Mid-Cretaceous spicule-rich turbidites in the Silesian Nappe of the Polish Outer Carpathians : radiolarian and foraminiferal biostratigraphy

Spicule-rich turbidites are widespread inmid-Cretaceous deep-water flysch of the Subsilesian and Silesian units in the Polish Outer Carpathians. The spicule-rich material with an admixture of numerous radiolarian and foraminiferal particles was supplied, together with siliciclastic material, from shallow environments, mostly from the northern margin of the Carpathian Basin. We present new data on theage of these deposits in the Silesian Nappe, where they are distinguished as the Mikuszowice Cherts. This unit is composed of medium-and thick-bedded siliciclastic to calcareous turbidites including bluish cherts in their middle and upper parts and of thin non-calcareoushemipelagic shales. We have studied radiolaria and foraminifera from hemipelagic sediments and spicule-rich turbidites, from two con-tinuous sections in the Barnasiówka Range (Beskid Wyspowy Mts.) that included the Mikuszowice Cherts (31 m thick) and their transition into the surrounding units. The age of the Mikuszowice Cherts was determined taking into account the following radiolarian datumevents: (1) the occurrence of Praeconocaryomma lipmanaein the entire unit, (2) the FO (first occurrence) of Hemicryptocapsa tuberosain the upper part of the unit, (3) the FO of Amphipyndax stockiclose to the upper boundary of the unit, (4) the FO of Hemicryptocapsa prepolyhedra in the lowermost part of the overlying Barnasiówka Radiolarian Shale Formation. These datum events appear successivelyin the Western Tethys successions within the Rotalipora cushmani planktonic foraminiferal Zone, which corresponds to the middle andupper Cenomanian (except for its uppermost part). The foraminiferal assemblages, in which such taxa as Rotalipora cf.cushmani, R. cf. greenhornensis, whiteinellids and Uvigerinammina praejankoi successively appear, confirm the mid-late Cenomanian age of thespicule-rich turbidites in the Silesian Nappe

Evidence of bacteriogenic iron and manganese oxyhydroxides in Albian-Cenomanian marine sediments of the Carpathian realm (Poland)

The Albian and Cenomanian marine sediments of the Silesian and Tatric basins in the Carpathian realm of the Western Tethys contain ferric and ferromanganese oxyhydroxides, visible macroscopically as brown stainings. They coat calcareous bioclasts and mineral clasts, fill pore spaces, or locally form continuous, parallel microlayers, tens of micrometers thick. Light-microscope (LM) and scanning-electron-microscope (SEM) obser- vations show that the coatings contain elongated capsules, approximately 3-5 \mum across and enriched in iron and manganese, which may be remnants of the original sheaths of iron-related bacteria (IRB). Moreover, the ferric and ferromanganese staining observed under LM is similar to bacterial structures, resembling the sheaths, filaments and rods formed by present-day bacteria of the Sphaerotilus-Leptothrix group. All of the possible bacteria-like structures are well preserved owing to processes of early diagenetic cementation. If the observed structures are fossil IRB, these organisms could have played an important role in iron and manganese accumulation on the sea floor during Albian-Cenomanian time. The most plausible source of metals for bacterial concentration in the Silesian Basin might have been submarine low-temperature hydrothermal vents, as previously was hypothesized for Cenomanian-Turonian deposits on the basis of geochemical indices

Exotic orthogneiss pebbles from Paleocene flysch of the Dukla Nappe (Outer Eastern Carpathians, Poland)

Crystalline exotic pebbles have been found in the deep-water flysch of the Cisna Beds, in the Dukla Nappe,Polish part of the Outer Western Carpathians. Most of them occur in a layer, which extends over a distance of at least 3 km within the SE limb of the Chryszczata-Wołosañ-Mała Rawka anticline. The dimensions of the pebbles vary be-tween 2 and 18 cm (middle axis). The exotic pebbles consist of three types of granite derived orthogneisses: 1 - medium-grained, medium-banded orthogneiss with alkali feldspar porphyroblasts showing structural features of foliatedgranitic-gneiss, 2 - medium-banded, medium-layered orthogneiss containing small microcline porphyroblasts and showing structural features of foliated granitic-gneiss, and 3 - strongly cataclastic granitic-gneiss with chess-board albiteporphyroblasts showing properties of partly mylonitized granite. The chemical composition of the orthogneisses indi-cates that the protolith was represented by peraluminous, poorly-evolved, S-type granites exhibiting features of orogen-related crustal granites. The discrimination shows that the protolith of the studied rocks evolved in active continentalmargin or continental collision environments. The biostratigraphical data on deep-water agglutinated Foraminifera suggest the position of the exotic-bearing layer in the lowermost part of the Rzehakina fissistomata Zone corresponding tothe lowermost Paleocene. Petrographic affinities between orthogneissic pebbles and mineral/rock fragments grains ofthe Cisna-type sandstones show that they have the same provenance. These deposits were transported from the NEextension of the Marmarosh massif, which had the character of a continental bearing source cordillera, formed mainly byorthogneissic and granitic rocks

Successive stages of calcitization and silicification of Cenomanian spicule-bearing turbidites based on microfacies analysis, Polish Outer Carpathians

Mid-Cretaceous turbidites with large proportions of sponge spicules are widely distributed in the Silesian Nappe of the Outer Carpathians, giving rise to diversified types of sediments, from spiculites to spicule-bearing siliciclastics and calcarenites. Part of this succession, Middle–Late Cenomanian in age, was transformed into cherts. A microfacies study showed that these turbidite sediments underwent several stages of calcitization and silicification, which took place during Mid-Cretaceous times in different sedimentary environments, i.e., on a northern shelf bordering the Silesian Basin and on a deep sea floor. The first diagenetic changes were related to changes to the biotic components of the turbidite layers, dominated by siliceous sponge spicules. This process, which took place in the spiculitic carbonate mud on the shelves, was related to the calcitization of sponge spicules. Calcareous clasts and calcified skeletal elements also were corroded by bacteria. After transportation down the slope, the biogenic and siliciclastic particles were deposited below the carbonate compensation depth. Taphonomic processes on the basin floor and alternating phases of carbonate and silica cementations, recrystallization and dissolution occurred in these sediments and were related to the diversification in composition of successive turbidite layers. Silicification was related to the formation of quartz precipitates as fibrous chalcedony or microcrystalline quartz, which were derived from the earlier dissolution of amorphous silica, originating mostly from siliceous sponge spicules and radiolarian skeletons. However, a source of silica from hydrothermal vents was also possible. The initial silica precipitation could have taken place in a slightly acidic environment, where calcite was simultaneously dissolved. A number of silicification stages, visible as different forms of silica precipitate inside moulds after bioclasts, occur in the particular turbidite layers. They were related to changes in various elements of the pore-water profile after descending turbidity-current flows. A very low sedimentation rate during the Middle–Late Cenomanian in the Silesian Basin may have favoured the sequence of initial calcitization and silicification stages of the turbidite sediments

Stromboli – the best place to actively learn and understand the behavior of an active volcano and its processes // Stromboli – najlepsze miejsce do poznania aktywnego wulkanu i zrozumienia procesów wulkanicznych

Basaltic volcanism, a dominant mode of volcanic activity on Earth, occurs as explosive eruptions, resulting from the exsolution of magmatic gases and is exhibited by Strombolian and Hawaiian types. Strombolian activity takes its name from frequent, small-scale explosions of the Stromboli Volcano, which was formed within the Aeolian Islands, north of Sicily. This paperpresents the volcanic structure and features of its activity, based on the results of numerous studies carried out during the last 15 years. In the intention of the authors, this educational presentation would be an incentive to make a decision to travel to Stromboli and see its present-day activity and its effects from just a few hundred meters. To have a safe experience and to avoid accidents and injuries, the tourists need to have sufficient up-to-date information, before they embark on their adventure.//Wulkanizm bazaltowy (dominujący typ aktywności wulkanicznej na Ziemi), który jest związany z ekshalacją gazów pomagmowych, ma charakter eksplozywnych erupcji określanych mianem typu hawajskiego i strombolijskiego. Aktywność strombolijską charakteryzują częste, niewielkiej objętości wybuchy, które występują m.in. na czynnym wulkanie Stromboli, znajdującym się w łuku Wysp Liparyjskich (Eolskich), na północ od Sycylii. W artykule przedstawiono budowę wulkanu, jego działalność i przyczyny tej działalności na podstawie wyników licznych badań, przeprowadzonych w ciągu ostatnich 15 lat. W intencji autorów przedstawione w sposób możliwie prosty informacje, zdjęcia i ryciny tego wulkanu mają być materiałem edukacyjnym i jednocześnie zachętą do podjęcia decyzji o podróży, żeby z odległości kilkuset metrów móc samemu zobaczyć erupcje wulkaniczne. Aby poznawanie wulkanu było bezpieczne, turyści powinni zapoznać się z aktualnymi informacjami o warunkach panujących na ścieżkach turystycznych

Early Carboniferous trilobite remains from limestones of the Dębnik Anticline, southern Poland

The presence of proetid trilobites remnants is reported for the first time from the early Carboniferous limestones of the Dębnik Anticline outcropped in the Racławka valley, the eastern part of the Upper Silesian Block (southern part of the Cracow Upland). Disintegrated exoskeletons of trilobites have been found in thin sections of fine-grained, peloidal wackstones and packstones. These rocks contain also foraminifers which indicate the Early Tournaisian age of this founding

Grafika cyfrowa 2019 : opus 1634-1636

Trzy grafiki cyfrowe autorstwa Krzysztofa Marka Bąka

Ludowość a ekslibris : wątki ludowe w księgoznaku i grafice kommemoratywnej

For centuries, the form of bookplates was shaped by European epochs of art. Folk aesthetics was no reflection on their iconography. The situation changed in the 20th century, especially in the period after the war, when in Poland a thriving and active circle of artists performing folk motifs was established. A similar situation occurred in Central and Eastern Europe. Modern transformations almost entirely eliminated rural topics from bookplates. However, the observation of other manifestations of culture (including popular culture) suggests that folklore has great potential to become again a source of inspiration for artists creating bookplates, especially of the youngest generation

Jesteśmy Śląskiem

Tryptyk śląski” jest wyrazem naszego postrzegania, współodczuwania, tworzenia Śląska, rozumianego zarówno jako kraina geograficzno-historyczna, gdzie przyszło nam żyć i pracować, pojmowanego jako stan mentalny – indywidualne dziedzictwo wspomnień i doświadczeń – oraz widzianego jako nasza przyszłość, której jesteśmy współautorami, wnosząc swój wkład w jego rozwój (Fragment tekstu)