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EN
The Aucellina biostratigraphy of the Upper Albian Kirchrode Marls Member succession in the Kirchrode I (1/91) cored borehole is described and the fauna illustrated. The borehole commenced at an unknown depth below the Early Cenomanian marls of the Bemerode Member, but higher beds of the Kirchrode Marls and the basal beds of the Bemerode Member were exposed in the Mittellandkanal and its Stichkanal extension at Misburg. The borehole and surface exposures permit a virtually complete Late Albian succession of Aucellina species to be observed. Published Aucellina range data from the borehole are reassessed and it is suggested that the lower part of the recorded range is based partly on misidentifications of fragments of thin-shelled bivalves such as Syncyclonema and Amussium. Aucellina appears in the borehole succession within the upper part of the Callihoplites auritus ammonite Subzone (Mortoniceras inflatum Zone) and continues to the top of the borehole succession within the Preaeschloenbachia briacensis ammonite Subzone (Stoliczkaia spp. Zone). Aucellina from higher in the briacensis Subzone collected from the Misburg Mittellandkanal section are also discussed and illustrated. There is some evidence that Aucellina occurs typically at levels in the borehole containing predominantly Boreal European Province ammonites, supporting the general inference that Aucellina lived in cooler northern waters. In contrast, Aucellina is poorly represented in intervals with Tethyan ammonites and thin-shelled inoceramids (e.g. the Mortoniceras (Durnovarites) perinflatum Subzone, Stoliczkaia spp. Zone). The briacensis Subzone, with an admixture of Tethyan (Stoliczkaia) and Boreal ammonites contains a distinctive, taxonomically highly diverse Aucellina assemblage. Relevant taxonomic research on European Late Albian and Early Cenomanian Aucellina faunas is reviewed. The Late Albian Aucellina succession in the borehole differs from that established from partially correlative successions in England.
EN
The geological position and geochemistry of the basaltic sill and tuffs occurring within the Berriasian–?Albian pelagic limestones of the Czorsztyn Succession are described. The volcanic rock succession of the Velykyi (= Veliky) Kamenets’/Vilkhivchyk (= Vulkhovchik, Vulhovchik, Olkhivchyk) sites is related to intra-plate submarine volcanism, which took place at the southeastern termination of the Pieniny Klippen Belt. This volcanism was probably associated with the Early Cretaceous opening of the Magura/Fore-Magura basinal system, bounded by the Silesian/Marmarosh and Czorsztyn palaeoridges to the north and south respectively. The alkaline volcanic rocks from the Velykyi Kamenets’/Vilkhivchyk sites are geochemically similary to the basaltic block from Biała Woda (Małe Pieniny Mts., Poland), which is an olistolith a few metres across within the Jarmuta conglomerates (Maastrichtian/Paleocene). This basaltic block was eroded from the frontal part of the Czorsztyn Nappe and was deposited in the uppermost part of the Grajcarek Succession at the southeastern margin of the Magura Basin.
EN
The present study establishes a lithostratigraphic subdivision, a bio- and chemostratigraphy and describes the sedimentology of the Alstatte Bay at the southern margin of the Lower Saxony Basin in northern Germany. The socalled Fischschiefer is developed in the lower part of the section, a 2.1 m thick laminated interval that shows TOC values of up to 2 % and is interpreted as local expression of the global Oceanic Anoxic Event 1a (OAE 1a). The basal part of the Fischschiefer is fairly continuously laminated, whereas its upper part is characterized by an alternation of laminated and non-laminated beds. Stable carbon isotopes ([delta^13]C[carb]) show a characteristic pattern for the Fischschiefer interval that can be correlated with sections from the Tethyan Realm. Immediately above the Fischschiefer, however, the studied section might reveal a diagenetic overprint as indicated by very negative carbon stable isotope values. The remaining part of the section is characterized by a rather monotonous claystone succession, terminated by a greenish layer rich in glauconite overlain by glacial till of Pleistocene age. The fauna is typically Boreal in the lower part of the section, but changes around 2 m above the Fischschiefer towards an assemblage indicating a distinct Tethyan influx. The faunal shift is considered to be due to the maximum flooding of the continuous, long-term sea level rise of the Early Aptian which led also to a supposed shift from a restricted to open bay environment.
EN
The proto-Silesian Basin was well developed within the Alpine Tethys during the Late Jurassic times and existed as undivided entity until the significant Late Cretaceous reorganization. The deposits originated within this basin were incorporated into different structural units: Silesian, Subsilesian and Skole. The calciturbiditic Cieszyn Limestone Formation is the oldest Cretaceous flischoidal sequence of the proto-Silesian Basin. This calciturbiditic sedimentation passed gradually into younger siliciclastic deposition.
EN
Sedimentological development of the Verovice Formation (Czech Moravia) is presented, according to Early Cretaceous geotectonic-eustatic changes in the proto-Silesian Basin. Those processes were a consequence of a gradual rebuilding the architecture of the Alpine-Carpathian realm. The geological events well correspond with the global sequence stratigraphy.
PL
Jednym z celów prężnie rozwijającej się w ostatnich latach geoturystyki jest propagowanie aspektów poznawczych związanych z geologiczną historią Ziemi. W niniejszej pracy zostały zawarte opisy klasycznych polskich stanowisk, w których odsłaniają się najstarsze utwory Karpat Zewnętrznych (fliszowych). Po pierwsze, są to odsłonięcia inicjalnych, basenowych osadów późnojurajsko-wczesnokredowych, reprezentujących wczesne stadia węglanowej sedymentacji fliszowej, odbywającej się w obrębie młodego zbiornika protośląskiego (Goleszów - formacja wędryńska, dolina Soły w Żywcu i Jasieniowa Góra oraz Leszna Górna - formacja wapieni cieszyńskich). Po drugie, są to różnej wielkości izolowane bloki skał wapiennych o olistolitowej genezie zwane skałkami andrychowskimi (Targanice, Roczyny i Inwałd), reprezentujące jurajskie utwory o charakterze rafowym i okołorafowym, powstałe w płytkowodnych środowiskach na podmorskim wyniesieniu Baska-Inwałd.
EN
The popularization of educational aspects linked to the geological history of Earth is one of the goals of geotourism, dynamically developing recently. The present paper contains the description of the classic localities exposing the oldest deposits of the Outer Flysch Carpathians. Firstly, these are initial Late Jurassic-Early Cretaceous basinal facies originated during early carbonate flyschoidal stages within the developing proto-Silesian Basin (Goleszów - Vendryne Formation; Soła River valley in Żywiec and Jasieniowa Mt and Leszna Górna - Cieszyn Limestone Formation). Secondly, these are different size limestone blocks, olistoliths in origin, known as Andrychów Klippen (Targanice, Roczyny and Inwałd) represent Jurassic reef and circum-reef environments originated in shallow-water condition on the Baska-Inwałd submarine ridge.
PL
Praca koncentruje się na elementach ważnych dla zrozumienia paleogeografii Zachodnich Karpat zewnętrznych w późnej jurze i wczesnej kredzie w nawiązaniu do litostratygrafii różnych stref facjalnych i opracowania skał macierzystych tworzących się w tym okresie. Opisano szereg elementów paleograficznych: Tetyda alpejska i basen magurski, grzbiet ślaski, basen seweryńsko-mołdawidzki oraz platforma północnoeuropejska. W obrębie tej platformy wyróżniono strefy wyniesione: grzbiet Baska-Inwałd oraz pawłowska platforma węglanowa, a także strefy basenowe: basen bachowicki i basen mikułowski.
EN
The present paper concentrates on the elements important to understanding the paleogeography of the West Carpathians during Late Jurassic and Early Cretaceous times. These elements are linked to the lithostratigraphy of the various facies zones as well as occurrence of hydrocarbon source rocks. Several paleogeographic elements have been described: the Alpine Tethys, Magura Basin, Silesian Ridge, Severin-Moldavidic Basin and North European Platform. The uplifted and basinal zones were distinguished within the platform. The Baska-Inwałd Ridge and Pavlov Carbonate Platform belong to the uplifted elements, while Bachowice and Mikulov basins represent the basinal zones.
PL
Dolnokredowe warstwy węglowieckie stanowią kolektor ropy naftowej i gazu w złożu Węglówka, które stanowi jedno z najwcześniej odkrytych złóż ropy w Karpatach fliszowych. W obrębie dwóch fałdów odsłaniających się w półoknie tektonicznym Węglówki zarejestrowano szereg profili warstw węglowieckich, w których zgodnie z metodyką analizy facjalnej opisano następujące litofacje: piaskowce zlepieńcowate (SC), piaskowce (S), piaskowce z mułowcami (SM), mułowce z piaskowcami (MS) oraz mułowce (M). Dla piaskowców wchodzących w skład litofacji SC, S i SM oznaczono gęstość pozorną i nasiąkliwość. Badania petrograficzne obejmowały obserwacje w mikroskopie optycznym i skaningowym oraz w katodoluminescencji, a także badania porozymetryczne i oznaczenia współczynnika przepuszczalności. Wyniki badań wskazują na dwa czynniki odpowiedzialne za korzystne właściwości zbiornikowe piaskowców węglowieckich. Pierwszy stanowi wczesna i ograniczona cementacja krzemionkowa, mająca istotne znaczenie dla opóźnienia postępu kompakcji i zachowania porowatości osadu w początkowej fazie diagenezy. Drugi czynnik to koncentracja cementu węglanowego w obrębie konkrecji. Bioklasty krzemionkowe oraz najdrobniejsze frakcje ziaren kwarcu stanowiły źródło mikrokrystalicznego cementu kwarcowego oraz cementu chalcedonowego. Lokalnie wysoka zawartość biogenicznej krzemionki była przyczyną obfitej cementacji chalcedonowej. Cementacja węglanowa przyczyniła się do znacznej redukcji tej przestrzeni porowej, jaka zachowała się po wcześniejszej kompakcji osadu i cementacji krzemionkowej. Cement węglanowy, jak również okruchy węglanowe rejestrowano tylko w obrębie konkrecji, podczas gdy w ich otoczeniu stwierdzono brak detrytycznego materiału węglanowego i cementu węglanowego. Zatoki korozyjne w ziarnach kwarcu i skaleni notowane w otoczeniu konkrecji stanowią ślady po pierwotnych węglanach. Proces powstawania konkrecji węglanowych w piaskowcach węglowieckich można uznać jako wczesnodiagenetyczny, przemawia za tym wysoka zawartość cementu węglanowego oraz luźne upakowanie ziaren szkieletowych w obrębie konkrecji. Stwierdzono, że główną rolę w kształtowaniu cech zbiornikowych odgrywa skład mineralny materiału okruchowego, który decyduje o kierunku przemian diagenetycznych i wykształceniu określonego zespołu spoiw, podczas gdy litofacje są mniej istotne dla ich właściwości kolektorskich.
EN
The Early Cretaceous Węglówka Beds is the reservoir of the Węglówka Oil Field, one of the earliest discovered in the Outer Carpathians (exploitated since 1888). This region is the cradle of world oil exploration and petroleum industry. The Węglówka Beds form two anticlines within the half-window of the Sub-Silesian Unit. A sedimentological analysis of several sections revealed the following lithofacies of the subaqueous gravity flow: conglomeratic sandstones (SC), sandstones (S), sandstone-mudstone couplets (SM), mudstone-sandstone couplets (MS) and mudstones (M). Apparent density and water absorptivity were determined for 47 sandstone samples collected from the facies SC, S, SM. The 15 most differentiated samples were selected for further petrographic and diagenetic studies with optical and scanning electron microscopes, X-ray diffraction and cathodoluminescence. Furthermore, mercury injection curves and permeability coefficients were determined. The results of analyses indicate that two factors are responsible for the good/positive reservoir properties of the Węglówka Sandstone. The first factor is the early and limited siliceous cementation. Siliceous sponge spicules and very fine quartz grains were the source of sparse chalcedonie cement and microcrystalline quartz, which formed rims around the grains while pores remained free. Compaction was inhibited and initial porosity was preserved to a large extent. Stronger chalcedonie cementation and the reduction of porosity occurred only locally as the result of the high content of biogenic silica. The other factor is the carbonate cement, which occurs only in spots (concretions). Carbonate cementation brought about a large reduction of the pore space within the concretions, which survived compaction and siliceous cementation. Both carbonate cement and carbonate detrital material were observed only within concretions. Corrosion of quartz and feldspars was the only trace of primary carbonates in their close vicinity. In turn, the abundance of the carbonate cement and a loose grain framework in the carbonate concretions was the evidence of the early origin of concretions. The study has revealed that the mineral composition of the detrital components controlled the diagenesis and formation of specific assemblages of cements and thus played the main role in modelling the reservoir properties of the Węglówka Sandstone. Those properties were controlled by the sedimentary conditions (facies) to a far lesser extent.
EN
The macrofaunal content of an exceptionally fossiliferous Late Albian core section is described from Zippelsforde in the Brandenburg district in eastern Germany. The main faunal horizon includes among others Euhoplites vulgaris, Mortoniceras (Deiradoceras) albense, Neohibolites minimus, Inoceramus cf. anglicus and Actinoceramus sulcatus. This assemblage indicates a Hysteroceras varicosum Zone, Hysteroceras orbignyi Subzone age. That interval is known from the Anglo-Paris as well as from the Lower Saxony Basin in western Germany, but not was previously recorded from the North East German Basin. Therefore, the record fills a palaeogeographical gap between the Albian in the Carpathians and that of Central Europe. The superjacent interval contains Aucellina gryphaeoides, dating it as latest Albian (Mortoniceras (M.) inflatum Zone, late C. auritus Subzone or younger), and thus indicating a significant condensation within the Late Albian.
EN
Dinocyst assemblages (150 taxa) were recognised in the Lower Cretaceous deposits of the Grajcarek Unit, Pieniny Klippen Belt (West Carpathians). The following dinocyst based ages were established: a Hauterivian-Barremian boundary level age in the Sztolnia section (Pieniny Limestone Formation); a Late Barremian age of the top part of the Pieniny Limestone Formation (Rzeźnia section); a Late Barremian -Early Aptian age of the Kapuśnica Formation, Brodno Member (Rzeźnia section); latest Barremian-Early Aptian and Late Albian-Cenomanian ages of the Wronine Forma- tion (Rzeźnia section); Late Albian-Cenomanian (Hulina section) and the latest Albian-Cenomanian (Sztolnia section) ages of the Hulina Formation. Palynofacies assemblages were described and differentiated into five types, PT1 to PT5, reflecting various palaeoenvironments. Presence of anoxic events, as based on amorphous-organic-matter-dominated palynofacies, was recognized.
EN
Early Cretaceous calpionellid samples were collected at the ammonoid-bearing Hochkogellocality in the southern most part of the Reichraming Nappe (Ebenforst Syncline, Northern Calcareous Alps). The microfossil fauna sampled from limestone parts of the Rossfeld Formation indicates an early Valanginian age. The standard Calpionellites Zone (with darderi and major subzones) coincides with the early Valanginian ammonoid zones of Busnardoites campylotoxus and Tirnovella pertransiens. The deposition of the limestones in this area occurred in an unstable environment disturbed by gravitational transport which accounts for the different sedimen tary components and accompanying fossils in the accumulated layers, transported from a source area situated to the south.
12
Content available remote First nearly complete skeleton of the Cretaceous duvaliid belemnite Conobelus
EN
The first Cretaceous belemnite preserved with the rostrum, slightly compressed phragmocone and part of the proostracum is described from the Early Cretaceous (Late Valanginian) Rossfeld Formation (Eibeck, Reichraming Nappe of the Northern Calcareous Alps). The rostrum has dorsal groove (alveolar furrow) typical of duvaliids, and its conical shape (round in transverse section outline), and the rounded apex allow its attribution to Conobelus Stolley, 1919. The new species C. pseudoheres sp. nov. is proposed based on the unique features of the specimen, i.e. persistently parallel lateral sides throughout the rostrum and the conical, blunt outline at the apex. The ration between rostrum and phragmocone is 0.78; the distances between the calcitic septa of the anterior end of the phragmocone range from 3 to 5 mm. The proostracum is 0.02 mm thick. The apical angle is 32° and the alveolar angle (posterior end of the phragmocone) is 24°.The alveolus is 40 mm long, yielding a ratio between rostrum and alveolus of 1.86. The depositional history with its fast sedimentation along with absent/limited post-mortem transportation led to extraordinarily good preservation of the examined specimen.
EN
Sanmartinoceras aff. walshense (ETHERIDGE, 1892), a single large representative of the Aconeceratinae SPATH, 1923 from California is believed to be a macroconch. It shows close relations to Sanmartinoceras africanum KENNEDY & KLINGER, 1979 and Sanmartinoceras walshense, however the described combination of features is unique. Until the variability of this ammonite is established we assign this specimen to Sanmartinoceras aff. walshense. It is probably Late Aptian in age and represents the first evidence of the Aconeceratinae in North America
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