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EN
In the Pieniny Klippen Belt (PKB), the Cretaceous and Paleogene conglomerates and cohesive debrites commonly contain pebbles and blocks of the subvolcanic rocks among other, mainly sedimentary rocks (e.g. multicoloured sandstones, oolitic limestones, dark bivalve coquinas, dolostones, etc.). This detritus was interpreted as derived from the Andrusov Ridge located south of the PKB basin (Birkenmajer, 1988). Age of these subvolcanic rocks, regarded to represent subduction-related igneous activity, was previously constrained by K-Ar whole rock dating as c. 140–90 Ma, leading to suggestion that during Late Jurassic to Early Cretaceous PKB basin developed on oceanic lithosphere, subducted during at the end of Early Cretaceous (Birkenmajer, 1988). Within this study, the geochemical composition, the K-Ar whole rock age and the U-Pb zircon ages of the above mentioned subvolcanic rocks were studied. The pebbles are well rounded. They are represented by granitic and subvolcanic andesitic-type rocks (mainly andesite, basaltic andesite, basaltic trachyandesite, trachyandesite and rhyolitic pebbles, and rare dacite, tephrite, trachybasaltic and basaltic pebbles). Domination of andesitic pebbles, bimodal spectrum of volcanic rocks with high content of SiO2 (rhyolites, dacites) and Na2O and K2O within mafic and transitional ones is observed. Their petrographic character and geochemical analysis of concentration of rare elements with MgO > 2% ratio and La/Yb 4–35, Sc/Ni < 1.5, Sr/Y < 20, Ta/Yb > 0.1, Th/Yb > 1 values, indicate magmatic island arc of active continental margin similar to Andean-type subduction regime. The K-Ar whole rock dating was performed for 17 samples. The obtained ages cover mainly the Early Cretaceous time span, with the most data representing the Barremian-Albian, therefore are coherent with Birkenmajer (1988) results. However, the U-Pb SHRIMP zircon dating reveled different results. Most of the analyzed subvolcanic rock samples (9) give ages in the narrow range of c. 270–266 Ma. The ages are based on concordant data with amount of measured point in a range of 20–30, and are characterized by low error bars, usually lower than ±2 Ma. In addition, one sample of subvolcanic rock gave lower quality results, with a few youngest, partly concordant, zircons grains giving the age of 251.0 Ma ±8.5 Ma. Moreover, one sample of orthogenesis was analyzed, which is regarded to represent crust on which the volcanic arc developed. In this case the U-Pb SHRIMP zircon dating result is 493.9 Ma ±4.1 Ma. We regard these pebbles/blocks to be derived from the Inner Carpathians, assuming therefore lack of the Andrusov Ridge located south of the PKB basin (comp. Plašienka, 2018). The results of K-Ar whole rock dating is representative for intensive diagenetic overprint, rather than age of the rock. The U-Pb data clearly indicate, that subduction-related magmatic arc developed during the middle Permian (Guadalupian). This follows, that the oceanic crust was of the middle Permian or older age, and thus cannot be related to the Jurassic-Early Cretaceous development of the PKB basin. The magmatic arc was presumably connected with southern margin of Laurusia and subduction of oceanic crust of the Paleotethys (proto-Vardar Ocean?).
EN
The major Mesozoic palaeogeographic disintegration of the present-day transitional area between the Alps and the Dinarides (Slovenia) occurred due to the Middle Triassic rifting event related with the opening of the Neotethys Ocean. By the Norian, three major palaeogeographic units were formed: the Dinaric (Adriatic, Friuli) Carbonate Platform (DCP) in the south, intermediate, E-W extending Slovenian Basin (SB) and the Julian Carbonate Platform (JCP) in the north. The platforms were characterized by a Dachstein type platform, while the basin was filled with hemiplegic and resedimented limestones, most of which are now dolomitized. To the west, there was a shallow water “bridge” between the two platforms. After the Triassic-Jurassic Boundary crisis, the palaeogeographic setting was preserved, but the margins of the platforms turned into ooidal factories. During the Early Jurassic, SB was almost exclusively filled with ooid calciturbidites from the north, which can be explained by the wind/leeward position of the basin with respect to the particular platform. The first rifting phase of the opening Alpine Tethys, generally dated to the earliest Jurassic, is poorly expressed in this area. The main products are limestone breccias that occur in the western part of the SB. In contrast, the second rifting phase (dated to the Pliensbachian in Slovenia) completely disintegrated JCP. The margins subsided first and were characterized by open shelf conditions with crinoid meadows, while the inner parts of the JCP remained shallow-marine. In the SB, the initial subsidence can be seen in the altered composition of the calciturbidites. Namely, the ooid/peloid dominated resediments changed to crinoid/ lithoclast dominated. In the Toarcian, sedimentation ended on most of the JCP, with only sporadic marls occurring at the margins. At the same time, the sedimentary environment of the DCP also deepened and nodular or crinoid limestone was deposited. The SB is characterized by uniform clay-rich sediments that vary greatly in thickness, indicative of differential subsidence caused by the second rifting phase. In the Middle Jurassic, shallow-water sedimentation re-established on the DCP, the margin being characterized again by ooidal shoals, the sedimentation of the SB gradually changed to siliceous limestone, while the JCP and the “bridge” between the JCP and DCP are characterized by non-sedimentation. The last important Jurassic change occurred during the Bajocian-Bathonian stages. Condensed Ammonitico Rosso-type limestone began to be deposited on the “bridge” and the JCP, while sedimentation in the SB changed to pure radiolarite. In the past, this was interpreted as a result of thermal subsidence associated with oceanization of the Alpine Tethys. However, studies in the last decade suggest a more complex tectonic evolution. Because the area in question lies between the opening Alpine Tethys to the west and the concurrent onset of subduction of the Neotethys to the east, it has been subject to strong differential subsidence between the largescale DCP and all units north of it. The exact nature of the tectonic deformation is not yet clear, but a transtensional regime is most probable. These events resulted in the disintegration and collapse of the northern DCP margin, as evidenced by the sedimentation of limestone breccia megabeds along the entire SB southern margin. These megabeds not only indicate enhanced tectonics, but also provide important information about the pre-Middle Jurassic architecture of the DCP margin, which is no longer preserved. They consist of very diverse limestone lithoclasts and an ooid packstone matrix. Analysis of the clasts revealed that the Late Triassic DCP margin was characterized by Dachstein-type reefs and the Early Jurassic by ooid shoals. In the interior of SB, these strata merge into ooid calciturbidites interlayered between radiolarite and become completely wedged in the northern part of the basin. Corresponding gravity-flow deposits also sedimented on the subsided “bridge” between the DCP and the JCP, and even on the northern margin of the DCP itself. An important difference is the simpler composition of the resediments in this area. Namely, they consist entirely of Middle Jurassic platform margin and slope lithoclasts. This is explained by the less pronounced palaeotopography between the active platform and submerged “bridge”, which did not allow erosion of the older platform limestone (as observed in SB). The described collapse of the DCP margin caused it to retreat, and marginal reefs formed over the underlying inner platform limestones in the Late Jurassic. The emersion phase in the Kimmeridgian ended reef growth and the margin turned back into ooid rich shoals. At the same time, the SB was characterized by continuous radiolarite sedimentation and drowned JCP together with the “bridge” with the Ammonitico rosso facies, characterized by several stratigraphic gaps. Rare calciturbidites are interbedded in areas near the DCP (southern SB and a drowned “bridge”). At the end of Jurassic, all areas north of the DCP show uniform sedimentation of the Biancone Limestone Formation.
EN
An update of the main Devonian pre-Variscan palaeogeographical features of the southern Cantabrian Zone is presented. The approximal locations of these features are recorded in sections studied, with thin, incomplete developments for the highs and thick successions for the troughs. Generally, pre-Variscan palaeogeographical features were affected by Variscan and Alpine orogenic deformations, but with a different impact. Oroclinal bending, tectonic shortening by thrusts, movements along strike-slip faults and bending by folds all affected the Devonian palaeogeographical features, and only an approximation of their location and shape can be given. Nevertheless, the palaeogeography recorded in pre-Variscan sedimentary successions and their relative positions, provide specific, clear and objective evidence of the pre-Variscan elements.
EN
The Middle Eocene Akhoreh Formation is superbly exposed in the western corner of the Central-East Iranian Microcontinent (CEIM). This formation covered the northeastern flank of the Cretaceous Nain Ophiolite Mélange (NOM) and is adjacent to the Paleogene Urmieh–Dokhtar Magmatic Arc (UDMA) formed in the southwest of the CEIM. This terrigenous succession is composed of a thin basal conglomerate followed by mostly pink to purple sandstones alternating with shales. The clast composition and clast imbrication of the conglomerates show local source areas towards the north-north-east. Modal components of lower Akhoreh Formation sandstones reveals immature lithic arkose (Q8F48L44) and feldspathic litharenite (Q8F44L48) sandstones that are rich in mafic and ultramafic igneous and volcanic rock fragments. Mafic to ultramafic source rocks are also indicated by geochemical data (enrichment of Mg, Cr and Ni and Cr/V) in the sandstone and shale samples analyzed. However, geochemical data suggests an intermediate igneous rock origin for the shale samples studied, most likely from the nearby continental arc. Based on petrographic data, these sandstones have characteristics of a transitional to undissected arc tectonic setting. Geochemical discrimination diagrams using major and trace elements indicate an oceanic island arc tectonic setting for the lower Akhoreh Formation sandstones and shales, probably due to a predominance of ophiolitic source rocks. Furthermore, the chemical index of alteration and modal analysis indicate a weak to moderate degree of chemical weathering with arid climatic conditions in the source area. The exhumed NOM, together with the UDMA in the southwest, were dominant sources of sediment to the lower Akhoreh Formation, that lay to the northeast in a local retroarc basin of the Central Iranian Microplate, during the Middle Eocene.
EN
We report an extraordinary discovery of marine Pleistocene strata from the north of the Persian Gulf. The Dayyer section contains a rich molluscan fauna including 26 bivalve species, Sr87/Sr86 data showing that the succession is not older than 153 ka (late Pleistocene). These strata are time-equivalents of the Bakhtiari Formation, but have a very different fossil content and facies. Comparing the Dayyer molluscan community to the present-day fauna of the Persian Gulf shows that many fossil species are absent in the recent waters. The palaeoceanographic distribution of the identified bivalves shows the presence of many of them in the Plio-Pleistocene strata of the Mediterranean Basin. This may point to a temporary connection between the Persian Gulf and Mediterranean Basin during the late Pleistocene and the extinction of many bivalves in the past 153 ka
EN
The paper focuses on the taxonomic description of the lower Carboniferous (uppermost Tournaisian to middle Viséan) solitary rugose corals from bedded limestone and shale units in the Flett Formation in the Jackfish Gap (eastern Liard Range), northwestern Canada. The corals described herein include 12 species representing the genera Ankhelasma Sando, 1961, Bradyphyllum Grabau, 1928, Caninophyllum Lewis, 1929, Cyathaxonia Michelin, 1847, Ekvasophyllum Parks, 1951, EnniskilleniaKabakovich in Soshkina et al., 1962, Vesiculophyllum Easton, 1944 and Zaphrentites Hudson, 1941. Two of these species are new (Ankhelasma canadense sp. nov. and Ekvasophyllum variabilis sp. nov.) and 6 taxa are described in open nomenclature. The distribution and relative abundance of solitary Rugosa in Europe and the Liard Basin confirm the geographical proximity of those areas and the open marine communication between them during the early Carboniferous. It therefore represents an important contribution to the determination of the time of isolation of the western Laurussia shelf fauna from that of southeastern Laurussia, as well as the time of the possible emergence of species from southeastern Laurussia into the western Laurussia seas. Of particular importance here are cosmopolitan taxa and the timing of their disappearance from the fossil record.
EN
The studies were conducted on the barrier coast located in the eastern part of Pomeranian Bay. The main study goal was to present the development of the barrier coast between Niechorze and Kołobrzeg, with particular emphasis on the impact of sea level changes in the Baltic Sea. Based on collected data, three basic groups of deposits were identified in the study area: barrier basement deposits, barrier deposits, and Rega River outlet cone deposits. To recreate the barrier development stages, sea level changes in the eastern part of Pomeranian Bay for the last 8,500years were reconstructed. At that time, the coast migrated to the south. The first barriers in the study area appeared around 7,500years b2k. The main factors conditioning the barrier coast development in were climate changes, sea level changes, barrier basement morphology and lithology, as well as the amount of supplied sedimentary material. The reconstructed stages of barrier development show that there are sections of different barrier types (landward-migrating to accreted barrier, landward-migrating barrier through accreted barrier to landward-migrating barrier, landward-migrating barrier) in the study area.
EN
The sedimentary and stratigraphic patterns established for Zechstein of the western part of the Peribaltic Syneclise (and in particular the eastern Łeba Elevation) were applied to other parts of the East European Craton (EEC) in Poland: the eastern Peribaltic Syneclise and the Podlasie region. A very large number of mostly fully-cored borehole sections in the Puck Bay region certainly predestines the eastern Łeba Elevation area to use it as a model. The most part of the EEC, except of its part adjacent to the Teisseyre-Tornquist Zone, during the Zechstein deposition represents the marginal parts of the basin. The fauna occurring in the Zechstein carbonate deposits of the EEC makes it possible to distinguish between the Zechstein Limestone and the younger carbonate strata, but certainly not between the Main Dolomite and the Platy Dolomite and hence the facies models for the Zechstein that have been previously developed in the western part of the Peribaltic Syneclise augmented by sequence stratigraphic approach seem to be the best tool to apply in other peripheral areas in the EEC area. The Zechstein sequence in the western part of the Peribaltic Syneclise consists, in general terms, of three parts: (1) carbonate platform of the Zechstein Limestone (occurring only in the north-westernmost corner of the study area and passing into basin facies dominant in the most part of the area); (2) the PZ1 evaporite platform system composed of sulphate platforms and adjacent basin system and constituting the major part of the Zechstein sequence; and (3) the Upper Anhydrite-PZ3 cover. There is a consensus, as far as the western part of the Peribaltic Syneclise is concerned, that the Platy Dolomite platform is wider than the Main Dolomite platform. In the easternmost part of the Peribaltic Syneclise, the stratigraphical interpretations are diverse. We have included the anhydrite overlying the Zechstein Limestone into the Upper Anhydrite, and concluded that the overlying interbedded mudstone and anhydrite also belong to the Upper Anhydrite. When above the Upper Anhydrite one carbonate unit occurs, it is assigned either to the Main Dolomite and Platy Dolomite, or to the Platy Dolomite. The same conclusion is proposed for the marginal parts of the Podlasie Bay. The deposition of Zechstein Limestone resulted in the origin of carbonate platforms along the basin margins which changed an inherited topographic setting. The Lower Anhydrite deposits are lowstand systems tracts (LST) deposits, lacking in more marginal parts of the western and eastern Peribaltic Syneclise and in the major part of the Podlasie Bay. The accommodation space existed and/or created during the Lower Anhydrite and the Oldest Halite deposition in the Baltic and Podlasie bays was filled and at the onset of the Upper Anhydrite deposition, a roughly planar surface existed except in the area ad jacent to the main Polish basin. The Upper Anhydrite deposits are transgressive systems tracts deposits and then highstand systems tracts deposits and they encroached the Zechstein Limestone platforms. The Upper Anhydrite deposition was terminated by sea level fall, and the Upper Anhydrite deposits in the marginal areas became subject to karstification. The Main Dolomite transgression took place in several phases but its maximum limit did not reach the Upper Anhydrite limit. The deposition of the PZ2 chlorides (LST deposits) resulted in the filling of the accommodation space that was inherited after the deposition of the Main Dolomite and the Basal Anhydrite. Subsequently, the area became exposed, and marine deposits (Grey Pelite and Platy Dolomite) related to the last major transgression during the life of the Zechstein basin that resulted in a flooding of the exposed surface of older Zechstein deposits, including the area that was emergent during deposition of the PZ2 cycle. Microbial carbonates, being stromatolites and thrombolites, are a common feature of all Zechstein carbonate units but in particular this is the case of the Platy Dolomite. There are no direct premises allowing for convincing settlement doubts regarding the stratigraphical position of the upper carbonate unit in many cases, but several lines of evidence suggest that, as in the entire Zechstein basin, the Main Dolomite considerably shifted basinward, and the Platy Dolomite - landward, although it is difficult to ascertain whether the original Platy Dolomite extent was similar to or greater than the limit of the Zechstein Limestone as elsewhere in the Zechstein Basin.
EN
In the Ukrainian part of the Silesian Nappe (Outer Carpathians, Uzh River Basin) the exotic clast-bearing Uzhok Olistostrome (up to 60 m thick) occurs within the Oligocene Krosno Formation and underlies the Pikui Sandstone (Otryt Sandstone in Poland). The Uzhok Olistostrome consists of debris/grain/mud flow deposits with clasts of schist and bioclastic limestone. These deposits contain redeposited pelagic sediments with planktonic foraminifers including Parogloborotalia pseudocontinuosa (Jenkins), Ciperoella ciperoensis (Bolli), Globoturborotalita woodi (Jenkins), Chiloguembelina adriatica Premec Fucek, Hernitz Kucenjak and Huber. The age of the Uzhok Olistostrome based on planktonic foraminifers correlates with the middle Oligocene within the middle O2–O5 zones. The source area for the Uzhok Olistostrome and Pikui Sandstone was a mid-Oligocene intrabasinal palaeouplift (the Pikui Ridge) interpreted as the fore-bulge located in the Silesian Sub-basin ahead the emerging Outer Carpathian accretionary prism (including the Dukla Nappe and other West Carpathian inner flysch nappes).
EN
The paper is focused on the palaeographic development of the western part of the Holy Cross Mountains, Poland, during the maximum extent of the Sanian 2 (MIS 12) ice sheet and its retreat. The studies were based on archival cartographic data, coupled with new lithological and petrographic analyses of limni- and fluvioglacial sands, i.e., grain-size composition, quartz grain morphology and heavy mineral analysis, as well as analysis of the erratic material of tills. The results confirm the regional variability of the erratic material in the Sanian 2 tills and point to the long-term development of fluvioglacial sands cover documenting cold climate conditions. They also evidence that the western part of the Holy Cross Mountains was the area where two oppositely directed ice sheet lobes (Radoszyce and Sandomierz) advanced during the Sanian 2 Glaciation and that deglaciation of the area took place in two stages. Huge quantities of meltwater released at that time contributed to the intensification of earlier initiated karst phenomena, as well as filling of the existing caves by fluvioglacial sands.
EN
Rare erratic clasts - extraneous rock types - occur in the Upper Cretaceous Chalk, including a local basal facies, the Cambridge Greensand. The underlying Upper Albian Gault Clay and the Hunstanton Red Chalk Formations have also yielded erratics. The discovery of these erratics, their description and the development of hypotheses to explain their origins and significance are reviewed. They became the subject of scientific interest with the interpretation of a particularly large example “The Purley Boulder” by Godwin-Austen (1858) as having been transported to its depositional site in the Chalk Sea by drifting coastal ice. Thin section petrography (1930–1951) extended knowledge of their diverse provenance. At the same time the Chalk Sea had become interpreted as warm, so drifting ice was considered out of context, and the preferred agents of transport were entanglement in the roots of drifting trees, as holdfasts of floating marine algae, or as stomach stones of marine reptiles or large fish. Reconsideration of their occurrence, variable nature and sedimentary setting suggests that there are three zones in the English Chalk where erratics may be less rare (1) near the base of the Cenomanian in the Cambridge area, (2) the Upper Cenomanian-Middle Turonian in Surrey, and (3) the Upper Coniacian and Lower Santonian of Kent. The assemblage from each level and their sedimentary setting is subtly different. Present evidence suggests that the erratics found in the Upper Albian-Lower Cenomanian and the Upper Cenomanian-Middle Turonian zones represent shallow water and shoreline rocks that were transported into the Chalk Sea by coastal ice (fast-ice) that enclosed coastal marine sediments as it froze. The Upper Coniacian and Lower Santonian erratics from Rochester and Gravesend in Kent are gastroliths.
EN
According to the current state of research five sand-gravel accumulation levels of Quaternary age are visible in the morphology of the western part of the Holy Cross Mountains, within the Wierna Rzeka, Hutka and Bobrza river valley systems and the lower stretches of the Biała Nida and Czarna Nida river valleys. Two upper levels (V and IV) correspond to valleys formed during the Odranian Glaciation-Saalian, MIS6 and its reccesional phases under the influence of proglacial and extraglacial waters beyond the extent (to the east) of the maximal ice-sheet limit of this glaciation, reaching to the present-day Leśnica-Gnieździska-Łopuszno line. Two lower levels (III and II) are terraces that were typically formed during the climatic conditions thatprevailed during Vistulian stadials. Sands and gravels of the three upper levels (V−III) contain numerous debris flow deposits and cryoturbation structures documenting periglacial conditions during their accumulation. The lowermost level (I) is a typical Holocene floodplain.
EN
Tectonic setting of both the uppermost Triassic Tomanová and the lowermost Jurassic Dudziniec formations can be characterized by a series of diagnostic discrimination diagrams. High-silica and low-silica multi-dimensional diagrams indicate that the sediments could have been deposited in the continental collision/rift setting. Diagrams of K2O/Na2O versus SiO2, SiO2/Al2O3 versus K2O/Na2O and Th-Co-Zr/10 as well as Th-Sc-Zr/10 determine an origin from the tectonically active and/or passive continental margin setting. REE parameters indicate predominantly a passive margin tectonic setting of the sediments. The most probable source of clastic admixture in the Scythian to Domerian sediments in the Tatric Unit was situated in a remnant of the Variscan collisional orogen - the Vindelician Highlands. Occasional monsoonal rains occurring in orbitally controlled cycles transported weathered material from the source area down river valleys on the seaward slopes of the Variscan Vindelician Mountains towards the Tethyan Sea. The input of this material influenced also the marginal parts of the Fatricum (e.g., Vysoká or Havran units).
EN
This study presents the first zircon U-Pb LA-MC-ICP-MS ages and whole-rock Rb/Sr and Sm/Nd data from exotic blocks (Bugaj and Andrychów) from the Western Outer Carpathians (WOC) flysch. The CL images of the zircon crystals from both samples reveal typical magmatic textures characterized by a well-defined concentric and oscillatory growth zoning. A concordia age 580.1 ± 6.0 Ma of the zircons from the Bugaj sample is considered to represent the crystallization age of this granite. The zircon crystals from the Andrychów orthogneiss yield an age of 542 ± 21 Ma, interpreted as the uppermost Proterozoic, magmatic crystallization age of the granitoid protholith. The initial (at ca. 580 Ma) 87Sr/86Sr ratios of the Bugaj granitoids (0.72997 and 0.72874) are highly radiogenic, pointing to the assimilation of an older, possibly strongly Rb enriched source to the Bugaj melt. The Nd isotope systematics (εNd580 –1.4 and 0.4) also point to a significant contribution of such a distinct mantle source. On the basis of the sequence of magmatic events obtained from U-Pb zircon ages, we suggest that exotic mega blocks deposited to the WOC basins were related to the Brunovistulicum Terrane. They belong to the group of Vendian/Cambrian granitoids representing the latest, posttectonic expression of the Cadomian cycle.
EN
The Family Kumpanophyllidae Fomichev, 1953, synonymised by Hill (1981) with the Family Aulophyllidae Dybowski, 1873, is emended and accepted as valid. The new concept of this family, based on both new collections and discussion on literature data, confirms the solitary growth form of its type genus Kumpanophyllum Fomichev, 1953. However, several fasciculate colonial taxa, so far assigned to various families, may belong to this family as well. The emended genus Kumpanophyllum forms a widely distributed taxon, present in Eastern and Western Europe and in Asia. Its Serpukhovian and Bashkirian occurrences in China vs Bashkirian occurrences in the Donets Basin and in Spain, may suggest its far-Asiatic origin, but none of the existing taxa can be suggested as ancestral for that genus. Thus, the suborder position of the Kumpanophyllidae remains unknown. Four new species: K. columellatum, K. decessum, K. levis, and K. praecox, three Kumpanophyllum species left in open nomenclature and one offsetting specimen, questionably assigned to the genus, are described.
PL
Utwory jury środkowej na obszarze przedgórza Karpat polskich występują w dwóch rejonach, północno-wschodnim (Księżpol-Nowy Lubliniec-Lubaczów) opracowanym przez autora w 2004 r. i południowym (Wadowice-Busko-Rzeszów), będącym tematem monografii. Jura środkowa rejonu Wadowice-Busko-Rzeszów jest zbudowana głównie z utworów silikoklastycznych o miąższości przekraczającej 300 m, reprezentujących wiek co najmniej od bajosu do keloweju włącznie. W monografii przedstawiono wyniki badań uzyskane w 148 otworach wiertniczych, skorelowanych na podstawie wykresów geofizyki wiertniczej oraz oznaczeń fauny i flory. Szczegółowo omówiono stosunki dotyczące miąższości utworów poszczególnych poziomów środkowojurajskich oraz przedstawiono tektonikę i paleogeografię tych skał. Podkreślono przekraczające ułożenie utworów i transgresywny postęp morza tetydzkiego, stopniowo zwiększającego zasięg i zajmującego coraz większe obszary lądowe.
EN
Middle Jurassic sediments in the Polish Carpathian Foreland occur in two regions: northern (Księżpol-Nowy Lubliniec-Lubaczów) described by Author in 2004 and the southern (Wadowice-Busko-Rzeszów), considered here. The latter contains mainly siliciclastic sediments of thickness exceeding 300 m, whose age range from (at least) Bajocian to Callovian. The study presents results obtained from boreholes, correlated on the basis of logging diagrams and the fauna and flora. The thickness of particular Middle Jurassic series, their tectonics and palaeogeography are discussed in details. The transgressive arrangement of the sediments and the transgressive advance of the Tethyan Ocean, which gradually covered increasingly large areas of land, is evidenced.
EN
In the Polish sector of the Magura Nappe, along the front of the Pieniny Klippen Belt, strongly tectonized calcareous flysch up to 1000 m thick is exposed. Previously these deposits, composed of thin- to thick-bedded flysch, with a packet of Łącko-type marls, have been included into several Paleocene/Eocene formations, e.g., the Szczawnica Formation. This formation contains a poor assemblage of agglutinated foraminifera and a relatively rich assemblage of calcareous nannoplankton, with abundant reworked species. The youngest species give evidence of the NN2 Zone (Lower Miocene). Additionally, in three profiles (Szlachtowa, Knurów and Waksmund) of the Kremna Fm., Early Miocene foraminifera have been recognized. This research documented that during the Burdigalian, at the front of Central Western Carpathians, there still existed a residual marine basin probably up to 100 km wide. These deposits also contain thick packages of exotic carbonate conglomerates derived from the SE, previously regarded as the Jarmuta Formation.
EN
The Early Kimmeridgian succession in the Rogaszyn Quarry at Kodrąb (Radomsko elevation) represents mostly shallow-water carbonate platform deposits that, over wide areas of central Poland were controlled by the activity of the tectonic zone being the prolongation of the Holy Cross lineament. The ammonites collected enable precise recognition of ammonite zones – the Platynota and the Hypselocyclum zones, some subzones and horizons. The precise dating enables detailed correlation of the particular units of the succession with those recognized at the eastern and northern borders of the Wieluń Upland and the NW margin of the Holy Cross Mts. The deposits at Kodrąb from the top of the Planula Zone, through the Platynota Zone, up to the lower part of the Hypselocyclum Zone, reveal markedly smaller thicknesses equaling ~15–20% of those of coeval deposits from the adjoining areas. The differences in sedimentary evolution at Kodrąb during the Early Kimmeridgian resulted mostly from local synsedimentary tectonic movements of fault blocks. Beginning from the late Hypselocyclum Chron, these differences markedly diminished, which resulted from the uniform subsidence of a wider area, and disappearance of the shallow-water deposits of the carbonate platforms, being replaced by deeper-water deposits of the Burzenin Formation.
EN
Litho-, pedo- and palynological analyses constrained by radiometric dating of two loess-palaeosol sequences, Nahirne and Velyka Andrusivka, exposed in a cliff at the eastern edge of the Dnieper Upland, Ukraine, document regional environmental changes in the western marginal zone of the Dnieper lobe. The postglacial loess sedimentation cycle was initiated during MIS 8, immediately after the ice sheet recession. On the basis of palaeorelief analysis, subsequent morphogenetic stages of the original postglacial relief, associated with the modifying and masking role of the loess, and destructive slope processes were reconstructed. Periglacial steppe with consistently present scattered trees formed the Pleistocene landscape in the Middle Dniester area during the last three glacial periods. In such an environment, the following loess beds, correlated with marine isotope stages (MIS), were deposited: Dnieper (dn) - MIS 8, Tyasmyn (ts) - MIS 6, Uday (ud) - MIS 4 and Bug (bg) - MIS 2. During the last two warm periods: Kaydaky (kd) - MIS 7 and Pryluky (pl) - MIS 5, the landscape was not fully forested. As a result, the individual palynological features of these soils show a diverse character. The TL and OSL dates form a sequence with numerous inversions that are difficult to interpret. Although these data do not significantly influence the interpretation, they show that: 1) there are loesses that undoubtedly formed after the maximum extent of the ice sheet by short-distance transport of dust material from local fresh glacial deposits and the underlying Paleogene rocks; 2) date distortions result from the activities of an exceptionally rich pedofauna that has contaminated the material not only in the soil sections of the profile but also in the adjacent loess. It is possible to delimit a few stages of pedofaunal activity in each of the soil units.
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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