final alluviation of this segment of the furrow took place during the Sanian-2 stage. Reconstruction of the drainage pattern during the Eopleistocene, South-Polish glaciations, and Masovian inter- glacial stage has been proposed as well.
EN
Analysis of type localities of Pleistocene deposits from mid-eastern Poland (Kozi Grzbiet, Łuków, Biała Podlaska and Wilczyn) and southwestern Belarus (Smolarka and Postolovo) has provided a new view on the age, limits and correlation of the oldest Scandinavian glaciations in the area. Integration of palaeontological data with determination of the Brunhes/Matuyama boundary (780 ka) at Kozi Grzbiet and Smolarka suggests that the first glaciation (Narevian) preceded this boundary and had a slightly smaller extent in SW Belarus than hitherto considered. The second glaciation (Nidanian) occurred slightly above or at this palaeomagnetic boundary. In Poland it is the first South Polish Glaciation, a till of which can be traced as far as the Holy Cross Mts. In SW Belarus it is represented by a till to the south of Brest and Bereza, and connected there with the oldest glaciation.
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