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Small-scale cyclic deposition in the Frasnian (Upper Devonian) of the Holy Cross Mountains, Poland

Vierek A.

Geologos

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2014

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Vol. 20, No. 4

239--258

EN

In sections exposing Frasnian limestones at five outcrops in the Holy Cross Mountains, five lithofacies (L1 to L5) that represent upper slope to basinal environments are identified. These lithofacies are characterised by dark-coloured micritic limestones–marly shale couplets with many light-coloured intercalations of fine- to coarse-grained limestones (= event beds). This lithofacies pattern characterises mostly low-energy domains punctuated by storm episodes. In addition, these upper-slope to basinal lithofacies are arranged into small-scale, coarsening-upward beds and cycles. The cycles are locally composed of fining/thinning-upward beds. The small-scale cycles have a calculated duration of 19 to 42 kyr. The differential thickness of beds and cycles within and between sections was probably caused by differential subsidence and local tectonics. Possible evidence of tectonic activity is also related to a difference in number of cycles recorded in the time-equivalent sections. The recognised cyclicity shows sea-level fluctuations and a few deepening episodes. Some of them are correlated with the Timan global eustatic events. However, local tectonics and episodic subsidence may have played a significant role in recording brief deepening pulses. Thus, low-amplitude sea-level changes were major factors in platform generation and evolution in the Frasnian of the Holy Cross Mountains modified by local, block-related subsidence.

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A trail of storms imprinted in Triassic rocks on the touristic path: an example from Grodziec (Dąbrowa Basin, southern Poland)

Gawęda A., Vierek A.

Geotourism / Geoturystyka

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2012

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nr 1-2

51--58

EN

The Upper Silesia -Dąbrowa Basin is one of the highest industrially transformed regions in Europe. However, places of geotouristic value are still preserved and should be protected. One of them is the abandoned "Kamionka" quarry and nearby St. Dorotahill, knownas "local Olympus" with historical monuments, located in the Grodziec district of Będzin. The profile of Triassic limestones, dolomitized limestones and marly dolomites belong to so called Gogolin Beds and represent the sedimentation typical of sea transgression with numerous changes in water energy, up to stormy sedimentation, imprinted in rock textures and sedimentary structures. Both proximal and distal tempestites are found here. Local bioturbations are indicative for breaks in storm activity and low-energy sedimentation. In general, the carbonate sediments of Grodziec district were formed in shallow basin, on the carbonate ramp, influenced by storms and/or bottom currents. The link between the history of that area, geomorphology and geological features makes that area of special importance for geotourism.

PL

Basen śląsko-dąbrowski należy do najbardziej uprzemysłowionych, a przez to silnie zmienionych w wyniku działalności człowieka, rejonów Europy. Miejsca o wartości geoturystycznej z racji swej rzadkości powinny być pod specjalną ochroną. Jednym z takich miejsc jest nieczynny kamieniołom „Kamionka" usytuowany blisko wzgórza św. Doroty, znanego także jako „Olimp zagłębiowski ", usytuowane w dzielnicy Będzina o nazwie Grodziec. Odsłaniający się w kamieniołomie profil triasowych wapieni, częściowo zdolomityzowanych i marglistych należy do tak zwanych warstw gogolińskich i reprezentuje cechy sedymentacyjne typowe dla transgresji morskiej. W osadach znaleźć można zapis teksturalny i strukturalny wielokrotnych zmian energii wód aż do sedymentacji sztormowej, z charakterystycznymi osadami tempestytów proksymalnych i dystalnych. Lokalnie obserwowane bioturbacje wskazują na przerwy w aktywności sztormowej i sedymentacji niskoenergetycznej. Sekwencje osadowe, odsłaniające się w Grodźcu, powstawały w płytkim basenie sedymentacyjnym, na rampie węglanowej, noszą cechy zarówno osadów sztormowych, jak i prądów dennych. Obszar Kamionki - wzgórza św. Doroty jest przykładem związków między budową geologiczna, geomorfologią oraz historią regionu i jest przez to obszarem o dużym znaczeniu geoturystycznym.

3

Charakterystyka sedymentologiczna górnej części warstw szydłóweckich

Vierek A.

Przegląd Geologiczny

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2008

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Vol. 56, nr 9

848-856

EN

The Givetian to Frasnian boundary interval in the N part of the Kielce region (Holy Cross Mts.) consists of dark-coloured shales, marls and micritic limestones defined as Szydłówek Beds. The upper parts of the Szydłówek Beds are well exposed in the Kostomłoty-Mogiłki and Górno-Józefka quarries. These sections are situated in Kostomłoty transitional facies zone between the shallow-water carbonate platform and the deeper Łysogóry basin. The uppermost parts of the Szydłówek Beds comprise many fine-grained intercalations: laminated calcisiltites, calcarenites, calcirudites and coquinas beds. The shales, marls and micritic limestones are hemipelagic deposits of deep, quiet and oxygen-depleted basin, whereas grained limestones correspond with shallower water and higher energy environment. Laminated calcisiltites and finer calcarenites originated in the environment below storm wave base and are interpreted as surge-like turbidity flows deposits. Thicker calcarenites, calcirudites, and coquinas beds were deposited about storm wave base and are interpreted as tempestites.

4

Storm-dominated deposition on a Frasnian carbonate platform margin (Wietrznia, Holy Cross Mts., Poland)

Vierek A.

Geological Quarterly

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2007

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Vol. 51, No 3

307-318

EN

The Wietrznia quarry in Kielce is situated between the shallow-water Devonian carbonate platform in the Kielce region and the deeper Łysogóry basin. This palaeogeographic setting affected carbonate sedimentation in Late Devonian times. The transitional facies of the Wietrznia Frasnian comprises two over lapping types of deposits: (1) micritic and marly limestone of shelf basin facies and (2) coarse-grained limestone of fore-reef facies. The first type includes laminated- and graded micritic limestone and modular limestone. The second includes intraformational conglomerates and breccias, and crinoidal limestone. The limestones in the middle Wietrznia Beds formed within storm wave basein a shal ow (possibly only a few tens of metres) sea that deepened eastwards. Storms are likely to have been the main cause of erosion and transport. In the western part of the quarry, proximal tempestites show evidence of amalgamation and cannibalism as do some high-energy flat-pebble conglomerates. With abating storm winds, finer-grained graded and laminated limestones accumulated. To ward the eastern part of the quarry, the high-energy effects of near-shore storm waves are less evident; the deposits there are transitional or more distal tempestites.

5

Uwagi o zawartości pierwiastków ziem rzadkich w wapieniach i dolomitach z okolic Krakowa

Vierek A.

Przegląd Geologiczny

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2005

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Vol. 53, nr 5

413--417

EN

Rare-earth elements (REE) were determined for the Upper Jurassic limestone and dolomites from the following outcrops: Góra OEw. Anny, Kostrze Quarry, Księża Góra, and Skały Twardowskiego. REE patterns are similar for all the investigated samples. Dolomites and limestone are enriched in light REE, they exhibit positive La anomalies, and negative Ce and Eu anomalies. Negative Ce and Eu anomalies are typical for oxidizing environments during dolomitization processes. Distinct enrichment in light REE comparing to heavy REE indi-cates that the sea water was not the only component of dolomitization fluids.

6

Dedolomityzacja w górnojurajskich skałach węglanowych z okolic Krakowa

Vierek A.

Przegląd Geologiczny

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2005

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Vol. 53, nr 2

156--161

EN

The Upper Jurassic limestones in the vicinity of Cracow underwent extensive dedolomitization process. Petrographic and cathodoluminescent analyses of carbonates in four test areas confirm the dedolomitization as have been developed with various intensity. The alteration of dolomite into calcite occurs as centripetal and centrifugal dedolomitization. Both processes lead finally to a complete disintegration of the dolomite crystals; calcite pseudomorphs after dolorhombs are the end products. These calcite pseudomorphs are abundant in limestones of St. Anna Mt. and in the Kostrze quarry, but are scarce in the Twardowski Cliffs area and in the outcrop of Księża Mt., which indicates a less advanced and slower dedolomitization process in the latter two areas. Most probably the initiation of dedolomitization started from the moment when a carbonate bank emerged from the sea water (Vierek, 2003); temperature of mixing fluids decreased considerably, whereas Ca 2+/Mg+- ratio in the same fluids increased.

7

Przejawy procesów metasomatycznych w wapieniach górnej jury z okolic Krakowa

Vierek A.

Przegląd Geologiczny

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2003

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Vol. 51, nr 6

507-516

PL

Przedmiotem badań są procesy dolomityzacji, którym lokalnie uległy wapienie górnojurajskie z okolic Krakowa. Badania prowadzono w czterech odsłonięciach: na Górze Św. Anny, w Kamieniołomie Kostrze, na Księżej Górze oraz w Skałach Twardowskiego. Celem badań była próba określenia czasu i warunków powstania dolomitów oraz wyjanienie mechanizmu dolomityzacji i charakteru wywołujących ją roztworów. W oparciu o cechy geochemiczno-petrograficzne sugeruje się powstanie badanych dolomitów w strefie mieszania wód morskich i meteorycznych (model Dorag), w srodowisku utleniającym, w warunkach płytkiego pogrzebania, z roztworów o względniepodwyższonej temperaturze, około 60o C. Czas tworzenia dolomitów zamyka się w przedziale najwyższa jura–kreda. W toku badań stwierdzono przejawy procesów rekrystalizacji, dedolomityzacji i sylifikacji.

EN

The zones of dolomitization within the Upper Jurassic limestones were studied in four outcrops: Góra Św. Anny, Kos trze Quarry, Księża Góra, and Skaty Twardowskiego. The study aimed to determine the time and the environment of dolomitization as well as to explain the mechanism of dolomitization and character of fluids. Petrografie studies and geochemical analyses proved that the origin of dolomites can be related to mixing zone of sea- and meteoric waters (mixed-water dolomitization model), under oxidizing and shallow burial conditions. Dolomitizingfluids reveal temperatures about 60°C. The results point to the age of dolomitization between the uppermost Jurassic and Cretaceous. Processes ofrecrystallization, dedolomitization and silicification have been identified.