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EN
In East Africa and the Arabian Peninsula, Mesozoic and/or Tertiary rift basins are well developed. These rift basins have proven their importance to economic development of the region through major oil discoveries including the Jobi-Rii field in the Albertine basin, Uganda, the Ngamia field in Lokichar Basin, Kenya and the oil fields of Yemen. The Main Ethiopian Rift (MER) developed during the Oligocene-Miocene time as part of the East African Rift System and is commonly divided into the Northern, Central and Southern parts. The subsurface rift architecture of the MER remains poorly understood due to lack detailed geophysical studies. This study aims to investigate the subsurface stratigraphic and structural setup of the Southern MER by using 2D high-resolution seismic reflection surveys integrated with nearby well data. Analysis of 2D-seismic reflection data in the Southern MER reveals four horizons from which three horizons show good correlations in Northern Abaya and Gelana basins. The basement structure delineated the main basins in the study area: Northern Abaya, Southern Abaya, Chamo and Gelana sub-basins. The sub-basins showed a typical rift-basin development: pre-rift, syn-rift and post-rift sedimentation and the faulted basement is dominantly oriented NE-SW parallel to the regional structural trend of the area. The deepest basement is greater than 3600 m in Northern Abaya basin followed by Gelana Basin which reaches to 3100 m. Southern Abaya and Chamo basins have shallow basement depths less than 2250 m. Interpretation of the interval velocity integrated with the geology and nearby well data helped to identify the different stratigraphic units ranging from Jurassic to Quaternary time span in the area. Possible source rocks of Late Jurassic to Upper Cretaceous marine shales and fluvial-lacustrine sediments of Lower Miocene thickness 1200 m and 1800 m are identified in Northern Abaya Basin, respectively, where the thicknesses of those units are 900 m and 1000 m in Galena Basin. We also infer from seismic interpretation that the upper Miocene sand/sandstone inferred on both sub-basins can be considered as a reservoir, whereas distinctive fault closures against the basement with horst and grabens or tilted half grabens and anticlinal structures can smoothly provide the hydrocarbon trapping mechanism. Numerous faults mapped on seismic sections play a major role for migration of hydrocarbon from source to reservoir rocks. The interpreted NE-SW major faults located on the western side of most of the seismic sections reactivated during the East African rifting at Neogene period produced an appreciable throw which can also provide migration pathways for the hydrocarbon.
PL
Pod posadzką kościoła św. Elżbiety we Wrocławiu znajduje się pomieszczenie stanowiące zabezpieczony wykop archeologiczny. Powstało ono w końcu XX wieku w celu ekspozycji reliktów poprzedniego kościoła odkrytych w 1976 roku. Plany te nie zostały zrealizowane, a krypta nigdy nie pełniła funkcji ekspozycyjnej. Dla badań architektonicznych stanowi jednak kluczowy punkt kościoła. Położenie w jego centralnej części pozwalana dostęp do reliktów świątyni z XIII wieku oraz pozostałości po przebudowach kościoła w okresie średniowiecza i nowożytności – aż do końca XX wieku. Jako taka została w latach 2021–2022 zinwentaryzowana oraz przebadana metodą stratygraficzną. W efekcie powstało kompletne rozwarstwienie chronologiczne krypty. Wydzielono siedem faz budowlanych składających się na zapis całej historii kościoła. Umożliwiło to próbę rekonstrukcji dziejów kościoła późnoromańskiego oraz niektórych partii istniejącego.
EN
Underneath the floor of St. Elizabeth’s Church inWrocław is a room that is a secured archaeological excavation. It was created at the end of the twentieth century to display the relics of the former church discovered in1976. These plans were not implemented and the cryp twas never used as an exhibition space. For architectural research, however, it represents a key point in the church. Its location in its central part allows access to the relics of the thirteenth-century church, as well as there mains of the church’s alterations in the medieval and early modern periods—up to the end of the twentieth century. As such, it was inventoried in 2021–2022 and surveyed using the stratigraphic method. The result was a complete chronological stratification of the crypt. Seven construction phases were separated, making up the record of the entire history of the church. This enabled an attempt to reconstruct the history of the late Romanesque church and some parts of the existing one.
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
A novel stratigraphical scheme within the Folge Concept is described for the Cenomanian Chalk of England that is particularly suitable for investigating the regional changes in the lithofacies, diagenesis, geochemistry, and mineralogy of the sediments of the Chalk Sea leading up to the Cenomanian–Turonian Oceanic Anoxic Event. It is based on “isochronous” marker bands defined largely by calcitic macrofossil assemblages, and it avoids problems caused by the poor or non-preservation of ammonite assemblages and lateral changes in chalk lithofacies. Eight folgen are based on one, two, or more marker bands. Their sequences, lithologies and calcitic macrofossil assemblages are described from 33 exposures in the Northern Chalk Province of England. The folgen are named, in ascending order, the Belchford, Stenigot, Dalby, Bigby, Candlesby, Nettleton, Louth and Flixton, after villages in Lincolnshire and Yorkshire, England. The folgen are traced throughout the Transitional and Southern Chalk provinces of England. They are present in the Cenomanian chalk of northern Germany and northwest France. Regionally, an individual folge may display considerable vertical and lateral variation in general lithology and lithofacies whilst still maintaining their defining marker bands. The possibility of further refinement to the scheme is discussed.
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
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.
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.
EN
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.
19
Content available remote Analiza przyczyn powstania liniowej deformacji nieciągłej
PL
W artykule przedstawiony został przykład wystąpienia na powierzchni liniowej deformacji nieciągłej powyżej przecznic polowych, jednej z kopalń GZW. Przeprowadzona została analiza warunków geologiczno-górniczych wraz z obliczeniami deformacji powierzchni wywołanymi dokonaną eksploatacją.
EN
The article presents an example of the occurrence of a discontinuous deformation on the surface above the field cross-cuts, in one of the mines of Upper Silesian Coalbasin. The analysis of geological and mining conditions was carried out along with calculations of surface deformations caused by the performed mining operations
EN
At its maximum development in the type area on the Devon coast, the Upper Greensand Formation comprises up to 55 m of sandstones and calcarenites with laterally and stratigraphically variable amounts of carbonate cement, glauconite and chert that were deposited in fully marine, shallow-water environments. The formation is divided into three members, in ascending order the Foxmould, Whitecliff Chert and Bindon Sandstone, each of which is bounded by a prominent erosion surface that can be recognised throughout the western part of the Wessex Basin. The full thickness of the formation, up to 60 m, was formerly well exposed in cliffs in the Isle of Purbeck in the steeply dipping limb of the Purbeck Monocline. The upper part of the succession is highly condensed in comparison with the Devon succession and exhibits lateral variations over distances of hundreds of metres that are probably related to penecontemporaneous fault movements. Much of the fauna is not age-diagnostic with the result that the ages of parts of the succession are still poorly known. However, the Isle of Purbeck sections contain diverse ammonite faunas at a few stratigraphically well-defined levels that enable the succession to be correlated with that of east Devon and west Dorset.
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