Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 10

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
|
|
tom Vol. 64, no. 1
1--12
EN
A new species of micromorphic articulate brachiopod (Rhynchonellida) Lambdarina jugowiensis sp. nov., from the upper Viséan (Sokolec Beds) of central Sudetes, SW Poland, is described. The studied specimens are calcified, what makes them unique in respect of their state of preservation. The material is represented by a full range of growth stages; from brephic to gerontic. Based on its morphological features and the palaeogeographical distribution of all its known species, two main evolutionary lines are proposed for the genus; the Australian and the European ones. Lambdarina was widely distributed in the equatorial-tropical waters of marginal seas of the Palaeotethys Ocean, mostly during Mississippian time.
EN
The aim of this paper is to summarize the current knowledge about the types of interactions between plants and arthropods and to present their evidences in the Paleozoic fossil record. A new classification of these evidences was proposed based on the function and reaction ofplants. This paper presents also their succession, correlated with phases of herbivore arthropod expansion, and phases of evolution ofplant-arthropod interactions in the Paleozoic.
|
2013
|
tom Vol. 57, No. 3
365--384
EN
In this paper the trace fossil associations and the taphocoenoses from the Upper Visean Paprotnia Beds (Bardo Unit) have been compared. Eleven ichnogenera have been recognized (Zoophycos, Chondrites, Protovirgularia, Lockeia, Palaeophycus, Nereites, Planolites, Altichnus, Paleobuprestis, cf. Thalassinoides and ?daedaloid form). A new ichnospecies Paleobuprestis sudeticus has been defined herein. It is the oldest wood-boring trace fossil observed in macroscale and the first wood-boring trace fossil preserved on the archaeocalamites stems. Based on ichnodiversity and relative abundance of trace fossils in the investigated strata three ichnoassociations have been distinguished: Zoophycos–Chondrites–Palaeophycus, Palaeophycus–Nereites and Paleobuprestis. Vertical succession of both the taphocoenoses and ichnoassociations reflects the different colonization stages of the substrate and is linked to bathymetric changes in the marine basin from offshore to nearshore conditions in warm climate at low latitude. The Paprotnia profile is a unique record of the Asbian–Brigantian transition.
EN
The trace fossil Zoophycos has been first time recognized in the Sudetes within the lower Carboniferous (upper Visean, crenistria Zone) of the Paprotnia Beds in the Bardo Unit. A distinct concentration of Zoophycos occurs in the lower part of the Paprotnia profile, in mudstones interbedded with bentonites, which were most likely deposited between storm wave base and fair weather wave base, in oxygenated water.
EN
This report provides detailed information on the taphocenosis succession from the Paprotnia series exposed in the western part of the Bardo Mts. (West Sudetes) and regarded as a temporal equivalent of the pelagic crenistria Limestone (cd III a, Upper Viséan). Five taphocoenoses have been recognised in the investigated section, which is composed of claystone and mudstone shales, greywackes and subordinately by carbonates. They differ mainly in terms of the relative frequency, size and state of preservation of specimens, and less in terms of their taxonomical composition. Changes in their vertical succession are coincidental with changes in the lithological record. Analyses of their taxonomical composition and various parameters of their paleontological record, reviewed herein, were used to estimate the paleoenvironment. Taphocoenosis I was deposited under low-energy conditions, probably in oxygen-deficient waters below the wave base. Taphocoenosis II was most likely accumulated in the environment located between the storm wave and fair weather wave bases, in oxygenated water. The fossils of assemblage III developed in a turbulent environment of well-oxygenated and relatively high-temperature shallow water. The organisms of taphocoenosis IV reflect renewed settling of the shallow seafloor during a short period of low energy conditions interrupted by the rapid delivery of a large quantity of terrigenic deposits. The uppermost part of the section, composed mainly of greywackes, which contain only the remains of terrestrial plants (taphocoenosis V) may suggest proximity to land. Both the paleontological and lithological features of the Paprotnia series indicate gradual environmental changes from offshore to onshore conditions. Consequently, the Paprotnia series represents the shallower facies equivalent of the pelagic crenistria Limestone, which is widespread in the Kulm facies of Variscan Europe
EN
The paper presents the results of geological and landscape studies in the Wojcieszów area (the Kaczawskie Mountains), which include investigation, inventory, documentation and a fi rst of its kind evaluation of its geotourism objects. This area has high values of the natural environment and a rich geodiversity associated with a complicated geological structure (the Kaczawa unit, the metamorphic Kaczawa Complex). Some of the anthropogenic activities (mining), which have revealed interesting fragments of the geological structure, have also infl uenced the increase of geotourism attractions in this area. The area is one of the best examples of the region in the Sudetes, where economic considerations predominate over the protection of the natural environment. Since the 16th century, the crystalline Wojcieszów limestone was mined in numerous quarries (e.g. Silesia, Gruszka, Połom, and Miłek). In the limestone, intensive karst processes occurred mainly in the Paleogene (numerous caves and speleothems). As a result of economic activity, some of the caves had been permanently destroyed and the former “Połom” nature reserve was liquidated in the late 1970s. Currently, the only nature reserve is the “Góra Miłek in Wojcieszów”. The area around Wojcieszów is rich in numerous quarries, where other construction materials were obtained (e.g. phyllites, greenschists, and metarhyodacites). Since the 12th to 20th centuries, copper ore was also exploited (adits and shafts) in the Żeleźniak massif (east of Wojcieszów in the Radzimowice area). In the 20th century, uranium ore was mined at t Chmielarz Hill adit. Recently, the Cambrian limestones (Połom) and Quaternary deposits (Okrajnik, Stara Kraśnica) have been exploited. Paradoxically, economic activity, which caused destruction of some protected objects, has also enriched the geodiversity of the Wojcieszów region. The results of the evaluation proved the signifififi cant geotouristic potential of the studied area. The most attractive geosites around Wojcieszów demonstrate typical lithologies of the Kaczawa Succession and depict the pre-Variscan geological evolution of the area.
PL
W artykule przedstawiono wyniki badań geologicznych i krajobrazowych rejonu Wojcieszowa (Góry Kaczawskie), które obejmowały inwentaryzację, dokumentację i pierwszą waloryzację jego obiektów geoturystycznych. Obszar ten jest cenny pod względem przyrodniczym oraz charakteryzuje się bogatą georóżnorodnością, związaną ze skomplikowaną budową geologiczną (metamorfi k kaczawski, kompleks kaczawski). Na wzrost walorów geoturystycznych tego obszaru wpłynęły też niektóre działania antropogeniczne (górnictwo), które odsłoniły ciekawe fragmenty budowy geologicznej. Okolice Wojcieszowa stanowią jeden z najlepszych w Sudetach przykładów regionu, w którym względy gospodarcze przeważają nad ochroną przyrody. Już w XVI wieku zaczęto w okolicy wydobywać wapień krystaliczny zwany wojcieszowskim, odsłonięty w licznych kamieniołomach (np. Silesia, Gruszka, Połom, Miłek). W wapieniach krystalicznych miały miejsce intensywne procesy krasowe, które zachodziły głównie w paleogenie (bardzo liczne jaskinie, szata naciekowa). Na skutek działalności gospodarczej część jaskiń została bezpowrotnie zniszczona, a dawny rezerwat przyrody „Góra Połom” został zlikwidowany pod koniec lat 70. Obecnie jedynym rezerwatem jest „Góra Miłek w Wojcieszowie”. W okolicach Wojcieszowa występują liczne łomy, w których pozyskiwano inne surowce budowlane (m.in. fyllity, zieleńce, metaryodacyty). Od XII do XX wieku w masywie Żeleźniaka (na wschód od Wojcieszowa w rejonie Radzimowic) eksploatowano również rudy miedzi (sztolnie i hałdy). W XX wieku poszukiwano rud uranu (sztolnia na Chmielarzu). Współcześnie eksploatowane są kambryjskie wapienie (Połom) oraz osady czwartorzędowe (Okrajnik, Stara Kraśnica). Paradoksalnie, działalność gospodarcza, niszcząc niektóre obiekty chronione, jednocześnie wpłynęła pozytywnie na wzrost georóżnorodności w rejonie Wojcieszowa. Wyniki ewaluacji udowodniły znaczący potencjał geoturystyczny badanego obszaru. Zaproponowano najbardziej atrakcyjne obiekty geoturystyczne okolic Wojcieszowa, przedstawiające litologię dolnej części sukcesji kaczawskiej i ukazujące przedwaryscyjską ewolucję tego obszaru.
EN
The siliciclastic rocks of the Paprotnia Beds from the Bardo Unit (Polish Sudetes) provide abundant and diverse palynological material. The miospore assemblages recovered allow distinction of two miospore biozones. The Tripartites vetustus–Rotaspora fracta (VF) Biozone was recognized in the lower and the middle parts of the section. In its upper part the Cingulizonates capistratus (Cc) Subbiozone, the lower part of the Cingulizonates capistratus–Bellispores nitidus (CN) Biozone was distinguished. These results indicate that the rocks of the Paprotnia section, considered earlier on the basis of biostratigraphic and radiometric data as upper Asbian, should be assigned to the upper Asbian and Brigantian. The location of the Asbian/Brigantian boundary and the possible occurrence of a gap in the Brigantian part of the section are discussed. Palynofacies observations of miospore preservation and frequency provided additional information, which confirm the gradual shallowing of the environment of deposition from offshore to onshore. Thermal maturity assessment of organic matter, based on miospore colour, indicates early mature and mature stages of organic matter thermal alteration.
EN
The Lower Carboniferous Paprotnia beds of the Bardo Structural Unit in the central Sudetes, composed predominantly of mudstones with Upper Viséan fossils, include several bentonite layers. The bentonites, composed mainly of kaolinite, illite/smectite and smectite, with minor amounts of quartz, calcite and iron hydroxides, also contain abundant zircons, the features of which indicate their volcanic derivation. The main population of the zircons yielded a SHRIMP U-Pb age of ~ 334 Ma corresponding with, and numerically constraining, the biostratigraphic data. The field evidence, biostrati- graphic and geochronological results, together with mineralogical data from the bentonites, indicate continental margin-type sedimentation and contemporaneous volcanic (andesitic-rhyolitic) activity in the neighbouring region during the ongoing Variscan orogeny in central Europe in Late Viséan times.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.