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Zasady klasyfikacji stratygraficznej czwartorzędu Polski i jej główne kategorie

Marks Leszek

Przegląd Geologiczny

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2023

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Vol. 71, nr 10

485--502

EN

A reliable stratigraphic subdivision of the Quaternary is extremely important, dependent firstly on primary significance of its deposits in geological investigations and every-day life of human societies. In the Cenozoic, the Quaternary is a period of the same stratigraphic rank as the Palaeogene and the Neogene, but it is much shorter. Traditional stratigraphic schemes of the Quaternary were based mostly on other criteria than of the older periods, because studies of the Quaternary were focused mainly on more easily accessible terrestrial deposits and a decisive role in their formation was played by climate-induced processes. These factors forced a specific approach to define the stratigraphic units and to create the stratigraphic subdivisions of the Quaternary. In the Quaternary investigations in Poland, several categories of stratigraphic classification are used, particularly lithostratigraphy (with pedostratigraphy and cryostratigraphy), morphostratigraphy, biostratigraphy (including palynostratigraphy, malacostratigraphy, teriostratigraphy and anthropostratigraphy), magnetostratigraphy, chronostratigraphy (synchronized with geochronology) and climatostratigraphy (combined with oxygen isotope stratigraphy). The main climatostratigraphic units can be treated as corresponding to the chronostratigraphic ones and it enables correlation in a regional and global scale. Acritical overview of the applied stratigraphic categories and the updated stratigraphic subdivision are presented for Poland.

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Aalenian (Jurassic) to Berriasian (Cretaceous) chronostratigraphic zonation and guide ammonites of the Central Andes (Argentina, Chile, Peru)

Parent Horacio

Volumina Jurassica

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2022

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Vol. 20

1--46

EN

In the Central Andes there are developed two marine basins with an extensive Jurassic record: the Neuquén (or Central Andean) Basin and the Tarapacá Basin. Their Jurassic and Lower Cretaceous ammonite successions have been studied extensively for more than 150 years, producing detailed chronostratigraphic scales based on ammonite zones and biohorizons. The ammonite faunas include Andean lineages, and cosmopolitan, Tethyan, Caribbean, North American, and Indo-Madagascan elements. This paper presents the results of a revision of the zonation of the interval Aalenian-Berriasian. Before presenting the results, this paper emphasizes the distinction between, and the convenient nomenclature for, biozones, zones, standard zones, and biohorizons. The scissum Hz. (new) is introduced in the lower (-most?) Manflasensis Zone (Aalenian). The Rotundum Subzone (new) with base at the cf.-leptus Hz., is introduced for the upper part of the Rotundum Zone (Bajocian). The Gulisanoi Zone (Bathonian) is standardized by designation of the cf.-aspidoides Hz. (new) as its base. The Chacaymelehuensis Zone (new) with base at the “prahecquense” Hz. (new) is introduced for the Callovian. The Cubanensis Zone (Oxfordian) is introduced to replace nominally, or to rename, the inconveniently named “Passendorferia” Zone. The Tarapacaense Zone (Oxfordian) is standardized by designation of the tarapacaense Hz. (new) as its base. The Tithonian Malarguensis Zone (formerly subzone) is here emended and standardized by designation of the malarguensis Hz. as its base; this zone replaces the unviable Mendozanus Zone. The Zitteli Zone is standardized by designation of the widely recorded perlaevis Hz. as its base. The Fascipartita Subzone (Internispinosum Zone) is standardized by designation of the internispinosum-beta Hz. (new) as its base. The Alternans Zone is standardized by designation of the vetustum Hz. as its base, and the Koeneni Zone (uppermost Tithonian) by designation of the striolatus Hz. as its base.

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Late Glacial palaeoenvironmental changes in the southern part of the Holy Cross Mountains based on the "Białe Ługi" peatland record

Okupny Daniel, Malkiewicz Małgorzata, Pawłowski Dominik, Ludwikowska-Kędzia Małgorzata, Borówka Ryszard Krzysztof, Forysiak Jacek, Michczyński Adam, Jucha Witold, Cybul Piotr, Żurek Sławomir

Studia Quaternaria

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2019

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Vol. 36, Nr 2

119--135

EN

This paper presents the Late Glacial stage of the development of the Białe Ługi peatland in the southern Holy Cross Mountains, based on a comprehensive palaeoenvironmental data. A complex analysis of palynology, Cladocera, sedimentology, geochemistry and 14C dating were used. Organic deposition was initiated during the Oldest Dryas. The sedimentary record of the aquatic and terrestrial ecosystems reflects considerable difference between cooler (Oldest, Older and Younger Dryas) and warmer phases (Bølling and Allerød). Periods of intensified interaction between Aeolian processes and peatland are related to stages of disappearing vegetation and changes in aquatic invertebrate communities. We therefore suggest that peatlands were created as a result of local lithological-structural, tectonic, hydrogeological and morphological conditions, and the peatland development rate was largely influenced by changing climatic conditions, which determined local vegetation development, intensity of denudation processes and water level changes. The results validate significance of selection and use of several methods, as well as value of biogenic deposits from the Białe Ługi peatland as archives of past climate change in the Małopolska Upland. Relatively stable water conditions and uninterrupted biogenic sedimentation in the Late Glacial that were provided by the geological structure and relief suggest the studied peatland is a leading one in the region.

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Tithonian stratigraphy and ammonite fauna of the Vaca Muerta Formation in Mallín Quemado (Neuquén Basin, Argentina), with remarks on the Andean chronostratigraphy

Garrido A. C., Parent H, Brambilla L.

Volumina Jurassica

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2018

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Vol. 16, no 1

1--26

EN

In the Cerro Mallín Quemado area (Sierra de la Vaca Muerta) the three members of the Vaca Muerta Formation (Portada Covunco, Los Catutos and Pichi Moncol) can be recognized, including the whole of the Tithonian rock-record. The ammonite fauna does not show significant differences with respect to that of the nearby locality Pampa Tril, but the record of faunal horizons is patchier. Eighteen species of ammonites were recorded through the studied sections, covering the whole of the Andean Tithonian. The current chronostratigraphic zonation of the Andean Tithonian is briefly discussed, updated and correlated with the most recent literature. From the current succession of ammonite bio-horizons previously defined in the basin, only three (picunleufuense alpha, picunleufuense beta and falculatum) were recognized definitely. Four other bio-horizons (perlaevis, erinoides, internispinosum alpha and vetustum) were recognized only tentatively, because the typical assemblages of morphotypes (morpho-species) were not clearly or completely recognized. The current regional time-correlation chart dated by the ammonite bio-horizons of the Neuquén Basin along a 70°W transect is updated with the results of the present study and additional information recently obtained from other localities

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Early Holocene alluvia in the lower Wisłok River valley and their chronostratigraphy in the light of radiocarbon datings and palynological analysis

Superson S., Gębica P., Michczyński A., Kołaczek P., Szczepanek K.

Geochronometria

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2017

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Vol. 44, no. 1

216--225

EN

The paper presents the results of the latest radiocarbon dating and the palynological analyses of organic sediments found in the alluvia of the Wisłok River valley between the towns of Łańcut and Przeworsk. The study conducted in the gravel pit made possible the dating of several alluvial fills of the 7–8 m high Holocene terrace and the 5–6 m high floodplain. The oldest channel alluvia and palaeochannel sediments of the 7–8 m high terrace were dated at 10 100–9300 BP (11 960–10 500 cal BP). According to the anthracological analysis the top cover of clay overbank alluvia, which bears charcoal fragments, was deposited in the Subboreal and/or the Subatlantic Phases. In the sequence of the 5–6 m high floodplain, the bottom fills of palaeochannels, dated at 10 195–9885 cal BP (probability level: 68.2%; GdS-3233: 8900 ± 95 BP ) and 11 095–10 755 cal BP (probability level: 68.2%; GdS-3228: 9575 ± 95 BP), were truncated by erosion and covered by alluvia of palaeomeanders, which were active in the 19th century. Preservation of the erosional bench of the Early Holocene organic sediments indicates the predomination of lateral migration of the river channel during the last 200 years and the formation of wide erosional floodplain that has been aggraded with recent flood alluvia. In the 20th century the floodplain aggradation was simultaneous with the deepening of the Wisłok riverbed.

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Integrated biostratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland

Walaszczyk I., Dubicka Z., Olszewska-Nejbert D., Remin Z.

Acta Geologica Polonica

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2016

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Vol. 66, no. 3

313--350

EN

The biostratigraphic importance, current zonations, and potential for the recognition of the standard chronostratigraphic boundaries of five palaeontological groups (benthic foraminifers, ammonites, belemnites, inoceramid bivalves and echinoids), critical for the stratigraphy of the Santonian through Maastrichtian (Upper Cretaceous) of extra-Carpathian Poland, are presented and discussed. The summary is based on recent studies in selected sections of southern Poland (Nida Synclinorium; Puławy Trough including the Middle Vistula River composite section; and Mielnik and Kornica sections of south-eastern Mazury-Podlasie Homocline) and of western Ukraine (Dubivtsi). The new zonation based on benthic forams is presented for the entire interval studied. Zonations for ammonites, belemnites and inoceramid bivalves are compiled. All stage boundaries, as currently defined or understood, may easily be constrained or precisely located with the groups discussed: the base of the Santonian with the First Occurrence (FO) of the inoceramid Cladoceramus undulatoplicatus; the base of the Campanian with the Last Occurrence (LO) of the crinoid Marsupites testudinarius and approximated by the range of the foraminifer Stensioeina pommerana; and the base of the Maastrichtian approximated by the FO of the inoceramid bivalve Endocostea typica and the FO of the belemnite Belemnella vistulensis. The positions of substage boundaries, as currently understood, are constrained in terms of the groups discussed.

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Sedimentological interpretation and stratigraphical position of glacigenic deposits in the Napęków area (Holy Cross Mountains, Poland)

Ludwikowska-Kędzia M., Pawelec H., Adamiec G.

Geologos

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2015

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Vol. 21, No. 4

261--284

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).

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U-Pb zircon age of the Krásné Loučky tuffite : the dating of Visean flysch in the Moravo-Silesian Paleozoic Basin (Rhenohercynian Zone, Czech Republic)

Jirásek J., Wlosok J., Sivek M., Matýsek D., Schmitz M., Sýkorová I., Vašíèek Z.

Geological Quarterly

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2014

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Vol. 58, No. 4

659–-672

EN

The only previous U-Pb zircon date for the the Early Carboniferous flysch sequence of the Moravo-Silesian Paleozoic Basin was published in 1987 from tuffogenic material from Kobylí Quarry at Krásné Loučky near the town of Krnov (Silesia, Czech Republic). The measured age of 319 Ma did not agree with its stratigraphic position, and was used as the basis for a hypothesized block of Late Carboniferous paralic molasse incorporated during a later tectonic event. During a survey of the still active quarry in 2010, volcaniclastic horizons were identified and sampled. Direct correspondence of the tuff units to those sampled in 1987 cannot be proved but is likely. High precision chemical abrasion - thermal ionization mass spectrometry (CA-TIMS) U-Pb dating of zircon from this new material has yielded an age of 340.05 ± 0.22 Ma, which correlates to the previously inferred stratigraphic age of the locality and the current calibration of the Early Carboniferous geologic time scale. The newly established age corresponds to the Visean stage and dates the boundary between the Horní Benešov and Moravice formations that can be correlated with other foredeep basins of the Culm in the European Variscides. A population of detrital Cambro-Ordovician zircons and a single 2.0 Ga old zircon crystal from the same volcaniclastic layer dated by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) are consistent with the known age of source material in the Variscan orogenic front.

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How to resolve Pleistocene stratigraphic problems by different methods? A case study from eastern Poland

Terpiłowski S., Zieliński T., Kusiak J., Pidek I.A., Czubla P., Hrynowiecka A., Godlewska A., Zieliński P., Małek M.

Geological Quarterly

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2014

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Vol. 58, No. 2

235--250

EN

Different methods have been used to determine the stratigraphic position of Pleistocene alluvial deposits, particularly fluvial interglacial deposits. Near-surface deposits of a meandering river, developed in point-bar and oxbow lake facies, in the Samica River valley (near Łuków, eastern Poland) have been investigated. The fossil valley is incised into the till plain and the outwash. The fluvial succession is locally overlain by solifluction deposits. All the deposits underwent sedimentological analysis. The petrographic composition of basal till occurring in the vicinity of a fossil valley was determined with the method of indicator erratics. Fluvial deposits were examined by pollen analysis and plant macrofossil analysis of oxbow lake facies. Absolute dating methods were applied to the deposits (thermoluminescence methods: TL and additionally IRSL). Lithological differences between fluvial and the surrounding glaciofluvial deposits were identified and their lithostratigraphic position assigned. Petrographic analysis of till and palaeobotanical analyses of oxbow lake facies gave compatible results. Fluvial deposits were formed after the Sanian 2/Elsterian Glaciation, during the Mazovian/Holsteinian Interglacial. Luminescence dating of the fluvial deposits by the TLMAX method yielded the most relevant results (412-445 ka), which indicate that these deposits were formed during the end of the MIS 12 and beginning of the MIS 11 stage.

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Chronostratigraphy of alluvia and age of fluvial landforms in the Carpathian Foreland during the Vistulian

Gębica P.

Studia Quaternaria

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2013

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Vol. 30, Nr 1

19--27

EN

A development of opinions on stratigraphy of alluvia and age of the Vistulian terraces in the valleys of the Carpathian foreland is presented, based mainly on publications of Professor Leszek Starkel. Studies of age of fluvial landforms and sediments of the Last Cold Stage in the Carpathian foreland have been started more than 100 years ago. Before them modern sedimentological methods and radiocarbon dating were introduced, pioneer studies of Pleistocene river terraces and sediments in the Carpathians were performed by Mieczysław Klimaszewski, and subsequently, by his student Leszek Starkel who mapped in 1950s a margin of the Carpathian Foothills as well as alluvial fans of Wisłoka, Wisłok and San rivers in the Carpathian foreland. In that time a stratigraphy of alluvial infillings in the marginal mountain zone was elaborated for the Late Vistulian and the Holocene. Starting from 1970s and basing on studies in key sites in the Wisłoka valley near Dębica, focused on palynological analyses and radiocarbon dating, general strati-graphical schemes of alluvial fills within the Vistulian terrace 15 m high and within the Holocene terrace 8-10 m high have been constructed. A comparison with the valleys in a periglacial area prowed that the Vistulian terrace 15 m high was incised before the maximum extension of the last Scandinavian ice sheet (i.e. before 20 ka BP) and the terrace 11-12 m high (with relics of braided river channels) was formed at the decline of the Plenivistulian. A final incision below the present river bed and aggradation occurred during the Late Vistulian (13-10 ka BP). The rivers changed their regime and their channel pattern from braided to large meanders-type as an effect of forest development and lower sediment load. The Younger Dryas cooling resulted in increased bedload and braiding.

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Progress in the Holocene chrono-climatostratigraphy of Polish territory

Starkel L., Michczyńska D. J., Krąpiec M., Margielewski W., Nalepka D., Pazdur A.

Geochronometria

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2013

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Vol. 40, no. 1

1-21

EN

The Holocene delivers a unique possibility to establish climatic stratigraphic boundaries based on detailed chronostratigraphy reflected in various facies of continental sediments, in their lith-ological parameters and organic remains. These sediments are dated by the 14C method in the case of organic remains, by counting annual laminations in lacustrine facies, and by dendrochronological method in the case of fluvial sediments. The existence of well dated profiles enables to reconstruct various climatic parameters like ampli-tudes of seasonal temperatures, types and frequency of extreme rainfalls and floods and, finally, to distinguish rare rapid changes and most frequent gradual ones. This reconstruction is based on the analogous effects of various types of present-day rainfalls. The current authors present a critical review of existing chronostratigraphic divisions starting from simple millennial division by Mangerud based on Scandinavian palynological stratigraphy of peat-bogs and Starkel's concept based on fluctuations in rainfall and runoff regime reflected in fluvial and other facies of continental deposits. In the last decades, the calibration of 14C dates allowed a new approach to be used for the construction of the probability distribution function of these dates in various facies or types of sediments, which formed a background for distinguishing and correlating climatic phases and defining boundaries be-tween them. These approaches have been creating new opportunities for revision of the existing chronostratigraphy. The aim of this paper is to present a revised version of chronostratigraphic division based on climatic fluctuations reflected in various facies of sediments on the territory of Poland and discuss their corre-lation with other European regions and global climatic changes.

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Radiocarbon ages of bones from Vistulian (Weichselian) cave deposits in Poland and their stratigraphy

Lorenc M.

Acta Geologica Polonica

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2013

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Vol. 63, no. 3

399--424

EN

Twenty-six bone samples from cave sediments mainly of Vistulian (Weichselian) age were radiocarbon (AMS) dated. The material comes from seven localities in the Krakow-Czestochowa Upland and in Podhale (southern Poland). These are: the Komarowa Cave, the Deszczowa Cave, the Upper Rock Shelter of the Deszczowa Cave, the cave in Dziadowa Skala, the Saspowska Zachodnia Cave, the Mamutowa Cave and the Oblazowa Cave. The obtained radiocarbon ages of most of the samples differs from their stratigraphy as formerly proposed. The reasons for this discrepancy are discussed. Also examined were the radiocarbon ages of bones from other caves in the study area. Most of the dated bones are shown to have come from relatively short time periods. The existing data on radiocarbon age of bones from Vistulian cave deposits of the Krakow-Czestochowa Upland and Podhale are summarized.

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Lower and Middle Cenomanian ammonites from the Morondava Basin, Madagascar

Kennedy W. J., Walaszczyk I., Gale A. S., Dembicz K., Praszkier T.

Acta Geologica Polonica

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2013

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Vol. 63, no. 4

625--655

EN

Lower and Middle Cenomanian ammonite assemblages have been collected on a bed-by-bed basis from localities at Vohipaly and Mahaboboka, Madagascar, as well as from outcrops around Berekata, all in the Morondava Basin, southwest Madagascar. These collections demonstrate the presence of the upper Lower Cenomanian Mantelliceras dixoni Zone and the lower Middle Cenomanian Cunningtoniceras inerme Zone of the north-western European standard sequence. These records indicate that the striking anomalies in the zonal assemblages of the classic divisions of the Madagascan Cenomanian are based on mixed assemblages, rather than a succession that differs radically from that elsewhere in the world. The dixoni Zone fauna is: Desmoceras cf. latidorsatum (Michelin, 1838), Pachydesmoceras kossmati Matsumoto, 1987, Forbesiceras sp., F. baylissiWright & Kennedy, 1984, F. largilliertianum (d'Orbigny, 1841), Mantelliceras cantianum Spath, 1926a, M. dixoni Spath, 1926b, M. mantelli (J. Sowerby, 1814), M. picteti Hyatt, 1903, M. saxbii (Sharpe, 1857), Sharpeiceras sp., S. falloti (Collignon, 1931), S. mocambiquense (Choffat, 1903), S. cf. florencae Spath, 1925, Acompsoceras renevieri (Sharpe, 1857), A. tenue Collignon, 1964, Calycoceras sp., Mrhiliceras lapparenti (Pervinquičre, 1907), Mariella (Mariella) stolizcai (Collignon, 1964), Hypoturrilites taxyfabreae (Collignon, 1964), Turrilites scheuchzerianus Bosc, 1801, Sciponoceras cucullatum Collignon, 1964, and Sciponoceras antanimangaensis (Collignon, 1964). The presence of Calycoceras in a Lower Cenomanian association represents a precocious appearance of a genus typically Middle and Upper Cenomanian in occurrence, and matches records from Tunisia. The inerme Zone yields a more restricted assemblage: Pachydesmoceras kossmati, Forbesiceras baylissi, Acanthoceras sp. juv., Cunningtoniceras cunningtoni (Sharpe, 1855) and Hypoturrilites taxyfabreae.

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Wydajność złączeń i zagnieżdżeń dla schematów znormalizowanych i zdenormalizowanych

Jajeśnica Ł., Piórkowski A.

Studia Informatica

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2010

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Vol. 31, nr 2A

445-456

PL

Niniejszy artykuł stanowi rozważania na temat wydajnościowych aspektów normalizacji schematów baz danych. Przedstawiono ideę konstrukcji dużych baz danych i hurtowni w postaciach znormalizowanej (schemat płatka śniegu) i zdenormalizowanej (schemat gwiazdy). Jako przykład wybrano wymiar czasu geologicznego, nieodzownego w konstrukcji baz danych geologicznych. Wymiar ten tworzy hierarchię jednostek geochronologicznych. Przeprowadzono eksperymenty sprawdzające wydajność dla złączeń i zagnieżdżeń skorelowanych dla systemów zarządzania bazami danych MySQL i PostgreSQL.

EN

This article provides a reflection on the performance aspects of database normalization schemas. It resents the idea of the construction of large databases and warehouses on standardized forms (snowflake schema) and denormalized (star schema). Dimension was chosen as an example of geological time, indispensable in the construction of geological database. This dimension creates a hierarchy of chronostratigraphy units. Experiments were carried out to check the performance of the joints and nesting correlated to the database management system MySQL and PostgreSQL.

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Pozycja chronostratygraficzna granicy neogen/czwartorzęd

Marks L.

Biuletyn Państwowego Instytutu Geologicznego

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2010

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nr 438

93--97

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.

16

The Jurassic of Germany

Monnig E.

Volumina Jurassica

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2006

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Vol. 4, no. 1

192-193

EN

A geological map of Germany showing the distribution of Jurassic rocks is presented together with an updated and revised lithostratigrahic scheme for the Jurassic succession of this area. Geological map and important outcrops The Jurassic of Northern Germany crops out as a narrow band between the town of Osnabrück and the Harz Mountains. This visible part is only one percent, the other 99 percent lie in the subsurface and have an extension of over 100,000 km2. The Jurassic of Southern Germany is nearly half as large but much better exposed in the Swabian and Franconian Albs with very important fossil localities (Holzmaden, Solnhofen). Other areas are near Trier and in the Rhine Valley between Mannheim and Basel. The main subsurface data came from over 100,000 boreholes or shafts, which have sunk for the extensive exploitation of oil, gas, salt, iron ore, caverns/disposal sites, radioactive waste disposal or water. Borehole measurements, cores and drill cuttings provided an immense quantity of data as well as on about 500,000 km of reflection seismic lines of different quality. Stratigraphic Table The Jurassic lithostratigraphic scheme is based on the Stratigraphic Table of Germany 2002 (Mönning et. al. 2002). Here the Jurassic is represented by two abstracted and schematised cross sections from west to east. In contrast to this several troughs are considered in more detail. The Jurassic of Northern Germany is situated within the North German Depression representing the central part of the Middle European Depression. It is an area of long-term subsidence and sediment accumulation. From the Late Triassic the basin was subdivided into NW to WSW-ESE striking troughs and swells as a result of halokinetic movements. Where salt accumulated, it pushed upwards as diapirs, leading in the Middle Jurassic to widespread erosion. In southern Germany Jurassic deposits are less thick but more constant in facies development. The lithostratigraphic subdivision of the Jurassic deposits of southern Germany into Schwarzer Jura, Brauner Jura and Weißer Jura is undoubtedly fixed since Quenstedt (1843). The Norddeutscher Jura (Northern German Jurassic Super Group) does not exactly correspond to the Jurassic System and extends from the Hettangian to the Lower Berriasian. (Mönnig et al. 2002). Here the terms Lias, Dogger and Malm has been used since a long time as lithostratigrapic units leading to some confusion. For example the Malm-Gruppe (Gramann et al. 1997) does not correspond exactly with the Upper Jurassic Subsystem (Malm). It excludes the upper Ornaten-Ton Fm. (Lower Oxfordian) and includes the upper Münder Fm (Lower Berriasian). It is proposed to enclose the word Norddeutsche to the terms Lias-, Dogger- and Malm-Gruppe to emphasise the lithostratigraphic character. In connection with the revision of the existing lithostratigraphic nomenclature, sequence stratigraphic analysis is seen as valuable additional tool for a better understanding of the complex geological settings. Even though no detailed investigation has been done till today, it is clear that the marine Jurassic is represented by cyclically arranged mudstones, sandstones, limestones and ironstones and that sedimentation was strongly influenced by sea-level changes in combination with tectonic activities and salt movements. It was possible to subdivide the German Jurassic into 22 regressive-transgressive cycles.

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Jurassic stage definitions: the value of global sequence stratigraphy

Simmons D., Sharland P., Casey D.

Volumina Jurassica

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2006

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Vol. 4, no. 1

215-215

EN

Five years ago we demonstrated the occurrence across the Arabian Plate of 11 synchronous Maximum Flooding Surfaces (MFS) during Jurassic time (Sharland et al. 2001, 2004). Ongoing work, incorporating all the stratigraphy of North Africa and examination of other regions, can now demonstrate the occurrence of 15 Jurassic 3rd order surfaces, and intervening sequence boundaries. Each of our MFS is defined in a Reference Section. This is a location with good sedimentological and/or wireline log evidence for a MFS, supported by biostratigraphy. The biostratigraphy also provides constraint on the correlation of the MFS to its occurrence in other locations. Each of our MFS can be shown to be occurring within the same biozone, or correlative, in different basins across the Middle East and North Africa region. Data from differing fossil groups have been calibrated to the standard zonation for each period. Sequence boundaries are age-calibrated and correlated in a similar manner via their correlative conformities. The ability to recognize and correlate depositional sequences across Arabia and beyond, across basins with differing subsidence and sedimentation rates, indicates that these sequences are driven by synchronous eustatic sea-level change. This observation is of value in providing guidance for the definitions of the fundamental units of chronostratigraphy - stages. Each Phanerozoic stage requires a Global Stratotype Section and Point (GSSP), that is to say, a location and bedding plane where the base of each stage is defined. This definition is tied to an event in the rock record useful for correlation. Progress in defining Jurassic GSSPs has been delayed because of difficulties in choosing the most appropriate (bio)event to relate to definition. It is recommended that stage boundaries be related to bioevents associated with correlative conformities of sequence boundaries. This links chronostratigraphy and sequence stratigraphy and honours the original concepts upon which many stages were first described in the 19th Century.

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Ammonite horizons at the basal Bathonian zone (Parvum Subzone) in Cabo Mondego, Portugal

Fernandez-Lopez S., Henriques M., Manglod Ch.

Volumina Jurassica

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2006

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Vol. 4, no. 1

161-161

EN

The ammonite succession at the Bajocian/Bathonian boundary in the Cabo Mondego region provides one of the most complete biostratigraphical records so far recognized in the Iberian Plate. Lower Bathonian ammonite fossil assemblages are composed of Submediterranean taxa. Parkinsonids characterizing the Northwest European Province, as well as phylloceratids and lytoceratids characterizing the Mediterranean Province, are very scarce. The basal Bathonian zone (Zigzag Zone) established for NW Europe areas, belonging to the Northwest European Province, can be identified in the Lusitanian Basin. The Lower Bathonian boundary may be established by the lowest occurrence of the dimorphic group Morphoceras (M) + Ebrayiceras (m), although morphoceratids are scarce. The Zigzag Zone can be characterized as composed of two subunits (Parvum and Macrescens subzones) represented in diverse European basins of the Submediterranean Province. The revision of previous collections from the classical section and new field samplings of two other separate sections on Cabo Mondego allow to distinguish the lowest subzone of Bathonian (Parvum Subzone, Zigzag Zone). Along up to ten metres of thickness, over forty successive assemblages have been recognized in the Parvum Subzone. The lowermost subzone of the Bathonian yields common perisphinctids (40%), oppeliids (25%) and hecticoceratids (20%), being the most abundant genera: Planisphinctes (m) + Lobosphictes (M), Oxycerites (M) + Paroecotraustes (m) and Nodiferites (m) + Zeissoceras (M). Ammonite fossil assemblages of the Parvum Subzone may be grouped into two successive biohorizons. The lower biohorizon, beginning with the lowest occurrence of Morphoceras (M) + Ebrayiceras (m), has been characterized by perisphinctids of the dimorphic couple Bigotites gr. diniensis Sturani (M) + “Bigotites” acurvatus (Wetzel) in Torrens (m), although they are scarce. The upper biohorizon, through 1.5-2 m of thickening upwards beds, has been identified in the stratigraphic interval beginning with the lowest occurrence of Zigzagiceras (m) + Procerozigzag (M) and underlying the lowest occurrence of Morphoceras macrescens (Buckman). These two successive ammonite horizons are biochronostratigraphically equivalent to the subdivisions of the Convergens Subzone distinguished on the Digne-Barr˘me area (France). The occurrence of Bigotites gr. diniensis (M+m) in Cabo Mondego in the Parvum Subzone represents a new criterion for chronostratigraphical subdivision and chronocorrelation with the Digne-Barr˘me area, useful in understanding the evolution of the West Tethyan Perisphinctidae during earliest Bathonian.

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Pstry piaskowiec w Górach Świętokrzyskich: chronostratygrafia i korelacja litostratygraficzna z basenem turyńskim

Ptaszyński T., Niedźwiedzki G.

Przegląd Geologiczny

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2006

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Vol. 54, nr 6

525-533

EN

The study was performed to attempt the lithostratigraphic correlation of the Buntsandstein in the margin of Holy Cross Mountains region with that of the Thuringian Basin, and simultaneously, to clarify its position in the chronostratigraphic scheme, basing on biostratigraphic data (microflora, conchostracans), and on the existence of regional discordances. The authors found strong analogies with other Buntsandstein sections of the Europe. On the other hand, because of the position of the studied area within the marginal part of the Central European Basin, Buntsandstein of the Holy Cross Mountains region is developed in different facies, more fluvial, instead of lacustrine ones. The common presence of Conchostraca representing the same species as in other parts of the Central European Basin (Thuringia), enables possible the correlation of the investigated area with the Thuringian Basin, and helps to locate stratigraphic gaps and discordances. The authors found that the lower boundary of the Buntsandstein and the boundary between the Lower and Middle Buntsandstein in the Polish study area are not equivalents of those in other areas. Also note worthy is the presence at the margin of the Holy Cross Mountains of youngest Permian terrigenous deposits not connected with the Zechstein salinar sedimentation, included to date to Zechstein or to Buntsandstein. The key for understanding the lithostratigraphic scheme of the Buntsandstein of Holy Cross Mountains region is an assumption, that the Zagnańsk Formation is mostly of fluvial, instead of lacustrine origin, consisting of equivalents of the whole Lower Buntsandstein, and that of the lower Volpriehausen Formation of the Middle Buntsandstein, with the Volpriehausen discordance present within. Authors also assume, that at least in this case, differences in the marginal part of the sedimentary basin, in comparison with its central part, depend on the presence of fluvial facies instead of lacustrine ones, and onthe presence of sedimentary gaps and discordances whose duration is progressively longer towards the basin margin enlarges in the direction to the basin margin.

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Nowe spojrzenie na liczbę, wiek i zasięgi zlodowaceń środkowopolskich w południowej części środkowowschodniej Polski

Lindner L.

Przegląd Geologiczny

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2005

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Vol. 53, nr 2

145--150

EN

An overview of the existing opinions combined with new geomorphological, geological, palaeopedological and TL data allow a new look at the number, age and ranges of the three Middle Polish (Saalian, Dnieperian) Glaciations in central-eastern Poland. During the first of these glaciations (Liviecian), correlated with the 10 oxygen isotope stage in deep-marine deposits (400–360 ka), the Scandinavian ice-sheet advanced in form of a rather narrow lobe, reaching only several tens of kilometres south of Warsaw. During the second glaciation (Krznanian), correlated with the 8 oxygen isotope stage (330–320 ka), it advanced in form of a wider lobe down to the northern margin of the Małopolska and Lublin uplands. In turn, during the third glaciation (Odranian), correlated with the 6 oxygen isotope stage (210–130 ka), the range of the Scandinavian ice-sheet was the largest. It stopped at the elevations of the Quaternary basement in the northern and western part of the Małopolska and Lublin uplands, reaching 330–280 m above sea level. In the study area the discussed glaciations are separated by two interglacials (Zbójnian, Lublinian = Lubavian), correlated with the Reinsdorf and Schöningen interglacials in Germany and Landos and Le Bouchet interglacials in France. The analysed data indicate that within the Odranian Glaciation, its maximum (Kamienna = Drenthe) and postmaximum stadials (Warta = Warthe), as well as two younger recessive stadials (Wkra, Mławka) should be distinguished. Due to the rather wide eastward distribution of the Scandinavian ice-sheets during the two younger glaciations, an attempt has been made to correlate them with the two Dnieperian glaciations in the Ukraine.