A multi-phase succession of karst sinkhole deposits in the tectonic zone of the Owad & oacute;w-Brzezinki limestone quarry at the north-western margin of the Holy Cross Mts. was studied in detail, using petrographic, palynological and other palaeontological methods. Upper Jurassic limestones are covered by a residual reddish brown clay layer of terra rossa type and a yellow-brown, loose calcareous deposit of a silt fraction. The yellow-brown calcareous silt consists of rhombohedral calcite grains, which may have been formed by the disaggregation of speleothems. The colouration of both deposits and clay mineral admixtures point to intensive weathering under a subtropical climate. The successive deposits of the sinkholes include coaly clay and a layer of whitish, microcrystalline, siliceous sinter. The coaly clay yielded a rich Middle Miocene palynofloral assemblage, indicative of a warm temperate and humid climate, as well as freshwater algae, which inhabited surface-water pools. The origin of the siliceous sinter probably is related to the activity of a hot spring. The youngest, massive infillings of the sinkholes consist of grey silty clays, which yielded marine bivalves, gastropods and Dichotomites ammonites, diagnostic for the Upper Valanginian as well as white yellow quartz sands of Upper Hauterivian? - Middle Albian age. The massive siliciclastic deposits probably slumped into the sinkholes during their final collapse. The sinkhole infillings document the development and timing of karst processes, Middle Miocene climatic conditions and the original succession of Lower Cretaceous-Neogene strata of the study area, which were removed from the surface by erosion.
The diagenesis of biosilica remains poorly known, but is increasingly important for reconstructing past oceanic silica levels using silicon isotopes. Here, we present SEM and XRD analyses of sponge spicules from the Late Jurassic, Late Cretaceous, and Eocene, compared with modern samples, to reveal their modifications with time. Modern spicules are composed of opal-A, distinct from sinter-derived opal-A. Many Eocene spicules also preserve opal-A, but show signs of early transformation. Most Eocene and all Cretaceous spicules consist of opal-CT, while quartz occurs in some Cretaceous and all Jurassic samples. Eocene opal-A spicules are macroscopically glassy, whereas opal-CT spicules exhibit a milky and/or opaque appearance, due to the presence of silica micro-spheres. Cretaceous spicules range from milky to opaque, and Jurassic spicules are typically opaque, containing microspheres, silica nanogranules, and microquartz. The structural and mineralogical evolution is reflected in decreasing Full Width at Half Maximum (FWHM) values of diffractograms with increasing age. Some Cretaceous and Jurassic spicules contain quartz blocks, formed by the fusion of silica nanogranules, while euhedral quartz occurs in both Cretaceous and Jurassic samples. Although diagenetic stages can vary within a single spicule, all retain at least some elements of their original structure and morphology. The observed mineralogical transitions reflect dominant solid-state maturation through dehydration and sintering and/or Ostwald ripening, rather than dissolution, mould formation, and reprecipitation from external fluids. Our findings indicate that sponge spicules preserved through solid-state transformation are preferred targets for silicon isotope studies. However, the assumption that such spicules retain their original isotopic signal must be further verified through integrated structural and isotopic investigations.
Several dozen samples of silicified wood were discovered during a renewed geological mapping survey in the Sudetes Mountains (NE Bohemian Massif, SW Poland). The material originates from the Metuje River valley, near Kudowa-Zdr & oacute;j (Kudowa-S & lstrok;one locality), where woody debris is embedded in the unconsolidated gravelly Quaternary alluvial deposits that form a river terrace. The silicified wood occurs as clasts in a gravelly lithofacies. To determine the taxonomic affinity, taphonomic history, and provenance of the material, the specimens were analysed macroscopically and using petrographic microscopy, cathodoluminescence imaging and scanning electron microscopy. The wood is assigned to Cordaixylon, a cordaitalean genus, characteristic of Late Palaeozoic forest ecosystems. Despite its occurrence as barkless and branchless fragments in unconsolidated, Quaternary sed-iments, the secondary xylem anatomy is exceptionally well-preserved. This combination of anatomical fidelity and physical abrasion indicates that the material is allochthonous and records a multi-stage depositional history. Sedi-mentological and palaeobotanical evidence demonstrates that the wood was derived from Carboniferous strata and had experienced at least two phases of fluvial redeposition: first within Carboniferous arkosic channel deposits, and later within Late Quaternary river-terrace sediments. Palaeoflow indicators and clast petrography from the Kudowa-S & lstrok;one exposure show persistent southward transport of gravel and woody debris, with the principal source area located to the north. These data support a provenance from the Late Carboniferous Jivka Member of the Odolov Formation, in the eastern (Czech) part of the Intra-Sudetic Basin, where cordaitalean wood is abundant and exposed in Carboniferous strata, incised by the Metuje and D & rcaron;evi & ccaron; rivers.
Hornsund is undergoing rapid environmental transformations, driven by ongoing atlantification of the Arctic. This study examines how foraminiferal assemblages have responded to these changes over the past two decades, providing an exceptional opportunity to link modern ecosystem dynamics with processes recorded in the sedimentary archive. The primary objective of this study aims is to establish diagnostic faunal and isotopic features of atlantification that can be applied in the interpretation of palaeoceanographic records. Results reveal clear indicators of atlantification, including the increasing dominance of boreoarctic and Atlantic Water (AW)-affiliated taxa (Adercotryma glomeratum Brady, Astrononion hamadaense Asano, Nonionellina labradorica Dawson, Recurvoides turbinatus Brady), prevalence of opportunistic species (Cassidulina reniformis N & oslash;rvang, Cribroelphidium clavatum Cushman), rising species richness and a greater abundance of agglutinated taxa, particularly in the inner fjord. Spatial distribution patterns reflect progressive AW penetration towards the fjord head, with outer and central fjord stations exhibiting high diversity and evenness, and inner glacial-proximal areas showing increased agglutinated foraminifera dominance. Stable-isotope analyses of selected foraminiferal tests demonstrate increasing delta O-18, consistent with higher salinity, and decreasing delta C-13, indicative of enhanced primary productivity and terrestrial organic matter input. These changes, occurring within just 22 years, reveal the high sensitivity of benthic foraminifera to environmental change in the Arctic and confirm their value as proxies for reconstructing both contemporary and palaeoceanographic changes in high time resolution.
Quantitative description of the rock pore space properties provides important data for considerations, related to the quantitative description of mass transport or estimation of the aquifer's resources. Carbonate rocks are characterized by a particularly complex groundwater flow system. The hydraulic network in these rocks consists of three types of voids: pore space (matrix), fractures and caverns. The authors present the results of research on selected hydrogeological parameters of the Jurassic rock samples, taken from drill cores in the Olkusz region and Krak & oacute;w (southern Poland). The values of porosity, hydraulic conductivity, specific yield and relative drainability were determined; 159 samples from the Olkusz region and 90 samples from the Krak & oacute;w region were tested. The porosity of the tested samples varied from 0.64% to 21.9% for the Olkusz region and 0.62%-9.6% for Krak & oacute;w. Hydraulic conductivity ranged from 2.52x10(-12) m/s to 1.53x10(-9) m/s for the Olkusz region and from 5.40x10(-12) m/s to 9.06x10(-7) m/s for Krak & oacute;w and the specific yield from 0 to 0.0123 for the Olkusz region and from 0.00051 to 0.00737 for Krak & oacute;w. There were no statistically significant relationships between the values of individual parameters for samples, tested perpendicular and parallel to the direction of drilling the test borehole in the case of samples from the Olkusz area. In the case of samples from Krak & oacute;w, there was a weak, but statistically significant correlation between specific yield vs porosity, and the correlation between specific yield vs hydraulic conductivity
The complex of freshwater carbonates at & Ccaron;eren & aacute; Hill in northern Slovakia was investigated. The facies recognised are mainly represented by a laminated crust, micritic limestone and phytoclastic boundstone and subordinately by moss boundstone and carbonate-siliciclastic mud. The alluvial sediments present at the base of the complex indicate that it was deposited within a flat stream valley at the foot of the Low Tatra Mts. The growth of the carbonates was controlled by the supply of deep-circulation water, containing geogenic CO2, and its outflow to the marshy floodplain. This area was occasionally invaded by surface stream water, resulting in modification of the sedimentary facies, accompanied by a slight differentiation of the geochemical data (delta 13C values and CaCO3 content). The U-series and palaeomagnetic data collectively show that the growth of the spring-related carbonate complex commenced between ca. 300 ka and persisted until 200 ka. Deposition during the warm interglacial phases of the Pleistocene is assumed; this is supported by the presence of a malacofauna assemblage, and a high contribution of calcified floral remains in a part of the studied sediments. Post-sedimentary modifications, mainly mass-wasting processes, resulting from the incision of adjacent valleys, shaped the area of & Ccaron;eren & aacute; Hill after it was cut off from a deep-water supply.
On the basis of palynologic and palynofacies data from the Bia & lstrok;y Kamie & nacute; Formation in the Intra-Sudetic Basin (ISB), the composition of parent plant communities and the depositional environment during sedimentation of this unit were reconstructed. The results were then compared with earlier published palynological data from the stratigraphically older and younger lithostratigraphical units, the Wa & lstrok;brzych and & Zcaron;acl & eacute;& rcaron; formations, allowing a general interpretation of floristic and environmental changes throughout the Serpukhovian to Moscovian interval. The floras in the Serpukhovian resemble the composition in the Moscovian. In both, their main feature is low lycopsid abundance, indicating relatively dry palaeoclimatic conditions. In contrast, the Bashkirian records a gradual increase in lycopsids and sphenopsids, peaking in the late Bashkirian during the maximum humid phase. This was followed in the Moscovian by a marked decline in lycopsids and a shift toward fern dominance, reflecting a transition to a drier climate associated with the First Dry Interval, proposed by Phillips and Peppers (1984). At the same time, the miospore record shows no evidence of abrupt floristic changes, contradicting the concept of a "floristic leap" at the Namurian A/B boundary.
Kimmeridgian carbonate facies from the southern margin of the & Lstrok;& oacute;d & zacute; Depression are rich in crinoid remains, dominated by stalked forms. Free-living comatulids (adult stemless crinoids), however, have remained largely undocumented in this area, with only a single specimen reported to date. Our newly collected material includes several dozen comatulid remains, primarily represented by centrodorsals. These specimens are assigned to Solanocrinites sp., Comatulina sp., Palaeocomaster cf. karsensis Radwa & nacute;ska, and Semiometra petitclerci (Caillet). In addition, stalked comatulids belonging to the family Thiolliericrinidae are documented, including Thiolliericrinus flexuosus Goldfuss and Solonaerium cf. sigillatum (Quenstedt), the latter two species being reported from Poland for the first time. This study also provides a review of the Kimmeridgian stalked crinoids (Isocrinida, Millericrinida, Cyrtocrinida) and Upper Jurassic comatulids previously recorded from Poland. The new occurrences originate from lower Kimmeridgian sponge-bivalve-oncoid biostromal limestones and marly limestones, as well as from thin-bedded marls and marly limestones. Within the epicontinental platform of the northern Tethyan shelf, these facies represent mid-to outer-platform transgressive successions. Their development was particularly pronounced during the late Oxfordian to early Kimmeridgian (up to the Hypselocyclum Zone) limestone-dominated platform stage and continued into the marl-dominated platform stage of the early Kimmeridgian (Hypselocyclum-Divisum zones).
The study of the lower Berriasian (Lower Cretaceous) of the Sierra del Pozo (Internal Prebetic, Betic Cordillera) has made possible the discovery of three dinosaur tracks that correspond to the digitigrade footprints (28.7 to 26.1 cm long and 19.9 to 21.4 cm wide) of mesaxonic tridactyls. The tracks are located at the top of two shallowing-upwards sequences with desiccation-related mud cracks that correspond to supratidal facies. The trackmakers were medium-sized theropods, on the basis of the prints record, the claws, the elongated digits and the low interdigital angles. This is the only record at the South-Iberian Palaeomargin of theropod tracks, which are relatively scarce, compared to the Lower Cretaceous of other Iberian Palaeomargins.
Major geological and ecological transformations, linked to the progressive opening of the ocean basins, extensional tectonics, and changes in pelagic sedimentation occurred across the Tethys during the Bajocian-Tithonian interval. This study reconstructs supra-regional palaeoenvironmental changes, based on pelagic deposits from the Niedzica-Podmajerz section of the Pieniny Klippen Belt, representing the Alpine Tethyan domain. An integrated dataset, including carbon isotope stratigraphy, biostratigraphy, microfacies analysis, and CaCO3 content, provides insights into sedimentary evolution along a submarine slope. The succession reflects a long-term deepening trend, beginning with neritic crinoid-dominated deposition, followed by the accumulation of deeper-shelf sediments, rich in Bositra sp., juvenile ammonites, and gastropods, and continuing into basinal deposits, characterized by Globuligerina, radiolarian, and Saccocoma-filamentous and Globochaete-Saccocoma assemblages. This facies evolution parallels global phenomena, such as the transgression at the Middle-Late Jurassic transition, a carbonate production crisis, ocean acidification, climate changes and circulation changes, linked to the opening of the Atlantic-Tethys Seaway. Specific intervals of the studied section were assigned to the Oxfordian (Fibrata Zone), the Kimmeridgian (Parvula Acme, Moluccana, and Borzai zones), and the Lower Tithonian (Pulla Acme, Malmica, and Cieszynica zones), on the basis of calcareous dinoflagellate cyst analysis. These intervals correspond to key delta C-13 events: the Late Callovian-earliest Oxfordian and Kimmeridgian positive events and a minor negative shift near the Kimmeridgian-Tithonian boundary.
Palynological analysis of samples taken from the lignite, exposed in the Ch & lstrok;apowo Cliff on the southern Baltic coast, allowed the reconstruction of the vegetation and palaeoclimate that predominated during the accumulation of the peat, from which the lignite was formed. In addition to pollen grains and spores, particular attention was given to non-pollen palynomorphs, such as algal, fungal and invertebrate micro-remains (Cladocera) that enabled a more accurate reconstruction of the palaeoenvironment. The lignite belongs to the 2nd Lusatian seam, which is an important correlation level in Central Europe, dated to the latest Early Miocene to the early Middle Miocene. The textural and structural features of the lignite seam indicate that the depositional environment of the peat is loosely combined with the overbank zone of an anastomosing or meandering river system. The results of the palynological study show the presence of wetland vegetation, including shrub bogs (most similar in their composition to modern pocosins, growing between river channels) and riparian forests, growing on periodically flooded areas and mesophilous vegetation, occurring in the vicinity. The composition of the palynoflora, including the thermophilic taxa, such as Sapotaceae and Meliaceae, indicates that the climate was warm, close to subtropical, with a mean annual temperature range of 15.7-17.8 degrees C.
Plant fossils were studied in samples from the Upper Jurassic (lowermost Kimmeridgian) locality at the village of W & oacute;lka Baltowska in the Holy Cross Mountains (G & oacute;ry $wi & ccedil;tokrzyskie), collected in the 20th century by Jerzy Liszkowski. Eight macrofossil taxa were recognized: an indeterminate sphenophyte, a fern cf. Gleichenites cycadina, seed fern Ptilozamites cycadea, conifers, Brachyphyllum mamillare with female cone scales and male cones, containing Araucariacites and Callialasporites pollen grains in situ in pollen sacs, Brachyphyllum crucis and probably its male cone, Pagiophyllum araucarinum, an unassigned conifer male cone, and the gymnosperms incertae sedis Pseudotorellia solida sp. nov. and Taeniatus elongatus. The latter was for the first time found with a preserved cuticle, enabling emendation of the generic and specific diagnosis. Additional data, from the palynological analysis of six samples that yielded organic-walled dinoflagellate cysts (dinocysts) and sporomorphs, as well as rich phytoclast assemblages, including large cuticle remains, complement the vegetation picture and allow reconstruction of the palaeoenvironmental conditions. Palynological analysis confirms that the plant-bearing limestones were deposited in a nearshore, presumably shallow-marine sedimentary setting. Interpretation of the macroremains indicates that nearby land (probably an island) was covered by vegetation, typical for a nearshore marine-influenced zone, while some sporomorphs were probably transported (from inland or the vicinity).
Zittelia is an extinct genus of the family Colombellinidae, which originally was described from the Upper Jurassic-?Lower Cretaceous (Tithonian-?Valanginian) of Sicily, Italy, and subsequently reported from sev-eral localities across Europe. Its shell is oval, with a thickened, siphonostomatous peristome, a narrow, slit-like ap-erture displaying distinct abapical sinuosity, and a denticulate outer lip that is bent outward. In contrast to members of the Cypraeidae, the shells of which are convolute, the spire of Zittelia remains elevated. A thorough examination of the type material has enabled a comprehensive revision of the taxonomic composition of the genus and clarifica-tion of its diagnostic characteristics. Species of Zittelia share morphological affinities with Colombellina, the type genus of the Colombellinidae, and are closely related to early representatives of the cypraeids. This is reflected in changes in the shell morphology of Zittelia during the Late Jurassic, including a progressive enlargement of the last whorl, elongation of the aperture, and a substantial expansion of the columellar lip. The species most closely re-sembling early cypraeids is the type species, Zittelia cipraeaeformis Gemmellaro, 1869, which possesses a broadly expanded columellar lip and a low spire. The occurrence of Zittelia is restricted to peri-Tethyan carbonate facies. Its co-occurrence with the earliest cypraeids in the uppermost Jurassic of Sicily indicates that the Late Jurassic reefs and associated lagoons of the Tethys may have served as centres of diversification for the Colombellinidae and as potential areas of emergence for the Cypraeoidea.
Within the Eocene turbidites of the Ra & ccaron;a Zone of the Magura Nappe, a middle Eocene olistostrome complex approximately 200 m thick is present, containing redeposited middle Eocene, lower Eocene, and Paleocene deep-sea basinal deposits, as well as blocks of shallow-marine middle Eocene limestones and igneous rocks. It forms part of a large olistostrome horizon. The olistostrome originated through a series of individual gravitational slope failures. The displaced deposits occur in packets, separated by regular turbiditic deposits. In three sections, the following depositional units were identified: (1) a package of sedimentary m & eacute;lange with blocks of metagabbro, serpentinite, and limestone; (2) a package of deformed turbidites; and (3) a package with olistoplaques of shales and marls, containing blocks of granitoid and limestone. The source area was located in the northern part of the basin and included a carbonate platform and basin slope. The material underwent relatively brief gravitational transport during the Bartonian. The age of the olistostrome was established on the basis of foraminifera: the Haplophragmoides acme and Praesphaerammina subgaleata (Va & scaron;& iacute;& ccaron;ek) acme and Eocene marker taxa, e.g., Reticulophragmium amplectens (Grzybowski), Ammodiscus latus Grzybowski forma ovoidalis, as well as Eocene species of Subbotina andAcarinina. This olistostrome is one of several large ones that developed in the Carpathian part of the Tethys at that time.
The Pieniny Klippen Belt forms a narrow suture zone between the Central and Outer (Flysch) Carpathians and is composed of deposits, laid down in the Alpine Tethys. The lithostratigraphy and tectonic structure of the central part of Pieniny Klippen Belt west of the Bialka River, in the area between Krempachy and Stare Bystre, were analysed. The Pieniny Klippen Belt is made up of a mixture of components of different ages and lithologies, referred to as a m & eacute;lange, which was formed as a result of complex tectonic and sedimentary processes. In the lithological inventory, it contains rocks from the Jurassic up to the Miocene age, which originated in the syn-rift and synorogenic stages of Alpine Tethys evolution. Sedimentation in the Alpine Tethys took place in conditions from shallow-to deep-water, related to the development of the uplifted structure of the Czorsztyn Ridge in its central part. The carbonates and carbonate-siliceous rocks of the syn-rift stage are fragmented and occur in the form of blocks of different sizes within the flysch deposits of the synorogenic stage of development. The flysch depos-its of the synorogenic stage are bounded by the results of activity of the accretionary prism, which started in the Albian in the Zlatne Basin on the southern side of the ridge and successively prograded to the north. They began with marly and shale-dominated variegated facies, passing into facies with a significant proportion of sandstones. West of Bialka River, the Pieniny Klippen Belt has a nappe structure. The sequence of nappes corresponds to that in the sedimentary area of the Alpine Tethys. The uppermost Zlatne Nappe contains deposits that originated in the southern part of the basin, while the other nappes contain rocks, laid down in the more northern areas.
Both tectonic and sedimentary processes (undersea mass movements) contributed to the formation of m & eacute;langes in the Pieniny Klippen Belt (PKB). The name Klippen Belt comes from the presence of "Klippen" (German for "cliffs") in this structure, i.e., elements that contrast in elevation with the surroundings. The "klippen" that are harder and more resistant to erosion are located among less resistant clastic formations, i.e., sandstones, mudstones, and marls. These klippen are composed of limestone and siliceous rocks, deposited on the ridge and slope parts of the PKB basins. In contrast, the flysch complexes, containing sandstones, mudstones, and marls, were deposited in the deeper parts of these basins. Some of the klippen are olistoliths, i.e., homogeneous or complex rock blocks of various sizes that were moved by gravity to the deeper zones of flysch basins. Other klippen entered the flysch formations as a result of tectonic deformations that took place during orogenic movements. Collisions and relative shifting of lithospheric plates resulted in the formation of the structure of the PKB, the western segment of which takes the form of a flower structure, bounded on both sides by deep faults. After uplift, the PKB was subjected to erosion processes, which led to the removal of the less durable complexes to reveal the shallower limestone blocks, which today form the klippen, clearly visible in the landscape.
