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EN
The study of the Tithonian and lower Berriasian succession of Le Saix (Hautes-Alpes, France) has made it possible to better characterize the lithological succession at a former Berriasian GSSP candidate, its set of microfacies, the stratigraphic ranges of the main groups of marine plankton and therefore the calpionellid and saccocomid biozonations. On the lithological level, the Tithonian strata are characterized by thick-bedded breccias representing debris flows and related calciturbidites, whereas the Berriasian strata are typically white limestones. The lower part of the Berriasian is comprised of scattered intercalations of thin-bedded breccias and calciturbitides (including cryptic mud calciturbidites). In thin sections, the white limestones display mud- to wackestone textures and their allochems are mostly tiny bioclasts (e.g., radiolarians, calpionellids, saccocomids). Calciturbidites have wacke- to grainstone textures and their allochems are mostly pseudointraclasts and extraclasts, comprising various bioclasts and some ooids. Mud turbidites are made of micrograin-stones some yielding almost exclusively well-sorted calpionellids, which were previously erroneously interpreted as the signature of “explosions” or “blooms” of Calpionella alpina. Breccias are mostly lithoclastic floatstones with a matrix similar to that of the calciturbid- ites. Their lithoclasts are either extraclasts sensu stricto, i.e., material derived from updip shallow-water areas, or pseudointraclasts representing reworked subautochthonous material, i.e., mud- and wackestone lithoclasts with radiolarians, saccocomids and/or calpionellids. Radiolarians are common over the whole studied interval. Saccocomids are part of the dominating biota reported from the lower and lower upper Tithonian interval whereas calpionellids replace them in the uppermost Tithonian to lower Berriasian interval. Minor plank- tonic groups comprise calcareous dinoflagellates and Globochaete alpina; Iranopsis nov. group is also present. Intervals with saccocomid sections characteristic of zones 4-5 and zone 6 are respectively ascribed here to the lower Tithonian (4-5) and the lower upper Tithonian (6). The biozonation of the calpionellid group sensu lato allows identification of i) the Boneti Subzone of the chitinoidellids, ii) the Cras- sicollaria Zone, more specifically its Tintinnopsella-Intermedia (A1), Intermedia-Alpina (A2) and Brevis-Massutiniana (A3) subzones, and iii) the Alpina Zone, with its Alpina-Parvula (B1) and its Alpina-Remaniella (B2) subzones. On the basis of biostratigraphical and sedimentological data, most zonal boundaries prove to be hiatal, located at the erosional base of breccia or turbidite layers whereas the Tithonian/Berriasian stage boundary appears to be located at a strike-slip fault plane in the Tré Maroua section.
EN
There are several thrust sheets in the Lesser Himalayan region of Nepal. The Jajarkot nappe is one of them. It is located immediately west of the Kahun Klippe and east of the Karnali Nappe. There is no unified stratigraphy established for this thrust sheet. In the present research, an attempt was made to establish the stratigraphy of the Jajarkot nappe to fulfill the research gap. Previously described by Fuchs & Frank (1970) and Sharma (1980), the Jajarkot nappe in western Nepal have two distinctive crystalline lithological units: the Chaurjhari Formation and Thabang Formation. The previous unit consists of garnet-grade schist, and quartzites, with intrusions of basic rocks and granites, while the later unit consists of grey to brown crystalline limestones with biotite-quartz-schists. An unconformity is observed above the Thabang Formation. The younger geological unit above the unconformity is mapped as the Jaljala Formation, which is composed of finegrained calcareous sandstone and calcareous siltstone with minor proportions of limestones and grey-green slates. At present work, a preliminary geological study was carried out to work on the stratigraphy of the Jajarkot nappe in the Jaljala areas at 1:25,000 scales. Fossils of crinoids are found in the rock unit of the Jaljala Formation. These fossils are considered the index fossils of the Silurian. In this case, the Jaljala Formation would be equivalent to the rocks of the Tethyan affinity, and further study is under progress. The concept that the thrust sheets are moved from north to south in the Himalayas will be evidenced by these findings. An attempt is made to correlate the presently found fossils with the crinoids of the Phulchauki Group of the Kathmandu nappe and with the root zone of the Tethys succession.
EN
The Belqa Group of Jordan (Upper Cretaceous–Eocene) contains a remarkable succession of sedimentary lithofacies, including chalk, sandstone, chert, phosphorite, oyster mounds and organic-rich marls deposited along the passive southern margin of the Neo-Tethys Ocean. The Belqa Group is now outcropping in spectacular wadis where they can be studied in detail. The exceptional outcrops exposures provide unique opportunities for studying three-dimensional spatial facies variations. However, this 3D facies distribution requires robust time control and the combination of modern sequence stratigraphic concepts and high-resolution dating methods. We report the establishment of a regional sequence stratigraphic model that provides the temporal framework for further detailed sedimentological, palaeontological and geochemical studies. Preliminary results show a stratigraphic organization in four major depositional sequences (3rd order), which are broadly in agreement with the lithostratigraphic formations. The age dating is based on new nano-fossil analyses and C/O and Sr isotope stratigraphy. A subdivision into higher-frequency sequences (4th/5th order) significatively improves the resolution of the stratigraphic framework and our understanding of spatio-temporal distribution of the sedimentary facies. The four sequences are: 1) The B1 sequence (Upper Coniacian-Santonian), characterized by a transgressive phase of chalk-rich sedimentation (coccolithophore-dominated) and a regressive phase of a prograding siliciclastics with a distal transition to the first phosphorite-chert facies. 2) The B2 sequence (Lower Campanian) also starts with a transgressive chalk dominated facies and subsequently develops into a chert-dominated marl facies (radiolarian-dominated). The chert is locally associated with thin phosphates and coquinas, as well as organic-matter rich facies in proximal marine settings. 3) The B3 sequence (Upper Campanian) is also characterized by a transgressive chalk dominated facies. The regressive phase is constituted by dm- to m-thick phosphorite beds that were deposited coevally with giant oyster banks (decameter scale). 4) The B4 sequence (Maastrichtian-Paleocene) represents a dramatic facies change to organic-rich pelagic marls, and can probably be further subdivided. This sedimentary succession highlights both gradual and rapid changes in biogenic productivity and geochemistry. These changes are punctuated and partly driven by significant relative sea-level changes, and likely also larger scale palaeoceanographical processes that are the focus of future work.
EN
The south-western part of the Gorce Mts (Outer Carpathians) is composed of flysch deposits of the Krynica and Bystrica subunits of the Magura Nappe. The Krynica Subunit includes the Late Cretaceous–Paleocene Ropianka Fm, the Early Eocene Beloveža Fm, the Early Eocene–Oligocene Magura Fm and the Oligocene–Early Miocene Malcov Fm, while the Bystrica Subunit includes the Middle Eocene–?Oligocene Magura Fm, represented mainly by the thick-bedded Magura Sandstone. Thin- and medium-bedded sandstone-shale turbidites predominate in the other formations. The lithostratigraphic units are dated on the basis of foraminifers. The studied deposits accumulated in the southern part of the Magura Basin. Their detrital material was derived from a ridge, bounding the basin in the south. In the study area, the Krynica Subunit overthrusts the Bystrica Subunit. The studied deposits are folded, thrust and cut by numerous faults. The Turbacz Thrust Sheet and the newly identified Kudłoń Thrust Sheet were distinguished in the Krynica Subunit. Faults of different lengths and throws are transverse or oblique. Some of them form complex dislocation zones with lengths of up to several km. In general, the high-resolution digital elevation model DEM contributed significantly to progress in the geological and geomorphological research.
EN
The article tried to prove that in architectural research we will use two-dimensional linear drawings for some time. The considerations were based on materials from research conducted in 2017–2022. Most of them are studies made under the author’s direction by a team consisting of doctoral students and students of the Faculty of Architecture of the Wrocław University of Science and Technology. The summary states that in scientific research the basis of the message should be communicativeness and understandable publication of intermediate stages of research. In this case, avery good form of presenting indirect analyses is a two-dimensional recordingof stratigraphy. To facilitate this, the term “architectural stratigraphic unit” was introduced. Such a unit includes all architectural elements – both the building material and other parts of the building. The basic criterion for determining one architectural unit is the simultaneity of the formation of components.
PL
W artykule starano się udowodnić, że w badaniach architektonicznych jeszcze przez pewien czas będziemy wykorzystywać dwuwymiarowe rysunki linearne. Podstawą rozważań były materiały z badań prowadzonych w latach 2017–2022. Większość z nich to opracowania wykonane pod kierunkiem autorki przez zespół złożony z doktorantów i studentów Wydziału Architektury Politechniki Wrocławskiej. W podsumowaniu stwierdzono, że w badaniach naukowych podstawą przekazu powinna być komunikatywność i zrozumiałe publikowanie pośrednich etapów badań. W tym przypadku bardzo dobrą formą zaprezentowania analiz pośrednich jest dwuwymiarowa rejestracja stratygrafii. Aby to ułatwić, wprowadzono pojęcie „architektoniczna jednostka stratygraficzna”. W skład takiej jednostki wchodzą wszystkie elementy architektoniczne – zarówno budulec, jak i inne części budowli. Podstawowym kryterium określania jednej jednostki architektonicznej jest równoczesność powstawania składowych.
EN
The middle and upper parts of the Skały Fm, Early to Middle Givetian in age, were investigated in four sections at Miłoszów Wood in the Łysogóry Region (northern region of the Holy Cross Mountains, central Poland). The dating is based on conodonts (Polygnathus timorensis Zone to the later part of the Polygnathus varcus/Polygnathus rhenanus Zone; early Polygnathus ansatus Zone cannot be excluded) and spores (Ex1–2 subzones) and, coupled with cartographic analysis and geophysical investigation, allows correlation within the strongly faulted succession. Significant lateral facies variations within the carbonate ramp depositional system in comparison with the better studied Grzegorzowice–Skały section, about 3 km distant, are documented, thanks to conodont-based correlation of both successions. Foraminifers, fungi, sponges, rugose and tabulate corals, medusozoans, microconchids and cornulitids, polychaetes (scolecodonts), molluscs (bivalves, rostroconchs, and gastropods), arthropods (trilobites and ostracods), bryozoans, hederelloids, ascodictyids, brachiopods, echinoderms (mostly crinoids, rare echinoids, holuthurians, and ophiocistoids), conodonts, fish, plants (prasinophytes, chlorophycophytes, and land plant spores), and acritarchs are present. Brachiopods are the most diverse phylum present (68 species), other richly represented groups are bryozoans and echinoderms; in contrast, cephalopods and trilobites are low in diversity and abundance. The muddy, middle to outer ramp biota (200 marine taxa, including 170 species of marine animals, 22 photoautotrophs, 6 forams) represents a mixture of allochthonous shallower-water communities (upper BA3), including storm- and possibly tsunami-affected coral mounds, and autochthonous deep-water soft-bottom brachiopod (e.g., Bifida–Echinocoelia) communities (BA 4–5). The richness and diversity of the Miłoszów biota is relatively high, comparable with other approximately coeval pre-Taghanic ecosystems during the Devonian climatic deterioration (cooling). Preliminary data indicate that in the Holy Cross Mountains, no large-scale replacement of brachiopod (and probably many other benthic ones, like crinoids) communities took place between the Early–Middle Givetian and the Early Frasnian, in contrast to the demise of the Hamilton/Upper Tully fauna in the Appalachian Basin. Such a similarity of pre- and post-Taghanic faunas does not exclude the occurrence of environmental perturbations and transient community turnovers, caused by immigrations during the Taghanic Biocrisis, but evidences the successful recovery of the indigenous biota.
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 stratigraphic division of the Saalian (Middle Pleistocene) in Europe, the Wartanian cold period has the rank of a stadial of the Odranian Glaciation, correlated with MIS 6. The authors demonstrate the higher rank of this cold period, on the basis of an analysis of the sedimentary succession in eastern Poland, at an exposure of the terminal moraine of the Wartanian ice sheet. At the Wólka Zagórna site, three stratigraphic units were distinguished: A (lower glacigenic deposits – glaciofluvial deposits and subglacial till), A/B (fossil soil of lessivé type), B and C (a periglacial horizon with deflation pavement, involutions, frost-wedge structures and upper glaciofluvial deposits and flow till, with ice-wedge casts). Two distinct periods of climatic cooling, associated with the youngest Saalian ice sheets, were recorded in this succession in E Poland: Odranian (unit A, an ice-sheet transgression marked by the deposition of glaciofluvial deposits dated as 365–226 ka, ending with the deposition of subglacial till), and Wartanian (units B and C, an ice sheet transgression marked by development of a periglacial zone, dated as 180–126 ka, and then deposition of glacigenic sediments at the front of the ice sheet and formation of a marginal moraine). Each of these periods of ice-sheet transgression occurred at a different time (in the MIS 8 and MIS 6 positions) and were separated by a warm period. It is documented by unit A/B – a fossil soil with a very well developed Bt horizon – which attests to its formation in an illuviation process beneath a complex of mixed forests during an interstadial warming that occurred in MIS 7. From this palaeoclimatic reconstruction, it is inferred that the Wartanian cold period should be viewed as a separate glaciation in MIS 6 and the Odranian period should be assigned to MIS 8 in the stratigraphic schema of the Quaternary.
EN
In Butkov Quarry, ammonites of the families Holcodiscidae Spath, 1923 and Barremitidae Breskovski, 1977 occur in the pelagic Lower Cretaceous pelagic deposits of the Manín Unit. This contribution discusses the taxonomy of both families and presents their distribution in the layered sequences of the quarry. The genus Spitidiscus Kilian, 1910 classified as a member of the Superfamily Perisphinctoidea Steinmann in Steinmann and Döderlein, 1890 is an important representative of the Holcodiscidae from a stratigraphic point of view. In areas where the zonal index Acanthodiscus radiatus (Bruguière, 1789) does not occur, as in Butkov Quarry, the first representatives of Spitidiscus indicate the base of the Hauterivian. The genus Plesiospitidiscus Breistroffer, 1947 was long regarded as a member of the Superfamily Desmoceratoidea Zittel, 1895. This superfamily was based on its type species, Eodesmoceras celestini (Pictet and Campiche, 1860), which is not Valanginian in age, as now clearly proven. As a consequence, this superfamily is considered invalid. Vermeulen and Lahondère (2011) proposed an alternative by selecting a suitable initial genus, namely Plesiospitidiscus, for the Family Barremitidae, Superfamily Barremitoidea Breskovski, 1977 (nom. transl. Vermeulen and Lahondère, 2011).
EN
The Lower Devonian (Emsian) and Middle Devonian of Belarus contain assemblages of biostratigraphically useful faunal and floral microremains. Surface deposits are few, with most material being derived from borehole cores. Acanthodian scales are particularly numerous and comparison with scales from other regions of the Old Red Sandstone continent (Laurussia), specifically the Orcadian Basin of Scotland, the Baltic Region, Spitsbergen, and Severnaya Zemlya have demonstrated a lot of synonymy of acanthodian species between these areas. This is especially the case between Belarus, the Orcadian Basin and the Baltic Region, which has allowed us to produce an interregional biostratigraphic scheme, as well as to postulate marine connection routes between these areas. The acanthodian biostratigraphy of Belarus is particularly important as it is associated with spores and marine invertebrates, so giving the potential of more detailed correlations across not only the Old Red Sandstone continent, but elsewhere in the Devonian world. We also demonstrate that differences in preservation (e.g., wear and how articulated a specimen is) is one of the main reasons for synonymy.
11
Content available remote Seismic attribute analysis of Chicxulub impact crater
EN
Chicxulub crater formed~66 Ma ago by an asteroid impact on the Yucatan platform in the southern Gulf of Mexico. The crater has a ~ 200 km rim diameter and has been covered by carbonate sediments up to ~ 1.1 km thick in the central zone. Previous studies have identifed the structure and major crater units through geophysical models from seismic refection and potential feld data, classifed as the central uplift, terrace zone, outer and inner ring fault zones and impactite deposits. Impact produced a deep excavation cavity, with fragmentation and ejection of large volumes of crustal target rocks. Understanding the pre-existing structures, impact-induced deformation and post-impact processes requires high-resolution images of the crater and target zone. For this study, we use complex trace attributes of instantaneous phase, frequency, envelope amplitude and similarity, in an E-W seismic refection profle crossing the crater in the marine sector. Geophysical logs and borehole lithological columns from the on-land drilling projects are used to constrain the petrophysical analysis. Seismic attributes aid to characterize the radial fault zones and physical property contrasts, revealing asymmetries in the crater structure. The refector packages in the post-impact sediments and target Cretaceous sequence are identifed in the frequency and phase attributes. The bottom crater refectors, with the basal sediments flling the crater foor topography, are enhanced with the envelope amplitude attribute. A set of high-amplitude refectors is shown in the similarity attribute, in which the refector geometry is delineated on the target carbonate sequence. The ofsets in the high-amplitude refectors between the eastern and western sectors are possibly associated to target pre-impact asymmetries, impact deformation and efects of central crater collapse.
EN
The subsurface groundwater potential was calculated through the Geographic Information System (GIS) tool in district Jamshoro, Sindh, Pakistan; research was carried out in the vulnerable and arid climatic regions of the study area, which experienced unpredictable droughts and extreme foods. The primary recharging source of the aquifer is rainfall only in monsoon season from July to September. The current situation of water resources is critical in the region; in the present research work, two principal groundwater aquifers were encountered present in lithology of Laki formation mostly in sand and gravel lithology, which are shallow and deep aquifers. The GIS has been employed as a preservative tool to estimate groundwater potential. The estimated groundwater potential was 29,330.22 million cubic meter (MCM) under the monitoring area of 3207.25 square kilometers (km²); thus, the volume of groundwater was 9.14 MCM/km² in the selected cluster zone of the study area. It is realized that using a GIS tool combats the susceptible situation and shows authenticated results of groundwater potential.
EN
During the late Oligocene to early Miocene the residual Magura Basin was located along the front of the Pieniny Klippen Belt (PKB). This basin was supplied with clastic material derived from a south-eastern direction. In the Małe (Little) Pieniny Mts. in Poland, the late Oligocene/early Miocene Kremna Fm. of the Magura Nappe (Krynica subunit) occurs both in front of the PKB as well as in the tectonic windows within the PKB. Lenses of exotic conglomerates in the Kremna Fm. contain frequent clasts of Mesozoic limestones (e.g. limestones with “filaments” microfacies and Urgonian limestones) and Eocene shallow-water limestones. Fragments of crystalline and volcanic rocks occur subordinately. The provenance of these exotic rocks could be probably connected with Eocene exhumation and erosion of the SE part of the Dacia and Tisza Mega-Units.
EN
Detailed study of all the ammonite collections gathered by the authors in the Staffin Bay sections has resulted in minor changes in the distribution of ammonite taxa, and slight modification of the position of the Oxfordian/Kimmeridgian boundary. Most significant is the discovery of Pictonia (Triozites) cf. seminudata which results in the placing of the stage boundary 0.16 m below the level formerly proposed. This study discusses the evolution of the Subboreal family Aulacostephanidae, and the Boreal family Cardioceratidae, indicating changes in the patterns of individual development in the evolution of both families in terms of heterochrony. The Oxfordian/ Kimmeridgian boundary interval shows major morphological changes in both ammonite families which were released from phylogenetic constraints by heterochrony, closely related to changes in environmental conditions.
EN
The present study revolves around the identification of the stratigraphical boundary between Pleistocene formations that formed prior to the first advance of the Scandinavian ice sheet (Early Pleistocene, i.e., the so-called preglacial) and the overlying, glacially derived deposits (Middle Pleistocene). In particular, it focuses on variation in heavy mineral assemblages, which are an important tool for stratigraphers. The Neogene basement, described here, was most often the source of material that was redeposited by Early Pleistocene rivers. The geological structure and Early Pleistocene palaeogeographical scenarios for various Polish regions are discussed. Moreover, comparisons with other European preglacial formations are carried out. The mineral spectrum of Lower Pleistocene deposits is largely dependent of rocks of the Neogene and Mesozoic basement. If the incision of ancient catchments was into terrigenous rocks, the stratigraphical boundary between preglacial and glacial formations is easily determined with the help of a heavy mineral analysis. As a rule, this coincides with a noticeable change from resistant to non-resistant mineral associations. Such cases are noted for successions in central Poland and eastern England. On the other hand, outcrops of igneous or metamorphic rocks exist within preglacial river catchments in most parts of Europe. They were the local sources of non-resistant heavy minerals long before their glacial supply from the Baltic Shield. In these cases, mineralogical analysis fails in the search for the Early/Middle Pleistocene transition.
EN
The study was carried out in the wall of a cliff that formed as a result of erosional cutting in the western foreland of a moraine landform from the Pomeranian and Gardno phases (Upper Plenivistulian, Rowy-Ustka clifs; northern Poland). Individual lithostratigraphic units have been documented: glaciofluvial delta deposlts, Poddąbie Till, lacustrine-glacial Wytowno Formation (consisting of three facies: deltaic, lower diamicton, and upper diamicton), lacustrine deposits of the Orzechowo Formation with a thick peat layer, and aeolian series at the cliff crest. The Wytowno Formation deposits include the following lithologies: medium-grained sands, fine-grained sands, muddy sands, muds, silty clays, clays, varved clays, fine-grained multi-fraction deposits, and tills (Dębina Till). Very high inclination of the strata is the result of glaciodynamic deformation. The deposits were accumulated in a proglacial lake. They are characterized by mud and clay as well as sand and sand-muddy lithofacies. The vastness of the water body is evidenced by a considerable size of the delta, and by massive structures of the clay layers.
PL
W artykule przedstawiono problemy związane z należącym do procesu badań powierzchni architektonicznych odsłanianiem malowideł ściennych. Omówiono też sposób przygotowywania w przeszłości wtórnych powłok przed nanoszeniem kolejnych dekoracji oraz podstawowe zasady postępowania konserwatorskiego. Warstwy stratygraficzne malarstwa ściennego stanowią: murowane podłoże, tynki, pobiały i warstwy barwne. Nie zawsze zdejmowane są wszystkie wtórne nawarstwienia z całej powierzchni oryginalnej dekoracji, czasami wykonuje się jedynie niewielkie odkrywki. Zdejmowanie przemalowań jest prowadzone w ramach prac konserwatorskich, dlatego duża część rozstrzygnięć należy do specjalistów z tej dziedziny. W przeszłości konserwatorzy odsłaniali zwykle w całości zachowaną warstwę najstarszą; późniejsze były po prostu tracone. Dziś istnieje wiele metod konserwacji i sposobów ekspozycji, aby ocalić malowidła pochodzące z kilku okresów historycznych, stworzone na tej samej ścianie. Różne sposoby i formy ich ekspozycji pokazano w artykule na fotografiach. Należy podkreślić, że jednoczesna prezentacja malowideł pochodzących z kilku okresów to głównie kwestia estetyczna. Nie wolno też zapominać, że dekoracja malarska nie tylko jest dziełem sztuki, ale stanowi dokument losów historycznej budowli.
EN
The article presents problems of revealing of mural paintings which is an integral part of architectural surfaces investigation. The paper also describes different kinds of preparatory layers used in the past as a support for new decorations and general rules of its conservation proceedings. The stratigraphic layers of mural painting are the following: the wall, plasters and renderings, strata of whitewash and polychromes. In some cases only limited parts of authentic paint are presented without removing of all layers added later on the whole decorated surface. Overpaintings are removed in conservation treatment, that is why the conservator is the one to make the most important decisions. In the past conservators used to reveal the oldest existing paint layer; overlapping layers were simply lost. Today there are many solutions and methods of conservation allowing to preserve and expose paintings created on the same wall in different historical periods. The photographs included in the article illustrate different systems and forms of presentation. It should be stressed that parallel presentation of paintings coming from several periods is mainly an aesthetical problem. One should also remember that painted decoration is not only a work of art but also a document of history of the building.
EN
The Upper Greensand Formation, mostly capped by the Chalk, crops out on the edges of a broad, dissected plateau in Devon, west Dorset and south Somerset and has an almost continuous outcrop that runs from the Isle of Purbeck to the Vale of Wardour in south Wiltshire. The Formation is well exposed in cliffs in east Devon and the Isle of Purbeck, but is poorly exposed inland. It comprises sandstones and calcarenites with laterally and stratigraphically variable amounts of carbonate cement, glauconite and chert. The sedimentology and palaeontology indicate deposition in marginal marine-shelf environments that were at times subject to strong tidal and wave-generated currents. The formation of the Upper Greensand successions in the region was influenced by penecontemporaneous movements on major fault zones, some of which are sited over E-W trending Variscan thrusts in the basement rocks and, locally, on minor faults. Comparison of the principal sedimentary breaks in the succession with the sequence boundaries derived from world-wide sea-level curves suggests that local tectonic events mask the effects of any eustatic changes in sea level. The preserved fauna is unevenly distributed, both laterally and stratigraphically. Bivalves, gastropods and echinoids are common at some horizons but are not age-diagnostic. Ammonites are common at a few stratigraphically narrowly defined horizons, but are rare or absent throughout most of the succession. As a result, the age of parts of the succession is still poorly known.
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The sedimentological and lithostratigraphic record from north-central Bir Tarfawi documents the presence of Pleistocene basin-fill deposits. Three topographic basins were created as a result of deflation during climate episodes associated with lowering of the local groundwater table. In each case, the three deflational basins or topographic depressions were subsequently filled with sediments; these basin aggradations coincided with changes from arid climate conditions to wetter conditions and a rise in the groundwater table. The oldest and highest sedimentary remnant is associated with Acheulian artifacts and may reflect spring-fed pond and marsh conditions during a Middle Pleistocene wet climate episode. Lithofacies for a lower stratigraphic sequence (the “White Lake”) documents deposition in a perennial lake that varied in extent and depth and is associated with Middle Paleolithic artifacts. A third episode of deflation created a topographic low that has been filled with Late Pleistocene sediments that are associated with Middle Paleolithic artifacts and fossil remains. Lateral and vertical variations in the lithofacies of this basin-fill sequence and the sediments of the “grey-green” lake phases provide a record of changing hydrologic conditions. These hydrologic conditions appear to reflect variations in water-table levels related to groundwater recharge and, at times, local rains.
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The major goal of the project “The evolution of terrestrial environments of the Upper Silesian Keuper as biotopes of vertebrates”, granted for Grzegorz Racki by the Ministry of Science and Higher Education (2009-2013), was an exhaustive, integrated study of the bone-enriched middle Keuper interval in terms of stratigraphy, sedimentology, mineralogy and geochemistry. The new website “Bone-bearing Keuper of the Upper Silesia, southern Poland” (http://www.ing.pan.pl/Keuper/Bone-bearing_Keuper-1.htm)presents in English the results of this project. The significant achievements are only a starting point to a comprehensive presentation of the complex Keuper themes, jointly with an extensive repository of regional literature (above 420 full-texted publications since 1790). In addition, the main results of the grant, as well as diversity of their implications for future studies are summarized herein, with emphasis on controversial geochronological aspects in vertebrate paleontology (how many bone-rich levels?), and in a broad historical context.
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