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EN
The purpose of this paper is to identify and characterize a fault zone located within poorly indurated Pliocene clastic strata occurring in the southern part of the Orava Basin on the boundary of Outer and Central Western Carpathians, close to the Pieniny Klippen Belt. The Orava Basin is a part of the Orava - Nowy Targ intramontane basin. The fault zones within poorly indurated sediments are usually very complex. If the rocks are well indurated, a fault zone is divided into two parts - the fault gouge and the damage zone (Fossen 2010). The fault gouge is characterized by the slip plane and strong deformations such as fractures or clasts' reorientation. Not all the researchers, however, agree with a general fault zone model described by Fossen (2010). This model is indeed appropriate for strongly lithified rocks. In case of poorly lithified sediments, Rawling & Goodwin (2006) and later Gudmundsson (2011) and Loveless et al. (2011) suggested adding the third, additional zone - the mixed zone. It separates the fault gouge and the damage zone and the presence of the deformation bands and clasts' reorientation are its main features. The mixed zone records the initial deformations of the sediment and stays active for some time even after the lithification (Rawling & Goodwin 2006). Although no displacement of strata can be noticed in the studied exposure, the occurrence of numerous fractured clasts and exposure-scale fissures can be used in the interpretation of a potential fault zone. In order to describe the considered fault's anatomy, the presented research has been concentrated on the identification of three main fault parts occurring within poorly indurated strata: the fault gouge, the mixed zone and the damage zone. The analyzed exposure, whose length and height exceeds 70 and 15 meters, respectively, is located within a natural scarp in the Cichy Stream Valley. The scarp is mostly NNE-SSW to NE-SW oriented. It is dominated by poorly indurated Pliocene muddy to sand-supported paraconglomerates, mainly comprised of mudstone and sandstone clasts and up to 40% of matrix. The thickness of the rocks observed within the exposure reaches about 15 meters. Besides that, in few places, lense-shaped bodies of sandstone were observed. Their thickness is lower than 1 meter. They appear in the lower part of exposure, close to its easternmost side. From the neotectonic point of view, three groups of structures were recognized: clast-scale fractures, deformation bands and exposure-scale fissures. The paraconglomerates are dominated by the fractured clasts. The clasts are cut either by one or two sets of fractures. The planes of these fractures mainly strike NE-SW to NNE-SW. In the western part of the exposure, the measurements were the most consistent, while the eastern part shows a greater dispersion of the data. In both western and easternmost parts of the exposure, some clasts are reoriented. Inclination reaches even 90°. Fractured clasts' investigation have yielded information about the intensity of the deformation within the paraconglomerate. The counts have shown that the prevailing amount of the fractured clasts occurs in the western part of the exposure - even 126 counts per square meter. The average amount of fractures observed in the middle of the scarp is 57 per square meter, whereas in the eastern part approximately 30 fractures per square meterwere be counted. The deformation bands have been observed within the lenses of sandstones, located in the center of the eastern part of the exposure. Moreover, the whole exposure is cut by numerous fissures that either cut across or bypass the clasts. Some of them are open and wide, while other are narrow. The fissures differ between themselves in terms of size. Therefore they were subdivided into three groups: (1) cutting the whole exposure, (2) disappearing towards the top of the exposure, (3) inferior (the smallest) ones. Except for one fissure placed on the west, the first group appears mainly in the center of the eastern part of the scarp. Second group is located in the center of the exposure. The third group, in turn, can be observed mainly in the eastern part of the paraconglomerate. Besides the inferior fissures (3), they mostly strike NNE-SSW, similarly to the fractures in clasts. The fractured clasts' abundance, fissures' presence and clasts' reorientation can be interpreted as the indicators of a potential fault zone. The large amount of fractures in clasts in the westernmost part of the scarp, in combination with first group fissure presence and clasts's reorientation, leads to the conclusion that it may represent the location of the fault gouge. Whether the gouge is relatively narrow, the observed reorientation might belong to the adjacent mixed zone. The mixed zone seems to occur in few places within the scarp. Its presence can be inferred from deformation bands' location and clasts' reorientation. Quite high background of fractures at the level of approximately 50 per square meter and tension fissures' presence within the whole scarp may indicate of the damage zone location. In this case, the damage zone would cover the largest part of the exposure, leaving the rest of it for a fault gouge and the mixed zone. The model of the dominant damage zone also matches another theory, associated with a shear zone. In this case, the fissures observed within the scarp could be interpreted as the Riedel fractures related to left-lateral strike-slip fault occurring in the vicinity of the scarp.
EN
The Adriatic Sea is an epicontinental, closed sea, part of the Mediterranean. It formed in the Late Miocene, and ended structurally during the Pliocene and Quaternary, when most of its sediments were deposited. The larger Pliocene and Quaternary depressions occur mostly by the western coast, where the deposits are several thousand metres thick, and were sourced from the Alps and the Apennines. The east coast is characterised by the large and elongated Dinarides Mts., that have continental drainage extremely close to the shoreline and a very small erosional rate. Consequently, eastern inflows were and are very short, including strongly tidal estuaries that erode only small volumes of mostly carbonate detritus, adjacent to frontal islands or mountains, with restricted depositional areas. The Neretva River deposits make up part of the largest contemporary delta system on the eastern Adriatic coast, and have been analysed in this study using three seismic sections and one exploration well. These deposits are recognized inside the Neretva and Korčula channels, assuming that processes operating during Quaternary glacial phases shifted the delta tens of kilometres to the west in the past on several occasions.
EN
This paper describes sedimentology and palynology of freshwater plant-bearing late Cenozoic (Pliocene sensu lato) deposits drilled at Mizerna, the eastern part of the Nowy Targ Intramontane Depression, West Carpathians, South Poland. Our data were obtained from a newly-analysed 39-m thick succession from the Mizerna-Nowa borehole, containing spores, pollen and freshwater organic-walled algal micro-remains. They shed light on the palaeoenvironmental conditions of the Nowy Targ Intramontane Depression, where the Mizerna palaeolake once formed.
EN
We present the first record of benthic foraminiferal assemblages from 92 samples collected at approx. 3 m resolution in the bottom part of Hole U1341B drilled in the southern Bering Sea during Integrated Ocean Drilling Program (IODP) Expedition 323. Pliocene agglutinated foraminifera are generally rare within highly diatomaceous claystones occurring from the base of the hole at 601.87 m below sea floor (mbsf) to ~320 mbfs. The agglutinated foraminiferal assemblages are strongly dominated by the infaunal genera Eggerella, Karreriella, Martinottiella, and Spirosigmoilina. The calcareous-cemented Eggerella and Martinottiella are canaliculated with pores that are open to the test surface. Tubular agglutinated foraminifera are rare and are only found in isolated samples. The ecological information gained from this assemblage supports other proxy information indicating high levels of organic productivity and severely hypoxic conditions in the Bering Sea deep water during the Pliocene.
5
Content available remote Problem granicy pliocen/plejstocen w słodkowodnych osadach Mizernej na Podhalu
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.
PL
Omówiono wyniki dotychczasowych badań geotechnicznych, analizowanych w związku z budową odcinka centralnego II linii metra w Warszawie. Obiekty tego odcinka są wbudowane w utwory czwartorzędu, a w swej dolnej części w utwory trzeciorzędu (pliocenu). Zwrócono uwagę na wpływ wbudowanych w utwory pliocenu konstrukcji obiektów na deformację strumienia wód podziemnych.
EN
Current results of geotchnical research were discussed, analysed in connection with the construction of the central section of the second line of the underground in Warsaw. Object of this section were built in the quaternary formation, and in it's lower part were built in the tertiary formation (pliocene). Attention was drawn to the influence of floor deformation pliocene formations on construction of the underground objects.
EN
The Penguin Island volcano is located on the southern shelf of King George Island (South Shetland Islands, West Antarctica). Its activity is regarded as connected with the opening of the Bransfield Strait. Penguin Island is dominated by a 180 m high basaltic stratocone (Deacon Peak) with a 350 m wide crater containing a small basaltic plug inside and radial dykes, and it has a second principal vent – the Petrel Crater maar – that was formed during a phreatomagmatic eruption about 100 years ago. A low-potassium, calc-alkaline sequence of basaltic lava flows with intercalations of beach deposits (Marr Point Formation) forms the basement of the stratocone. The Marr Point Formation lava flows have never been dated before. Combined whole rock 40Ar-39Ar isotopic dating and magnetostratigraphy were applied for this purpose. We obtained an isotopic 40Ar-39Ar plateau age of 2.7 š0.2 Ma, and together with the palaeomagnetic data, middle Pliocene age (Piacenzian) is implied for the basaltic plateau of Penguin Island.
EN
The paper presents the detailed plate tectonic, paleogeographic, paleoenvironment and plaeolithofacies maps for seven Cenozoic time intervals. Thirty five maps, generated using PLATES and PALEOMAP programs, contain information about plate tectonics, paleoenvironment, and paleolithofacies during Paleocene, Eocene, Oligocene, Miocene and Pliocene, time slices. The spatial reconstruction of basin architectures during their origin, expansion, closure and inversion as well as the dynamic of intrabasinal ridges were obtained by palinspastic modeling. This modeling utilized paleomagnetic data and stratigraphic-facies analysis of basins and ridges. Information contained within global and regional papers were selected and posted on the maps. The detailed paleoenvironment and plaeolithofacies zones were distinguished within the basins. The paleogeographic maps illustrate the geodynamic evolution of Earth from Late Cretaceous to Neogene, spreading and origin of new oceans, oceans closing, collisions, continents accretion and origin of new supercontinents.
PL
Artykuł przedstawia szczegółowe mapy paleogeograficzne dla siedmiu przedziałów czasowych w obrębie kenozoiku. Trzydzieści pięć map, skonstruowanych przy użyciu programów PLATES i PALEOMAP, zawiera informacje dotyczące tektoniki płyt, paleośrodowiska i paleolitofacji w czasie paleocenu, eocenu, oligocenu, miocenu i pliocenu. Przestrzenną rekonstrukcję architektury basenów w okresie ich powstawania, ekspansji, zamykania i inwersji oraz analizę dynamiki grzbietów śródbasenowych uzyskano, wykonując modelowanie palinspastyczne, przy uwzględnieniu badań paleomagnetycznych oraz analizy stratygraficzno-facjalnej basenów i rozdzielających je grzbietów. Informacje zawarte w szeregu globalnych i regionalnych prac zostały wyselekcjonowane i naniesione na mapy. W obrębie basenów wydzielono poszczególne strefy paleośrodowiskowe i paleolitofacjalne. Mapy paleogeograficzne ilustrują geodynamiczną ewolucję Ziemi od późnej kredy po neogen, rozrost (spreding) i tworzenie się oceanów, zamykanie się oceanów, kolizje, łączenie się kontynentów i tworzenie się nowych superkontynentów.
EN
In the eastern Loess Plateau region of Northern China, the Quaternary loess-palaeosol se quences of the last 2.6 Ma are underlain by the Hipparion Red-Earth Formation (namely the "Red Clay"). The red clay is also a significant deposit in Hungary, the origin of which is controversial. This paper is a comparative study of the Central European (Hungarian) red clay succession and the Xifeng Red Clay profile, the type section for this deposits in the eastern Loess Plateau region. Optical microscopic and SEM analysis were used for grain-size measurements, and both major- and trace-element geochemical properties were analysed to ad dress the question of the origin of Hungarian red clay as well as its environmental implication. We compare the Xifeng Upper Red-Earth (age: ~3.6 to 2.6 Ma BP) with the Hungarian, Tengelic Red Clay Formation (age: ~3.5 to 1.0 Ma BP); both are aeolian deposits ~ genetically related to the Quaternary loess -palaeosol sequence.
10
EN
Novocrania turbinata (POLI, 1795) is documented from the Early Pliocene strata of Santa Maria Island (Azores, Portugal), extending the range of this species to the central Northern Atlantic Ocean. This record increases the meagre brachiopod fauna known from the Pliocene of the Azores, which so far consisted only of Terebratulina retusa (LINNAEUS, 1758). It may also represent an example of a thermophilic species that disappeared locally due to Late Pliocene-Pleistocene climate deterioration.
EN
A holoplanktonic mollusc assemblage from Neogene sediments of the Azorean island Santa Maria is described and analysed to determine the age of the sediments. Sixteen taxa are documented (three heteropods, thirteen pteropods), fourteen of which are new records for the fossil fauna of Santa Maria Island. The composition of the heteropod and pteropod assemblage indicates a Zanclean age, which contrasts with earlier age assignments to the Early, Middle or Late Miocene based on benthic molluscs, but is in good agreement with more recent data based on foraminiferal and geochemical evidence. The pteropod Cavolinia marginata (BRONN, 1862) is re-described based on abundant topotypic material and a neotype is designated. The species Cavolinia vendryesiana (GUPPY, 1873) is considered to be a junior subjective synonym of C. marginata. The temporal range of the pteropod Limacina trochiformis (D.ORBIGNY, 1836) is extended to the Zanclean.
12
Content available remote Geologiczno-inżynierskie zachowanie się iłów londyńskich i warszawskich
PL
W pracy przedstawiono ilościową ocenę zachowania się eoceńskich iłów londyńskich i plioceńskich iłów warszawskich jako podłoża gruntowego obiektów budowlanych. Główna uwaga została skoncentrowana na właściwościach fizyczno-mechanicznych tych iłów, a zwłaszcza ich podatności na czynniki egzogeniczne i na działanie obciążeń. Ustalono wielkość zmian parametrów wytrzymałościowych wskutek wietrzenia. Określono również zależność naprężenie-odkształcenie, wytrzymałość maksymalną i rezydualną dla analizowanych gruntów. Porównano iły warszawskie z iłami londyńskimi - te ostatnie należą do najbardziej znanych i zbadanych gruntów na świecie.
EN
A qualitative evaluation of the behaviour of Eocene London Clays and Pliocene Warsaw Clays as a foundation for engineering work is presented, with special emphasis on their physico-mechanical properties - in particular their susceptibility to exogenic factors and loading. The magnitude of changes in strength parameters due to weathering has been defined together with the strain-stress relationships and peak and residual strength of the soils examined. The Warsaw Clays have been compared with London Clays, the latter representing one of the world’s most-studied engineering materials.
PL
W południowo-wschodniej części Niziny Śląskiej w międzyrzeczu Nysy Kłodzkiej i Odry występuje zwarty kompleks neogeńskich osadów rzecznych formacji Gozdnicy. Badania osadów tej formacji prowadzono na stanowisku Tułowice na Równinie Niemodlińskiej. Analiza minerałów ciężkich wykazała, że osady dolnej części profilu, o całkowitej miąższości 18 m, najprawdopodobniej są związane z Nysą Kłodzką, natomiast górnej — z Odrą. Szczegółowym badaniom sedymentologicznym poddano odsłaniające się w wyrobisku osady górnej części profilu. Wyróżniono cztery kompleksy osadów. Na podstawie analizy litofacjalnej stwierdzono, że trzy pierwsze kompleksy powstawały głównie w systemie rzeki meandrującej. Osady kompleksu 4 reprezentują natomiast rzekę o układzie anastomozującym. Próbki z mułowo-ilastych warstw kompleksu 1 i 2 poddano analizie paleobotanicznej. Wynikająca z niej zmienność szaty roślinnej wykazała tendencję do zmian krótkookresowych oscylacji średnich temperatur i wilgotności. Na podstawie badań spektrów pyłkowych stwierdzono plioceński wiek osadów. Transformacja układu koryta, wynikająca z analizy sukcesji osadowej, mogła mieć związek z coraz większymi zmianami klimatycznymi późnego pliocenu, bezpośrednio poprzedzającymi ochłodzenie z początku plejstocenu.
EN
Neogene fluvial deposits of the Gozdnica Formation constitute a continuous cover in the southeastern part of the Silesian Lowland, in the Nysa Kłodzka and Odra interfluve. The 18 m thick succession of these deposits was studied in the Tułowice site on the Niemodlin Plain. Heavy mineral analysis indicates that deposits of the lower part of the succession were probably accumulated by the Nysa Kłodzka River, and those of the upper part — by the Odra River. Detailed sedimentological research was conducted in an excavation where the latter deposits are exposed. Four lithologic complexes were distinguished. It was found that three older complexes were formed mostly ha a meandering river system. The deposits of complex 4 represent alluvium of an anastomozing river system. Palaeobotanical analyses were made for silty-clayey deposits of complexes 1 and 2, and revealed plant cover variability indicating a climatic tendency for short-term oscillations of mean temperatures and humidity. Pollen spectra evidenced Pliocene age of the deposits under study. Both sedimentological and paleobotanical data indicate that the change of fluvial environment could have been associated with a progressive climatic change during the Late Pliocene, directly preceding the Early Pleistocene cooling.
14
Content available remote Karst genesis of the Swabian Alb, south Germany, since the Pliocene
EN
An integrated approach of geomorphological, speleological, climatological and stratigraphical analysis was applied in a selectet study area in the Swabian Alb (south Germany) to determine the spatial and temporal development of deep karstification since the Pliocene. By correlating the field data derived from applying different analysis, four karstification levels could be identified and assigned to the regional landscape development. The oldest and highest level L IV represents only scattered relics of Late Tertiary karstification. Levels L II and L III are clearly determined by terraces and cave levels. They correspond to major stagnation phases of the regional base level of the river Danube and the pre-alpine glaciation in the Late and Middle Pleistocene. The lowest level L I evolved during the major glaciation of the Riss-period and is still active in the upper reaches but buried under younger deposits in the lower reaches of the area. The study points out the necessity of using different methods to characterise the evolution of karstification.
15
Content available remote Geodynamika i neotektonika polskich Karpat zewnętrznych
PL
Polskie Karpaty zewnętrzne reprezentują pasmo fałdowo-nasuwcze, zbudowane z płaszczowin nasuniętych ostatecznie na siebie w środkowym i późnym miocenie. Neotektoniczna (plioceńsko-czwartorzędowa) aktywność tego obszaru przejawiała się w: deformacjach plioceńskich i wczesnoczwartorzędowych powierzchni częściowego zrównania, spaczeniu i pochyleniu cokołów skalnych czwartorzędowych teras rzecznych, zróżnicowanym tempie rozcinania cokołów skalnych jednowiekowych teras rzecznych w obrębie różnych jednostek fizjograficznych, wzmożonej akumulacji w obniżanych zapadliskach śródgórskich oraz zachodniej części zapadliska przedkarpackiego, powstaniu nielicznych czwartorzędowych uskoków normalnych w osadach stokowych i rzecznych, jak również umiarkowaną sejsmicznością w południowej części badanego obszaru. Strefy wykazujące tendencje wypiętrzające są stosunkowo wąskie, a układają się subrównolegle do czół głównych nasunięć i złuskowanych fałdów. Kulisowy układ tych stref, nieco odmienny w zachodniej i wschodniej części Karpat zewnętrznych zdaje się sugerować obecność młodych ruchów lewoprzesuwczych wzdłuż strefy uskokowej Kraków–Lubliniec w podłożu nasuniętych płaszczowin karpackich.
EN
The Polish Outer Carpathians represent a fold-and-thrust belt, composed of a stack of nappes that were finally emplaced during the middle-late Miocene times. The neotectonic (Pliocene-Quaternary) activity of this area is evidenced by: deformed ero-sional surfaces of Pliocene and early Quaternaiy age, upwarped/downwarped/tilted strath and complex-response Quaternary terraces, drainage pattern changes, diversified rates of fluvial downcutting in different units during the same time-span, increased accumulation in subsiding intramontane basins and in the westernmost part of the Carpathian Foredeep, few examples of Late Quaternary faulting of fluvial and slope sediments, young jointing within Pliocene molasses in intramontane basins and those of early Quaternaiy age in the Carpathian foredeep, as well as by historical records of minor seismicity, usually confined to the Pieniny Klippen Belt and some oblique-slip faults that cut the inner parts of the Outer Carpathians, of magnitudes not exceeding 5.0 on the Richter scale. The zones showing tendencies to Recent uplift tend to be aligned subparallel to frontal thrusts of individual nappes and larger slices, suggesting the presence of Plio-Quaternary horizontal stresses in the flysch nappes. En echelon arrangement of theses zones, however, slightly different in the western and eastern parts of the study area appears to indicate young sinistral motions along the Kraków-Lubliniec fault in the substratum of the overthrust nappes.
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