Wyniki wyszukiwania - Biblioteka Nauki

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Biostratigraphy, magnetostratigraphy, C and O isotope distribution around the J/K boundary, the Brodno section (Kysuca Unit of the Pieniny Klippen Belt)

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Michalik J. , Rehakova D. , Halasova E. , Lintnerova O.

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tom Vol. 4, no. 1

190-191

EN

Detailed litho- and biostratigraphy of the Brodno section in contact zone of the Outer and the Central Western Carpathians was given by Michalík et al. (1990), VaĘíçek et al. (1992). Kimmeridgian and Tithonian condensed sequence of red nodular limestones (the Ammonitico Rosso facies) is referred to as the Czorsztyn Limestone Fm. Calcareous dinoflagellates Carpistomiosphaera borzai and Stomiosphaera moluccana indicate its Kimmeridgian age; Parastomiosphaera malmica, Carpistomiosphaera tithonica and Colomisphaera pulla indicate Early Tithonian age; calpionellids Chitinoidella boneti, Praetintinnopsella andrusovi, Crassicollaria intermedia, Crassicollaria brevis, Crassicollaria parvula, Crassicollaria colomi, confirm Middle to Late Tithonian age of this formation. Lower Berriasian part of this succession is represented by pale biomicritic wackestone (Pieniny Limestone Fm) with abundant Calpionella alpina. Strong subsidence and acceleration of “planktic rain” of nannofossils started on the Early/Middle Tithonian boundary where Polycostella beckmannii appeared. Helenea chiastia together with first small nannoconids are typical of the Middle and Late Tithonian. The Late Tithonian interval was specified by the FO of Rotelapillus laffitei and Litraphidites carniolensis. The Tithonian/Berriasian boundary was characterized by the FO of Nannoconus wintereri together with small nannoconids and by the FO of Nannoconus steinmanni minor. There is good correlation between the calcareous nannofossils distribution and the magnetostratigraphic zonation (HouĘa et al. 1996). In the M 20-M 19 interval, two distinct nannoevents were recognized: the dominance of Polycostella beckmannii (Chitinoidella Zone) and the appearance of calcareous nannofossil association with Helenea chiastia (Crassicolaria Zone). Carbon isotope curve from bulk carbonates of the J/K boundary sequence shows smooth trends resulted from equilibrated measure of bio-productivity and organic matter burial. The ä13C value ranges from 1.3 to 1.5‰ (PDB). The authentic character of the limestone record is underlined by relative high and conservative ä18O values (-2.27 to -0.88) of the same beds. These signals can be useful in global stratigraphic correlation in deep water carbonates.

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Skala magnetostratygraficzna dla utworów retu i wapienia muszlowego ze Śląska i północnej części Gór Świętokrzyskich

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Nawrocki J. , Szulc J.

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2000

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tom Vol. 48, nr 3

236-238

PL

Syntetyczną skalę zmian polarności zestawiono opierając się na kierunkach paleomagnetycznych uzyskanych ze 108 próbek, które pobrano z odsłonięć na Śląsku Opolskim, w okolicach Chrzanowa oraz w północnej części Gór Świętokrzyskich. Skalę tę skorelowano z wcześniej opracowaną (Muttoni i in., 1998) skalą dla środkowego triasu z obszaru tetydzkiego. Z przeprowadzonej korelacji wynika, że utwory retu w całości należy paralelizować z olenekiem. Sedymentacja utworów wapienia muszlowego na obszarze śląskim rozpoczęła się już w najwyższej części oleneku. Na północnym obrzeżeniu Gór Świętokrzyskich ostatnie ogniwa wapienia muszlowego należy wiązać z wczesnym fassanem. Począwszy od późnego fassanu na obszarze tym osadzały się utwory facji kajpru.

EN

A total of 132 samples of Roetian and Muschelkalk sediments from Silesia and northern part of the Holy Cross Mts were paleomagneticaly studied. Composite polarity scale has been constructed using a set of characteristic directions isolated in 108 samples. This scale has been compared with the Middle Triassic magnetostratigraphic scheme established in the Tethyan realm (Muttoni et ah, 1998). The comparison suggests that the whole Roetian should be included into the Olenekian. In the Silesia area, the Muschelkalk sedimentation started already in latest Olenekian time. The Muschelkalk sedimentation ceased in the northern margin of the Holy Cross Mts as early as in early Fassanian time and no more later as in late Fassanian time the other ojfshore parts of the Polish basin. The established magnetostratigraphic scheme along with the earlier constructed sequence stratigraphical framework (Szulc, 1999) enables a reliable chronostratigraphical correlation of the Middle Triassic throughout the entire Germanic basin

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Biostratigraphy of the Santonian in the SW margin of the Holy Cross Mountains near Lipnik, a potential reference section for extra-Carpathian Poland

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Remin Z.

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2004

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tom Vol. 54, no. 4

587-596

EN

The set of outcrops near the village of Kije, on the SW margin of the Holy Cross Mountains provides a nearly complete Santonian succession that has a great potential to become a Santonian reference section in Poland. The Coniacian/Santonian boundary is defined here by the first occurrence (FO) of the inoceramid bivalve species Cladoceramus undulatoplicatus (ROEMER 1852). The uppermost Santonian is characterized by common Sphenoceramus patootensiformis (SEITZ 1965). The top of the stage (and the base of the Campanian Stage) is documented by the last occurrence (LO) of the crinoid species Marsupites testudinarius (SCHLOTHEIM 1820). The substage division of the Santonian is based on inoceramids, with the lower boundary of the Middle Santonian indicated by the LO of Cladoceramus undulatoplicatus and the base of the Upper Santonian by the FO of representatives of Cordiceramus muelleri (PETRASCHECK 1906) group.

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Faunal and floral distribution, biostratigraphy, cyclostratigraphy and magnetostratigraphy of the T/J boundary

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Michalík J. , Soták J. , Ruckwied K. , Götz A. , Grabowski J.

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tom Vol. 4, no. 1

292-292

EN

The Rhaetian and Hettangian sequence in the Zliechov Basin, Western Carpathians, comprises records of several environmental crises which could contributed to the global Triassic/Jurassic Boundary Events. The Upper Triassic Fatra Formation is characterized by bioclastic limestones and fine-grained clastics overlain by dark claystones with intercalated sandstones (Cardinia Sandstein) of the Kopieniec Formation. The diversity of benthic fauna decreased at the base of the "Transition Beds" - the uppermost member of the Fatra Formation. The fauna comprises important index forms of bivalve molluscs (Chlamys valoniensis), corals, brachiopods (Austrirhynchia cornigera) and foraminifers (Triasina hantkeni, etc.). The palynofacies of the entire succession is dominated by terrestrial components and by high amount of phytoclasts. The few marine organic particles indicate a very shallow marine depositional environment. The palynomorph assemblage of the Fatra Formation is characterized by numerous specimens of Ricciisporites tuberculatus. The marine fraction of the lower part of the section is dominated by the dinoflagellate cyst Rhaetogonyaulax rhaetica. The palynomorph assemblage of the Kopieniec Formation is characterized by a significant increase of trilete laevigate spores, mainly Deltoispora spp. and Concavisporites spp. The dinoflagellate cyst Dapcodinium priscum replaces Rhaetogonyaulax rhaetica in the marine fraction. These changes may be caused by a regression at the Triassic/Jurassic boundary and by an important fresh water input. The boundary between the Fatra and the Kopieniec formations is sharp, denoted by sudden termination of carbonate sedimentation followed by non-carbonate Boundary Clay of the Kopieniec Formation. Magnetostratigraphic record is in procession, it is hampered by complicated pattern of geomagnetic reversals at the end of the Triassic and at the beginning of the Jurassic period.