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EN
Petrographic studies covered 20-60 mm coarse gravel and 4-10 mm medium-grained fractions of two till horizons (units ŁS II and ŁS IV) and two beds of sand-gravelly-outwash deposits(units ŁS I and ŁS III) associated with the Odra Glaciation (MIS6) in Łubienica-Superunki on the North Mazovian Lowland. Regardless of the facies type and grain sise, crystalline rocks dominate over all other petrographic groups in all samples. The percentage of crystalline rocks is greater among coarse gravel (average 74.7%) than among medium-grain gravel (average 67.8%). The share of carbonate rocks is limited only to the both lower units ŁS I and ŁS II. The upper units (ŁS III and ŁS IV) are deprived of these rocks, both in the medium and coarse gravel fraction. Sandstones, presented in all samples, were in the range of 5-20%. From the other petrographic groups, individual chalk limestones clasts, dolomites, flints and quartz grains were identified in the material. The indicator erratics were identified in all four units. Their percentage content stands for 10-18% of the total sample of coarse-grained fraction. Among them, the most common were the erratics derived from the Åland Islands, and then from the area of south-eastern Sweden (Smaland) and from Dalarna in central Sweden. Amongst the erratics with limited indicator significance, Lower Paleozoic limestones and Jotnian sandstones were most frequent. Single fragments of Ordovician red and Paleoporella limestone were present. These rocks, including the Lower Paleozoic grey limestone, occurred only in thelowerunits(ŁS I and ŁS II). The results of the research suggest that the two lower sediment units should be correlated with a ice-sheet advance (Middle Polish Complex, Odranian Stadial?), and the two upper ones - with a separate, subsequent advancement (Wartanian?). The paper is another methodological contribution to the consideration of abandoning the tedious testing of glacial till and focusing on a much faster petrographic analysis of fluvioglacial sediments associated with the same ice sheet. This is demonstrated by the comparable results of the petrographic analysis of short transport outwash sediments and till from a single glacial period.
EN
The Upper Odra Lobe - the southernmost part of the Scandinavian ice sheet during the Odranian (Drenthe) glaciation - was formed in the area of the Niemodlin Plain and the western part of the Racibórz Basin. It created a complex structure consisting of several sublobes: Odra, Nysa, Ruda and Klodnica sublobes. The study focused on the basal till deposited during ice sheet advance. Ice flow directions and the general pattern ofice mass distribution in the Upper Odra Lobe were defined based on the clast fabric. The resulting distribution of ice-flow palaeodirections suggest that the Upper Odra Lobe was formed by the mass of ice moving divergently from the Opole Plain located to the north of the Racibórz Basin. Ice-flow lines coincide with the pattern of major geomorphological units. The most intensive movement of the ice took place in the depression of the central part of the Silesian Lowland. From there, in the vicinity of the Niemodlin Plain, the ice sheet moved in different directions, forming smaller sublobes in several valleys. Strong relationship between the ice flow directions and morphology confirms the idea of a smaller ice sheet extent in the Racibórz Basin and Moravian Gate. Highly concentrated flow of ice in the back-lobe area, interpreted in this study, suggests that the lobe development resulted not only from the ice sheet adapting to the basement relief, but was also conditioned by a spatially varying distribution of ice, i.e. increased ice supply to the Niemodlin Plain and the western part ofthe Racibórz Basin.
EN
During the Pleistocene, the Cracow-Częstochowa Upland was covered by the Scandinavian ice sheets two times, which was stated already at the beginning of the twentieth century. The Odra glaciation had probably the biggest impact on the relief of this area . The geometry of this part of the ice sheet was reconstructed on the basis of the analysis of the sub-Quaternary morphology and location of the glacial tills. The modeling of thickness of the ice sheet during the odra glaciations shows, that it was small (110–350 m) in the northern part of the analyzed area. Longitudinal profiles of the ice sheet are fairly gentle, which is typical for glaciers with high activity.
PL
Przedmiotem artykułu jest analiza strukturalno-kinematyczna kompleksu deformacji glacitektonicznych, wyodrębniającego się jako osobne piętro strukturalne w strefie rowu Kleczewa (elewacja konińska). Analiza makrostrukturalna pozwoliła zdefiniować trzy podjednostki strukturalne A, B i C. Analiza strukturalno-kinematyczna mezostruktur wykazała znaczące różnice w rozwoju strukturalnym poszczególnych podjednostek. Podjednostkę strukturalną A reprezentują głównie fałdy i nasunięcia, rozwijające się w polu kompresji horyzontalnej przed czołem nasuwającego się lądolodu zlodowacenia Odry. Deformacjom podlegały głównie osady starsze od zlodowacenia Odry, tj. iły formacji poznańskiej miocenu górnego, węgle brunatne formacji poznańskiej miocenu środkowego a podrzędnie gliny T1 zlodowacenia południowopolskiego. Niewielki udział w deformacjach miały dolne partie serii glacifluwialnej z Jóźwina z fazy anaglacjalnej zlodowacenia Odry. Podjednostka strukturalna B obejmuje wyższe partie serii glacifluwialnej z Jóźwina, które przykrywają, a miejscami rozcinają erozyjnie, struktury podjednostki A. Osady podjednostki B są pocięte uskokami normalnymi powstałymi w efekcie pionowych przemieszczeń podścielających je struktur podjednostki A. Podjednostka strukturalna C jest reprezentowana głównie przez struktury wskazujące na ścinanie proste w płaszczyźnie (sub)horyzontalnej w warunkach subglacjalnych. Obejmuje ona glinę T2 zlodowacenia Odry oraz strefy kontaktu z podłożem. Pod względem mezostrukturalnym glina T2 reprezentuje melanż typu block in matrix. Podrzędną rolę w rozwoju strukturalnym podjednostki C odgrywała ekstensja horyzontalna w efekcie aktywizacji makrostruktur podłoża w trakcie rozpadu lądolodu zlodowacenia Odry.
EN
The complex of glaciotectonic deformations within Kleczew graben zone (Konin Elevation) is the object of present study. The analysis of macrostructures was the basis for definition of three structural sub-units A, B and C. Mesostructures were studied in detail within each of these sub-units. The structural sub-unit A is mainly represented by folds and thrusts produced by horizontal compression in front of advanced Odranian ice-sheet. These structures developed mainly within the Upper Miocene Poznań Formation clays, the Middle Miocene Poznań Formation brown coals and the South Polish glacial tills. The structural sub-unit B is composed of the glaciofluvial series from Jóźwin of the Odranian Glaciation, which cover discordantly deformed sediments of the sub-unit A. The sediments of the sub-unit B are dissected by lot of normal faults and high angle reverse faults. These structures were produced by horizontal extension related to vertical uplift of structures of sub-unit A. The structural sub-unit C is represented mainly by glacial till T2 of the Odranian Glaciation and contact zone between this till and the older sediments. The style of deformation of these sediments shows (sub)horizontal simple shearing under subglacial conditions. Within the complex of glaciotectonic deformations, the horizontal extension was the youngest deformation event produced by vertical uplift of the basement during decaying of the Odranian ice-sheet.
EN
The Orłowo Cliff is built of glacial and fluvioglacial deposits, Middle Polish Glaciations (possibly Odranian and Warthanian) and Vistulian Glaciation. Deposits are heavily deformed glaciotectonically. In the northern part of the cliff, Miocene sediments are exposed. It is possible, that the Miocene sediments were dislo-cated from their primary position. There were observed overthrusts and intermingling with Pleistocene material in the lower part of the exposure. The Orłowo Headland is built of glacial tills. It is probably a part of fold, similar in pattern to the structure of overthrust folds present in silty-sandy-grained deposits in the southern part of the cliff. Apart from folds and overthrusts there are many faults and the boudinage. Structural analysis of glaciotectonic deformations in conjunction with origin of deposits and statigraphic research enabled the recognition of several stages of development of deformations. Two local directions of glaciotectonic transport were marked clearly: from the north-east, which was connected with glacier invasion in the OEwiecie Stadial of the Vistulian Glaciation, and direction from north-west (north north-west), related to the Main Stadial of the Vistulian Glaciation.
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