Integrated stratigraphy of the upper Lower - lower Middle Cenomanian of northern Germany and southern England
WILMSEN M.
Institut für Geologie und Paläontologie der Universität, Pleicherwall 1, D-97070 Würzburg, Germany.
m.wilmsen@mail.uni-wuerzburg.de
ABSTRACT: A high-resolution stratigraphic calibration of the upper Lower (upper Mantelliceras dixoni Zone) and lower
Middle Cenomanian (Cunningtoniceras inerme Zone and lower Acanthoceras rhotomagense Zone) based on
an integrated analysis of macrofossil biostratigraphy, event, cyclo-, stable-isotope and sequence stratigraphy
of northern German and southern England key sections is presented. Classic event stratigraphy has a good
potential in refining biostratigraphic correlations as most of the classic bioevents are isochronous within the
integrated stratigraphy. Many lithological event beds such as marker marls can be incorporated into the
cyclo- and sequence stratigraphic framework, explaining their significance in interregional correlation. The
best stratigraphic resolution provides the cyclostratigraphy based on the typical Cenomanian marl-limestone
couplets and their stacking pattern, inferred to reflect orbital forcing of the Milankovitch frequency
band: detailed bed-by-bed correlation of couplets (precession cycle, ca. 20 kyr) allows a stratigraphic calibration
within ~10 kyr time slices. Conspicuous marker marl beds embrace bundles of ~five couplets and
are related to the short eccentricity (100 kyr) cycle. However, for the upper Lower Cenomanian (dixoni
Zone) it appears that the existing couplet scale is incomplete. Sequence stratigraphic analysis demonstrates
that the investigated interval comprises the maximum flooding and highstand interval of an Early
Cenomanian sequence, capped by a significant late dixoni Zone sequence boundary, followed by uppermost
Lower to Middle Cenomanian lowstand and transgressive deposits grading into a Middle Cenomanian maximum
flooding zone ("calcimetry break"). Carbon stable-isotope values are stable around 2‰ vs. V-PDB
within the mid- and late dixoni Zone, related to equilibrium conditions during maximum flooding and highstand
conditions of sea-level. The latest Early to earliest Middle Cenomanian sea-level fall and lowstand
was accompanied by a negative δ13C excursion of ca. 0.4 ‰ in couplets B34-B40 (Lower-Middle
Cenomanian boundary isotope Event, LMCE, new name) followed by a rise of 0.4-0.6‰ δ13C in couplets
B41-C2 during the early transgressive systems tract (Middle Cenomanian δ13C excursion MCE 1). These
observations support the interpretation that the δ13C signal is a good proxy for (eustatic) sea-level changes.
The LMCE is suggested as a proxy marker for the base of the Middle Cenomanian Substage.
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Middle Permian rugose corals from the Kapp Starostin Formation, South Spitsbergen (Treskelen Peninsula)
CHWIEDUK E.
Institute of Geology, Adam Mickiewicz University, Makow Polnych str. 16, PL-61-606 Poznan, Poland.
chwieduk@amu.edu.pl
ABSTRACT: The rugose corals from the topmost part of the Kapp Starostin Formation on the Treskelen Peninsula,
South Spitsbergen, are described. The collection consists of 22 specimens, representing the genera
Calophyllum, Allotropiochisma and Euryphyllum. These solitary and non-dissepimented taxa, considered
to be cold-water forms, are representatives of the Calophyllum Province of the Cordilleran-Arctic-
Uralian Realm, and confirm a biogeographical connection between Alaska, Ural Mts., Central
European Basin, Sverdrup Basin, and Arctic Canada in the Middle Permian.
In southern Spitsbergen the Kapp Starostin Formation yields apparently the latest representatives
of the Rugosa in the whole Hornsund region, dated to the Guadalupian and probably to the Wordian.
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Cavitation erosion – a possible cause of the mass loss within thrust zones in the Tatra Mts., Poland
JUREWICZ E.1, GIREN B2, STELLER J.2
1Faculty of Geology, University of Warsaw, Al. Zwirki i Wigury 93, PL-02-089 Warsaw, Poland.
edyta.jurewicz@uw.edu.pl
2The Szewalski Institute of Fluid Flow Machinery, Polish Academy of Sciences, ul. Fiszera 14, PL-80-952 Gdansk, Poland.
giren@imp.gda.pl
steller@imp.gda.pl
ABSTRACT: In the Tatra Mts., thrust-napping and shearing were multi-stage re-activated processes. Their cyclic character
was determined by increases and decreases in pore fluid pressure. During each cycle, new parts of
the rheologically heterogeneous wall-rock were selectively destroyed due to hydraulic fracturing, brecciation
and mylonitization, and moved out as a solution and/or suspension. As a result of these processes,
including pressure solution, considerable mass loss could have taken place. All these processes took
place under the considerable influence of fluids. In this paper we consider the possible contribution of
cavitation erosion to mass loss processes. Displacement along an uneven thrust surface could create
chambers filled with fluid and sudden falls in local pressure promoting the inception of cavitation.
Cavitation damage, mainly mechanical in nature, could act synergistically with slurry abrasion and pressure
solution processes.
Our work is of a hypothetical character. To prove the possibility of cavitation erosion within shear
zones in the Tatra Mts. we conducted an experiment to show the low resistance of rock samples to cavitation
erosion. We also discuss and characterize the conditions essential to induce cavitation within thrust
zones at the base of nappes.
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Large Chirotheriidae tracks in the Early Triassic of Wiory, Holy Cross Mountains, Poland
NIEDZWIEDZKI G. 1,2, PTASZYNSKI T.3
1Department of Paleobiology and Evolution, Faculty of Biology, Warsaw University, S. Banacha Str. 2, PL-02-097 Warszawa, Poland.
grzegorzniedzwiedzki@yahoo.com
2Paleontological Section, Museum of Nature and Technology at Starachowice, Wielkopiecowa Str. 1, PL-27-200 Starachowice, Poland.
3Stronska Str. 1/12, PL-01-461 Warszawa, Poland.
TPtasz@interia.pl
ABSTRACT: Very large chirotheriid tracks have been discovered in the Early Triassic Wiory Formation
(=Labyrinthodontidae and Hieroglyphic Beds), middle part of the Middle Buntsandstein, exposed at
Wióry in the northeastern part of the Holy Cross Mountains (central Poland). Hitherto, six small and
medium-sized chirotheriid tracks from the Wióry locality have been described. In the present paper two
ichnotaxa are proposed: Synaptichnium senkowiczowae ichnosp. nov. and Brachychirotherium kalkowensis
ichnosp. nov. Their presumed trackmakers, large Early Triassic (Olenekian) Archosauriformes
(Proterosuchidae, Erythrosuchidae), about 5-7 m long, are unknown from the osteological record of this
age worldwide. The newly described ichnotaxa represent the oldest known record of large chirotheriid
tracks in the Middle Buntsandstein of Poland. The presence of large chirotheriid tracks in the upper
part of the Early Triassic deposits is very important for the understanding of the evolution and radiation
of early Archosauromorpha, as well as for reconstructing Early Triassic terrestrial palaeoecosystems.
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Minute patellogastropods (Mollusca, Lottiidae) from the Middle Miocene of Paratethys
ANISTRATENKO O.1,3, ANISTRATENKO V.2,3
1Institute of Geological Sciences of National Academy of Sciences of the Ukraine, O. Gontchara Str., 55-b, UA-01601, Kiev, Ukraine
2I. I. Schmalhausen Institute of Zoology of National Academy of Sciences of the Ukraine, B. Khmelnitsky Str., 15, UA-01601, Kiev, Ukraine
3Institute of Geological Sciences of Polish Academy of Sciences, Geological Museum, Senacka Str., 1, PL-32-002, Kraków, Poland.
anistrat@ln.ua
anistrat@rambler.ru
ABSTRACT: The protoconch and teleoconch morphology of lottiid patellogastropods that inhabited the Central and
Eastern Paratethys in the Badenian and Sarmatian are described and illustrated. Eleven species belonging
to the genera Tectura, Blinia, Flexitectura and Squamitectura are considered as valid: Tectura laevigata
(EICHWALD, 1830), T. compressiuscula (EICHWALD, 1830), T. zboroviensis FRIEDBERG, 1928, T. incognita
FRIEDBERG, 1928, Blinia angulata (D'ORBIGNY, 1844), B. pseudolaevigata (SINZOV, 1892), B. reussi
(SINZOV, 1892), B. sinzovi (KOLESNIKOV, 1935), Flexitectura subcostata (SINZOV, 1892), F. tenuissima
(SINZOV, 1892), and Squamitectura squamata (O. ANISTRATENKO, 2001). The type material of species
introduced by W. FRIEDBERG (1928) is revised and lectotypes are designated for T. zboroviensis and T.
incognita. The taxonomic status and position of this group of species is discussed. Data on palaeogeographic
and stratigraphic distribution, variability and the relationships of Middle Miocene Lottiidae
GRAY, 1840 are presented.
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The application of geomorphological analysis of the Vistula River, Poland in the evaluation of the safety of regulation structures
FALKOWSKI T.
Faculty of Engineering and Environmental Science Warsaw Agricultural University,Nowoursynowska Str. 159, PL-02-776 Warszawa, Poland.
tomasz_falkowski@sggw.pl
ABSTRACT: Investigations within the channel zone of the Middle Vistula River have shown the presence of protrusions
of the alluvial basement composed of deposits resistant to erosion. On their surface, and in the basal
part of the present-day channel facies, occur residual lags composed of gravels and pebbles. These lags
indicate exposure of the surface of the alluvial basement in the channel bottom during high-water stages.
Protrusions of the resistant alluvial basement often show a complex morphology which influences the
course of the thalweg, particularly during floods. The constant trend to concentrate the high-water
stream may be the reason for the damage to regulation and flood control system structures. The concentration
of the high-water flow causes the formation of specific erosional and depositional forms on the
terrace surface. Such forms can thus serve as indicators of the zones of alluvial basement protrusions. The
paper presents examples of three reaches of the Middle Vistula River Valley (The Mid-Polish Lowlands).
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