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EN
The Polish Geological Institute – National Research Institute (PGI – NRI), in cooperation with AGH University of Science and Technology in Krakow carried out the project of new geopark in Poland – “Wisłok Valley – The Polish Texas”. It is located in the Polish Outer Carpathians (SE part of Poland). Oil fields, mineral water, nappe tectonics and other geological components of the Outer Carpathians constitute important elements of the geodiversity of this region. The area is located in the Krosno neighbourhood and encloses a zone of about 1000 km2. The Iwonicz-Zdrój – Rymanów-Zdrój SPA region is also included in the research area. It covers 20 municipalities of the Podkarpackie province. For the project of the Geopark, a geotouristic map, geosites, geological-educational paths, website, advertising brochures, geological-educational tables and a movie were made, which promote geotourism. The final product will be targeted at regional and local public administration bodies, national and landscape Parks, the State Forests National Forest Holding and local tourist organizations.
PL
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy we współpracy z Akademią Górniczo-Hutniczą w Krakowie zrealizował projekt nowego geoparku w Polsce „Dolina Wisłoka – Polski Teksas”. Ma się on znajdować w Karpatach zewnętrznych. Złoża ropy naftowej, wody mineralne, tektonika płaszczowinowa i inne geologiczne cechy Karpat zewnętrznych składają się na georóżnorodność tego rejonu. Obszar tego opracowania obejmował ponad 1000 km2 w rejonie Krosna włączając w to również teren uzdrowisk Iwonicza-Zdroju i Rymanowa Zdroju. Projekt ten objął swym zasięgiem 20 gmin województwa podkarpackiego. W ramach projektu wykonano mapę geologiczno- turystyczną, udokumentowano ponad 150 geostanowisk i zaprojektowano dziewięć ścieżek geologiczno-edukacyjnych. Przygotowano też dwa foldery, 12 tablic geologiczno-edukacyjnych, zaprojektowano stronę internetową o projekcie oraz nakręcono film promocyjny. Produkt końcowy skierowany jest do wykorzystania w promocji regionu do samorządów lokalnych, parków krajobrazowych i narodowych, lasów państwowych oraz lokalnych organizacji turystycznych.
EN
Part of the Oxfordian carbonate buildups in the southern part of the Kraków Upland is developed as pseudonodular limestones, which represent segment reefs. These limestones are composed of connected, rounded-oval to subangular carbonate pseudonodules. The pseudonodules, densely packed within the limestone, fall out easily under mechanical stress. The recently observed texture of pseudonodular limestones resulted from two stages of chemical compaction. During the first stage, in the Late Jurassic, high-amplitude and low-amplitude stylolites and dissolution seams were formed. The sites particularly favourable for the development of high-amplitude stylolites were the boundaries between already lithified fragments of the laminar, rigid microbial-sponge framework. The low-amplitude stylolites formed mainly in the intercalated wackestone-packstone, which was lithified somewhat later; hence, the dissolution seams originated at the contacts between the rigid microbial-sponge framework and the wackestonepackstone. After Early Cretaceous erosion, which decreased the burial load, Late Cretaceous sedimentation enabled the renewal of pressure dissolution. Thus, some low-amplitude stylolites evolved into dissolution seams. In stylolites composed of both low- and high-amplitude segments, dissolution proceeded at the bases of interpenetrating high-amplitude stylolite columns, with the simultaneous transformation of low-amplitude stylolite segments into dissolution seams. These seams, which formed at the initial stage of chemical compaction, were subjected in turn to further pressure dissolution, giving rise to the formation of horsetail structures. The vertical stress field, which triggered the pressure dissolution processes, presumably resulted in the formation of high-angle and vertical incipient tension gashes. At the beginning of the processes, these gashes remained closed. In the Cenozoic, under the extensional regime generated by overthrusting Carpathian flysch nappes, some high-angle and vertical dissolution seams and low-amplitude stylolites opened up, forming deformed dissolution seams and deformed stylolites. Under the same conditions, the high-angle and vertical tension gashes opened up as well. Subsequently, during the exposure period, unloading fractures developed, partly as a result of the opening of some subhorizontal and horizontal dissolution seams and stylolites. The unloading fractures, along with the already existing vertical and high-angle tension gashes, formed the network changing the limestone into pseudonodules of various shapes and sizes. The open spaces between the limestone fragments became local conduits for karst waters.
EN
A spectacular epigenetic silicification was encountered in the Oxfordian bedded limestones exposed in the Sokole Hills situated in the Kraków-Częstochowa Upland. The main epigenetic mineral is microcrystalline quartz accompanied by minor goethite, hematite, barite, galena and sphalerite. Locally, the mineralized limestones reveal Pb and Cu contents exceeding over 150 times the background values of these metals in unmineralized limestones. The epigenetic mineralization of the bedded limestones was probably a two-stage process. During the first, Early Cretaceous stage, silicified limestones formed at the erosional surface of a denuded carbonate complex. Such silicification greatly limited the progress of the first karstification phase of the Upper Jurassic carbonates initiated in the Hauterivian. The sources of silica accumulated in the limestones were descending solutions enriched in silica derived from the weathering zone. This silicification affected the topmost part of the Upper Jurassic massive limestones and the deeper portions of the bedded limestones along the fracture systems and stylolites. Early Cretaceous tectonic activity generated new dislocations and re-opened the existing faults, which were subsequently filled with permeable Albian quartz sands. These openings became the migration pathways for ascending, warm, relict, sulphide-carrying hydrothermal solutions at the second formation stage of the epigenetic mineralization. The newly supplied silica from the Albian sands precipitated on the silicified limestones and, as concentric rims, on brecciated, early diagenetic cherts. The second-stage mineralization proceeded under phreatic conditions, presumably close to a fluctuating mixing zone of ascending, warm hydrothermal solutions and descending cold groundwaters. The brecciated cherts acting as silica crystallization nuclei indicate that the last mineralization stage probably followed the final phase of Cenozoic faulting.
EN
The Upper Jurassic carbonates exposed in the southern part of the Kraków-Częstochowa Upland are well known for their significant facies diversity related to the presence of microbial and microbial-sponge carbonate buildups and bedded detrital limestone in between. Both the buildups and detrital limestones revealed differential susceptibility to compaction which, apart from differential subsidence of the Palaeozoic basement and synsedimentary faulting, was one of the factors controlling seafloor palaeorelief in the Late Jurassic sedimentary basin. The compaction of the detrital limestones has been estimated with an experimental oedometric method in which specially prepared mixtures made of ground limestones from a quarry in the village of Żary were subjected to oedometer tests. The diameters of the detrital grains and their percentages in the limestones were determined by microscopic examinations of thin sections. The diameters were assigned to predetermined classes corresponding to the Udden-Wentworth scale. The rock samples were then ground down to the grain sizes observed in thin sections. From such materials, mixtures were prepared of grain size distributions corresponding to those observed in thin sections. After adding water the mixtures were subjected to oedometer tests. Analysis of the compression of such mixtures under specific loads enabled preparation of a mathematical formula suitable for the estimation of mechanical compaction of the limestone. The obtained values varied from 27.52 to 55.53% for a load corresponding to 300 metres burial depth. The most significant effect of mechanical compaction was observed for loads representing only 2 metres burial depth. Further loading resulted in a much smaller reduction in sample height. The results of the oedometer tests cannot be used directly to determine compaction of the detrital limestones. Mainly because microscopic observations of thin sections of the experimental material show that chemical compaction was also an important factor influencing thickness reduction of the limestones.
EN
The Upper Oxfordian microbial-sponge agglutinated to open-frame reef complex of the Zegarowe Crags in the Kraków-Częstochowa Upland originated upon an elevation of the Late Jurassic stable northern shelf of the Tethys. This elevation was formed, owing to a local decrease in subsidence rate during Jurassic time, induced by the presence of a Palaeozoic granitoid intrusion in the shelf substratum, and Late Jurassic, synsedimentary tectonics, which controlled the topography of the sea bottom. The Zegarowe Crags (Skały Zegarowe) complex at the top contains microbial laminites, composed of peloidal and agglutinated stromatolites, and intercalations of grainstones with indeterminable, favrenoid coprolites, occurring in large numbers. The development of stromatolites was associated with low nutrient availability. In contrast, the periodic activity of crabs, the main producers of the coprolites, forming the coprolitic grainstone intercalations, indicates periods, when nutrients were abundant in the sea water. The nutrinets most likely were associated with the occurrence of clouds of suspended matter, induced by gravity flows, generated by active, synsedimentary tectonics. The results of isotopic studies do not support the presence of warm, mineralizing solutions, connected with synsedimentary tectonics during development of the Zegarowe Crags complex in the Late Jurassic.
6
Content available remote Wybrane metody szacowania kompakcji w osadach węglanowych
PL
W artykule przedstawiono wybrane metody badań nad stopniem kompakcji osadów węglanowych, umożliwiając ich weryfikację oraz znaczenie. Ogólnie, proces kompakcji można podzielić na kompakcję mechaniczną (fizyczną) i chemiczną. Szacowanie stopnia kompakcji jest przydatne m. in. do rekonstrukcji pierwotnej miąższości osadów. Rekonstruując pierwotną miąższość osadów, stosuje się różne wskaźniki i metody. Dokonuje się tego m. in. w oparciu o obserwacje makroskopowe, mikroskopowe oraz pod mikroskopem skaningowym. Makroskopowo stopień kompakcji ocenia się sumując miąższości osadu rozpuszczonego wskutek stylolizacji. Mikroskopowo ocenia się stopień deformacji skamieniałości i ziaren, za pomocą mikroskopu elektronowego ocenia się zniekształcenia palynomorpha.
EN
This article presents exemplary researches on the degree of compaction on carbonate sediments, allowing them to discuss their significance. Generally, compactional processes may be divided into two categories: mechanical (physical) and chemical. Knowledge about the degree of compaction is helpful e. g. in reconstruction of the primary thickness. The degree of compaction is measured by several methods and indicators. To estimate the degree of compaction, macroscopic and microscopic examinations as well as a scanning electron microscope (SEM) are applied. Macroscopically, the degree of compaction is calculated by summing the thicknesses of sediments that had been dissolved by the stylolization processes. Microscopically, the degree of compaction is estimated on the base of observations on fossils and grains deformations and the SEM method- palynomorpha deformations.
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