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1

Jurassic unconformities in the High-Tatric succession, Tatra Mountains, Poland

Jezierska A., Łuczyński P.

Geological Quarterly

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2016

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Vol. 60, No. 2

273--290

EN

During the Triassic/Jurassic boundary interval and in the Jurassic, the Triassic carbonate platforms occupying the northern shelf of the Western Tethys were subjected to disintegration. Record of these processes in the Alpine-Carpathian area is incomplete and contains a number of stratigraphic gaps. In the High-Tatric succession of the Tatra Mountains (Central Western Carpathians) stratigraphic gaps expressed by unconformity surfaces occur between the Triassic and the Middle Jurassic. In particular areas, the Triassic is directly overlain by the Dudziniec Formation (Sinemurian-Bajocian), the Smolegowa Formation (Bajocian), the Krupianka Formation (Bathonian) or the Raptawicka Turnia Formation (Callovian-Hauterivian). The occurrence of Bajocian and Bathonian deposits is limited to isolated lenticular bodies or to infillings of neptunian dykes penetrating the Triassic. Spatial relations between particular Jurassic lithosomes and the occurrence of stratigraphic gaps between particular units allow discerning four main unconformities. In the stratigraphical order these are: base of the Dudziniec Format ion (erosional unconformity), base of the Smolegowa Formation (penacordance or parat conformity), base of the Krupianka Format ion (erosional unconformity) and base of the Raptawicka Turnia Formation (drowning unconformity). Following episodes of erosion modified the previously developed unconformity surfaces, which resulted in complex modern architecture of the Triassic/Jurassic contact, as well as between particular Jurassic formations.

2

Monitorowanie procesu badawczego jako forma zapobiegania potencjalnym niezgodnościom

Dymarek E., Pabian-Macina M., Orzech Ł.

Problemy Jakości

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2009

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R. 41, nr 12

16-22

EN

The problems concerning potential unconformities that can be caused by unwanted events during realization of research projects were presented in the paper. A significant role of monitoring the procedures in the company was pointed out as well as suggestions for the measures to be undertaken for elimination the potential and found unconformities were given. Due to extensity of the problem the paper focuses on analysis of the projects of research, designing certification, prototype testing etc. character. The paper has been prepared on the basis of many years of audits practice.

3

Karst processes and time

Bosak Pavel

Geologos

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2008

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Vol. 14, No. 1

19--36

EN

Karst evolution depends particularly on the time available for process evolution and on the geographical and geological conditions of the exposure of the rock. The longer the time, the higher the hydraulic gradient and the larger the amount of solvent water entering the karst system, the more evolved is the karst. In general, stratigraphic discontinuities directly influence the intensity and extent of karstification. Unconformities influence the stratigraphy of the karst through the time-span that is available for subaerial processes. The end of karstification can also be viewed from various perspectives. The definite end occurs at the moment when the host rock, together with its karst phenomena, has completely been eroded/denuded. Karst forms of individual evolution stages (cycles) can also be destroyed by erosion, denudation and abrasion without the necessity of the destruction of the whole succession of karst rocks. Temporary and/or final interruption of the karstification process can be caused by the “fossilisation” of the existing karst phenomena due to loss of hydrological activity. The shorter the time available for karstification, the greater is the likelihood that karst phenomena are pre-served in the stratigraphic record. While products of short-lived karstification on shallow carbonate platforms can be preserved by deposition during a immediately succeeding sea-level rise, products of more pronounced karstification can be destroyed by various geomorphological processes. The longer the duration of subaerial exposure, the more complex these geomorphological agents are.

PL

Rozwój procesów krasowych jest funkcją czasu oraz geograficznych i geologicznych warunków odsłonięcia skał. Im dłuższy czas ekspozycji skał na czynniki meteorologiczne, większy gradient hydrauliczny, większa ilość wody w układzie krasowym, tym bardziej zaawansowana jest ewolucja krasu. Intensywność i zasięg krasowienia zależą też od niezgodności stratygraficznych, czyli przerw w sedymentacji. Zakończenie rozwoju procesów krasowych rozpatrywać można w różnych kategoriach. Za definitywny koniec należy uznać czas, gdy skały podlegające krasowieniu ulegną całkowitej denudacji/erozji. O wiele częściej bywa, że zniszczeniu ulegają tylko formy krasowe, natomiast niżej położone skały systemu krasowego pozostają zachowane. Okresowe lub całkowite przerwanie procesów krasowych może być spowodowane przez fosylizację systemu krasowego, która zachodzi w efekcie zaniku aktywności hydrologicznej. Taka fosylizacja może być spowodowana przez metamorfizm, transgresję morską, pogrzebanie osadami kontynentalnymi lub skałami wulkanicznymi, w wyniku np. ruchów tektonicznych, zmiany klimatu, itp. Im krótszy jest czas krasowienia, tym większe jest prawdopodobieństwo zachowania śladów procesów krasowych. I tak, produkty krótkookresowej karstyfikacji na płytkich, okresowo wynurzanych platformach węglanowych mogą ulegać łatwemu zachowaniu poprzez pogrzebanie osadami deponowanymi podczas podniesienia poziomu morza. Natomiast efekty długotrwałego krasowienia bywają często niszczone przez późniejsze degradacyjne procesy geomorfologiczne. Charakter tych ostatnich jest tym bardziej skomplikowany, im dłużej trwa subaeralna ekspozycja skrasowiałych skał.

4

Late Cretaceous unconformities in the Subhercynian Cretaceous Basin (Germany)

Voigt T., Eynatten H. von, Franzke H.-J.

Acta Geologica Polonica

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2004

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Vol. 54, no. 4

673--694

EN

In the Subhercynian Cretaceous Basin, six Upper Cretaceous angular unconformities can be observed. The first unconformity, at the base of the Cenomanian transgressive deposits, is not related to the development of the basin. While the second (Lower to Middle Coniacian) unconformity is almost limited to the northern basin margin, four unconformities are developed at the Harznordrand Thrust and span the short period from the Middle Santonian to the late Early Campanian (about 3 Ma). The intra-Coniacian unconformity at the northern basin margin proves tilting of the basin floor to the south-east and is possibly related to the development of the thrust too. The Santonian to Campanian unconformities at the Harznordrand Thrust reflect the formation of a continuously growing fault-propagation fold. Deposition above unconformities occurred when the rate of eustatic sea-level rise exceeded thrusting rate.Transgressions occurred in the earliest Middle Santonian, in the Late Santonian (intra-Marsupites Zone), in the earliest Campanian (granulataquadrata Zone) and in the late Early Campanian (Offaster pilula Zone). The ages of unconformities correlate well with the transgressive pulses proved in Western and Middle Europe and are not related to discrete deformational events.