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The Lower Kimmeridgian of the Wieluń Upland and adjoining regions in central Poland: lithostratigraphy, ammonite stratigraphy (upper Planula/Platynota to Divisum zones), palaeogeography and climate-controlled cycles

Wierzbowski A.

Volumina Jurassica

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2017

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Vol. 15, no 1

41--120

EN

The Early Kimmeridgian of the Wieluń Upland and adjoining regions, after the decline of sedimentation of the deep-neritic sponge megafacies (Częstochowa Sponge Limestone Fm.) and associated limestones and marls with poor benthic fauna (Pilica Fm.) during the Planula Chron, showed the subsequent development of moderately shallow-water biostromal chalky limestones with siliceous sponges and corals, replaced laterally by micritic limestones and marls (Prusicko Fm.) during the Platynota Chron and the earliest Hypse¬locyclum Chron. Towards the north and south shallow-marine carbonate platforms occurred (represented by deposits of the “oolitic” fm.), whereas towards the north-west and west deeper marine facies, represented initially by limestones with siliceous sponges (Częstochowa Sponge Limestone Fm.), and later during the Hypselocyclum Chron by bedded limestones and marls with ammonites (Burzenin Fm.) were deposited. This palaeogeographic pattern was controlled by the synsedimentary tectonics. The detailed biostratigraphical classification of the deposits studied from the Platynota to the Divisum zones, and their lithological character, enable the recognition of the primary sedimentary cyclicity by comparison with the well dated short eccentricity cycles in the coeval succession of south-eastern France. The two appendixes enclosed give the characteristics of: (1) the characteristics of the ammonite faunas especially of the families Ataxiocerati¬dae and Aulacostephanidae (where two new species are established – Balticeras samsonowiczi sp. nov., and Rasenioides glazeki sp. nov.); (2) the newly established lithostratigraphical units: the Prusicko Fm., and the Burzenin Fm., and the smaller rank units (members, beds) recognized therein.

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Warunki depozycji szczątków kręgowców w osadach środowisk okołopływowych dolnego wapienia muszlowego (anizyku) w kopalni „Stare Gliny” koło Olkusza

Matysik M., Surmik D.

Przegląd Geologiczny

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2016

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Vol. 64, nr 7

495--503

EN

A detailed sedimentological study of the Lower-Middle Muschelkalk (Middle Triassic) carbonate succession exposed at the “Stare Gliny” quarry near Olkusz (Kraków-Silesia region, southern Poland) revealed numerous vertebrate remains within its lowermost sedimentary unit. This 7-m-thick package onlaps a gently-inclined surface of a paleoisland made of the Devonian (Givetian) dolostones, and was deposited during a transgressive phase of the second Middle Triassic transgression onto the southern Poland. The package consists largely of: 1) unfossiliferous dolosiltites and fine-grained dolarenites, the tops of which commonly contain root molds and small-scale karstic forms; 2) breccias (minor conglomerates) with lithoclasts of Givetian dolostones; 3) dolocretes; and 4) dolomitic shales. This lithofacies association represents a restricted lagoon which experienced longer periods of emersion. A minor occurrence of cryptalgal laminites reflects only temporary sedimentation in the intertidal zone of a tidal flat. The bone fragments occur within all types of lithofacies, but the macroscopically distinguishable specimens have been found exclusively in the dolocretes. The poor preservation and advanced disarticulation of bones hinder unequivocal assessment of their affinity. The small size of bones suggests that they represent prolacertiforms (perhaps juvenile Macrocnemus) or other small archosauromorphs similar in sizes to Protorosaurus or Czatkowiella whose remains were found in the 1950s within cave deposits, in the same outcrop. Macrocnemus widely inhabited Middle Triassic lagoons and tidal flats across Paleo-Europe and thus seems to fit well to the peritidal setting surrounding the “Stare Gliny” paleoisland. The bone-bearing package occurs 30 metres below the 5-m-thick oncolitic package that is widely regarded as a correlation horizon over the entire Kraków-Silesia region, and 15 metres below the sequence boundary marking the top of the Górażdże Beds in the Opole region and the Olkusz Bedsin the Kraków-Silesiaregion.On the basis of the secor relations,a conclusion can be made that the vertebrate assemblage is Bithynian/Pelsonian (middle Anisian) in age.

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Recent studies on the Silurian of the western part of Ukraine

Łuczyński P., Skompski S., Kozłowski W.

Acta Geologica Polonica

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2016

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Vol. 66, no. 3

281--297

EN

The paper summarises the effects of recent studies carried out by a team from the Department of Historical and Regional Geology of the Faculty of Geology, University of Warsaw on the upper Silurian of Podolia (western part of Ukraine). The sedimentary history of the Silurian succession of Podolia is characterised by its cyclic pattern, with shallowing-upward cyclothems. In the traditional interpretation, the occurrence of stromatoporoid beds within each cyclothem marks the deepest (or most open-marine) sedimentary environment within the cycle. According to the results of recent studies, their occurrence is connected rather with a relatively shallow-water environment and with high energy phenomena. A substantial reinterpretation of the main sedimentary processes governing the deposition and facies distribution on the shelf is presented. Particularly, there are recognised and described high-energy sedimentary events repeatedly punctuating the generally calm sedimentation that prevailed in the lagoonal settings, some of which are interpreted as tsunami induced. Further perspectives for studies on the Silurian successions of Podolia are also discussed. The main problem is the precise correlation of particular sections that are scattered over vast distances and developed in similar facies associations.

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Facies and diagenetic evolution of the Bathonian-Oxfordian mixed siliciclastic-carbonate sediments of the Habo Dome, Kachchh Basin, India

Ahmad A. H. M., Irshad R., Bhat G. M.

Volumina Jurassica

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2015

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Vol. 13, no. 1

83--104

EN

This paper examines the depositional environment and diagenetic aspects of the exposed Patcham and Chari formation within the Habo Dome. The Patcham Formation is represented by the Black Limestone Member. The Chari Formation is represented by two distinct sedimentary successions: (i) shale and carbonates, and (ii) coarse clastics. The paper describes eleven lithofacies from these successions. The depositional framework constituents of these facies have been greatly modified by diagenetic evolution through time. Two main depositional environments, i.e. foreshore intertidal and shoreface (subtidal), have dominated during their deposition. The diagenetic signatures observed within these sediments suggest early or syndepositional changes in marine phreatic and burial environments. Two phases of early mechanical compaction have largely governed porosity evolution within the limestone facies. Micritization of the allochems was caused by endolithic algae prevalent within the restricted lagoon environments with stagnant marine phreatic zone conditions. Random dissolution of microcrystalline grains has created vugs with patchy distribution reflecting neomorphism within the meteoric vadose zone. The types of cements within the sandstone facies include silica, calcite, and its replacement by Fe-calcite cement. The sandstones were deposited in a relatively low energy environment below storm wave base. The depositional conditions have controlled the early diagenesis of the sandstones which in turn have influenced their burial diagenesis.

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Silicified sea life – Macrofauna and palaeoecology of the Neuburg Kieselerde Member (Cenomanian to Lower Turonian Wellheim Formation, Bavaria, southern Germany)

Schneider S., Jäger M., Kroh A., Mitterer A., Niebuhr B., Vodrážka R., Wilmsen M., Wood C. J., Zágoršek K.

Acta Geologica Polonica

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2013

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Vol. 63, no. 4

555--610

EN

With approximately 100 species, the invertebrate macrofauna of the Neuburg Kieselerde Member of the Wellheim Formation (Bavaria, southern Germany) is probably the most diverse fossil assemblage of the Danubian Cretaceous Group. Occurring as erosional relicts in post-depositional karst depressions, both the Cretaceous sediments and fossils have been silicified during diagenesis. The Neuburg Kieselerde Member, safely dated as Early Cenomanian to Early Turonian based on inoceramid bivalve biostratigraphy and sequence stratigraphy, preserves a predominantly soft-bottom community, which, however, is biased due to near-complete early diagenetic loss of aragonitic shells. The community is dominated by epifaunal and semi-infaunal bivalves as well as sponges that settled on various (bio-) clasts, and may widely be split into an early bivalve-echinoid assemblage and a succeeding sponge-brachiopod assemblage. In addition to these groups we document ichnofauna, polychaete tubes, nautilids and bryozoans. The fauna provides evidence of a shallow to moderately deep, calm, fully marine environment, which is interpreted as a largescale embayment herein. The fauna of the Neuburg Kieselerde Member is regarded as an important archive of lower Upper Cretaceous sea-life in the surroundings of the Mid-European Island.

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Early Aptian bay deposits at the southern margin of the Lower Saxony Basin : Integrated stratigraphy, palaeoenvironment and OAE 1a

Lehmann J., Friedrich O., Bargen D., Hemker T.

Acta Geologica Polonica

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2012

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Vol. 62, no. 1

35-62

EN

The present study establishes a lithostratigraphic subdivision, a bio- and chemostratigraphy and describes the sedimentology of the Alstatte Bay at the southern margin of the Lower Saxony Basin in northern Germany. The socalled Fischschiefer is developed in the lower part of the section, a 2.1 m thick laminated interval that shows TOC values of up to 2 % and is interpreted as local expression of the global Oceanic Anoxic Event 1a (OAE 1a). The basal part of the Fischschiefer is fairly continuously laminated, whereas its upper part is characterized by an alternation of laminated and non-laminated beds. Stable carbon isotopes ([delta^13]C[carb]) show a characteristic pattern for the Fischschiefer interval that can be correlated with sections from the Tethyan Realm. Immediately above the Fischschiefer, however, the studied section might reveal a diagenetic overprint as indicated by very negative carbon stable isotope values. The remaining part of the section is characterized by a rather monotonous claystone succession, terminated by a greenish layer rich in glauconite overlain by glacial till of Pleistocene age. The fauna is typically Boreal in the lower part of the section, but changes around 2 m above the Fischschiefer towards an assemblage indicating a distinct Tethyan influx. The faunal shift is considered to be due to the maximum flooding of the continuous, long-term sea level rise of the Early Aptian which led also to a supposed shift from a restricted to open bay environment.

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Kambr górny we wschodniej części regionu kieleckiego Gór Świętokrzyskich : komunikat wstępny

Szczepanik Z., Trela W., Salwa S.

Przegląd Geologiczny

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2004

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Vol. 52, nr 9

895--898

EN

The paper deals with new data from Lenarczyce PIG 1 well that drilled the Upper Cambrian deposits – hitherto unknown in the southern part of the Holy Cross Mts. The sedimentary record is composed of conglomerates, sandstones and mudstones that form up to 90-m-thick succession. Preliminary palynological studies indicate presence of a morphologically variable and well preserved Upper Cambrian acritarch assemblage. The well log can be divided into two parts due to differences in the tectonic style arrangement. The lower part (from bottom [= ? m] up to the depth of 128 m) reveal strong tectonic deformation demonstrated by the changing dips from horizontal through vertical to reversed. To the contrary, the upper part (above 128 m depth) shows lesser dips alternation and lack of folds. Both recognized structural complexes yield completely different acritarch assemblages.

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Sedimentary evolution of Badenian (Middle Miocene) gypsum deposits in the northern Carpathian Foredeep

Kasprzyk A.

Kwartalnik Geologiczny

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1999

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Vol. 43, Nr 4

449-465

EN

In the northern peripheral part of the Carpathian Foredeep, the Middle Miocene (Badenian) gypsum deposits comprise two major, laterally extensive members: the lower is mostly autochthonous, of selenitic facies and the upper is allochthonous, of clastic facies and cumulate deposits. Towards the south, gypsum is replaced in the subsurface by anhydrite which displays relict textures of the primary gypsum. The facies variation and succession throughout the gypsum section, as well as geochemical indicators, reflect varied sedimentary conditions on the basin margin. Deposition took place on the periphery of a platform made up of a system of widespread shallow-water lagoons (sub-basins) separated by fault-controlled, NW-SE elongated islands or shoals. In these physiographically differentiated palaeoenvironments, facies relationships were largely diachronous. The water depth varied from a few metres to some tens of metres, and subaerial exposure episodically affected the gypsum deposition, as suggested from the sedimentary record and comparison of the facies with modern evaporitic environments. Variations in brine depth, salinity and water dynamics are expressed in the cyclic succession of the progressively changing facies associations. Sedimentary conditions changed drastically at the boundary of the lower (selenitic) and upper (clastic) members, and at the end of sulphate deposition, following major sea-level changes.

PL

Gipsy badeńskie są szeroko rozprzestrzenione w północnej, peryferyjnej części zapadliska przedkarpackiego, gdzie są znane z licznych odsłonięć powierzchniowych i otworów wiertniczych. Osady te wykazują duże zróżnicowanie litofacjalne i tworzą w profilu stałą sekwencję warstw (od a do r) składających się na dwa podstawowe kompleksy: dolny (głównie gipsy autochtoniczne, selenitowe) i górny (głównie gipsy allochtoniczne, klastyczne i drobnokrystaliczne). Ku południowi, wraz ze wzrostem głębokości występowania (powyżej 250 m), gipsy są częściowo lub całkowicie zastąpione przez anhydryty zachowujące wiele struktur pierwotnych skal gipsowych. Zmienność facji i ich następstwo, a także skład geochemiczny odzwierciedlają zmienne warunki sedymentacji w brzeżnej strefie zbiornika badeńskiego. Warunki te zrekonstruowano na podstawie podobieństwa litofacji do osadów współczesnych środowisk ewaporacyjnych. Gipsy selenitowe tworzyły się w środowiskach płytkowodnych poddanych okresowym wynurzeniom, natomiast depozycja grubego kompleksu gipsów klastycznych miała miejsce w środowisku głębszym. Gipsy powstawały na platformie w rozległych, płytkowodnych lagunach (salinach, subbasenach). Rozdzielały je lokalne wyspy lub płycizny o kierunku NW-SE, mające założenia tektoniczne. Wyróżnione asocjacje facjalne gipsów: przybrzeżna (NFA), płytkowodna (SFA) i głębokowodna (DFA) reprezentują główne systemy depozycyjne platformy siarczanowej: ( 1 ) strefy brzegowej (sebha - salina przybrzeżna), (2) płytkiej, wewnętrznej części platformy, i (3) głębszej, zewnętrznej części platformy. W strefie peryferyjnej zbiornika depozycja gipsów miała miejsce w zróżnicowanych środowiskach. Osady sebhy wykształciły się na równiach przybrzeżnych, które okresowo pokrywały znaczna część platformy wewnętrznej w czasie niskiego stanu wód. Facje stromatolitowe tworzyły się w środowiskach od skrajnie płytkowodnych do subaeralnych, natomiast gipsy selenitowe rozwijały się na dnie płytkich (o głębokości do kilku metrów) lagun, częściowo izolowanych od wpływu otwartego morza. W warunkach płytkowodnych osad gipsowy był łatwo redeponowany w okresach zwiększonej dynamiki wód. W wodach głębszych, gęstościowo rozwarstwionych, depozycji gips klastycznych towarzyszyło wytrącanie gipsu w toni wodnej. Stwierdzone cykliczne następstwo asocjacji facjalnych w profilach gipsów badeńskich odzwierciedla zasadnicze zmiany środowiska sedymentacji w peryferyjnej części zbiornika. Głównymi czynnikami determinującymi charakter i sukcesję osadów były względne zmiany głębokości, dynamiki i zasolenia wód. Najbardziej drastyczne zmiany środowiska sedymentacji, które można wiązać z większymi zmianami poziomu morza, zaznaczyły się na granicy depozycji kompleksu gipsów selenitowych i kompleksu gipsów klastycznych, a także pod koniec depozycji gipsów.

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Facies and depositional environments of the Nida Gypsum deposits (Middle Miocene, Carpathian Foredeep, southern Poland)

Bąbel M.

Kwartalnik Geologiczny

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1999

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Vol. 43, Nr 4

405-428

EN

Seven facies (five primary and two diagenetic) and 12 subfacies are distinguished within the Nida Gypsum deposits which are a part of the widespread Middle Miocene (Badenian) evaporites of the Carpathian Foredeep cropping out in vicinity of Busko in southern Poland. Facies are defined as products of specific mechanisms of evaporitic deposition: syntaxial bottom growth of gypsum crystals, microbial gypsum deposition (mainly gypsification of organic mats), mechanical deposition and diagenetic and weathering processes. Primary facies and subfacies, and their uncommon sedimentary structures (such as: up to 3.5 m high bottom-grown gypsum crystals, several metres high selenitic domes, gypsum stromatolite domes, halite-solution collapse breccias) record a varied shallow water (0-5 m) evaporitic environment, controlled mainly by depth, salinity and climate.

PL

W badeńskich gipsach Ponidzia wyróżniono 6 facji siarczanowych: gipsy szklicowe, rumosze kryształów gipsu, gipsy trawiaste, szablaste, mikrokrystaliczne, porfiroblastyczne i jedna fację węglanową. W obrębie 5 pierwszych facji wyróżniono 12 subfacji i scharakteryzowano środowiska ich sedymentacji, które w większości są typowe dla płytkiego, okresowo wynurzanego zbiornika ewaporacyjnego. Facje zdefiniowano jako produkty kilku podstawowych mechanizmów depozycyjnych (por. E.Mutti, F.Ricci Lucchi, 1975), m.in. takich jak: (I) syntaksjalny wzrost dużych kryształów gipsu wprost na dnie basenu (gipsy szklicowe, trawiaste i szablaste), (II) mikrobialną (sensu R.V.Burne, L.S.Moore, 1987) depozycję drobnokrystalicznego gipsu, głównie poprzez gipsyfikację mat organicznych (gipsy trawiaste), (III) depozycję mechaniczną (gipsy mikrokrystaliczne), obejmującą opadanie i osiadanie drobnych kryształów gipsu wytrąconych w tonu wodnej, oraz redepozycję osadu gipsowego. Zróżnicowanie facjalne gipsów Ponidzia wynika przede wszystkim z wahań zasolenia i głębokości basenu oraz wilgotności klimatu.