Bajocian - Bathonian ammonite fauna of the Czorsztyn Unit, Pieniny Klippen Belt (Western Carpathians, Slovakia); its biostratigraphical and palaeobiogeographical significance
SCHLOGL J.1, RAKUS M.2, MANGOLD CH.3, ELMI S.3
1Department of Geology and Paleontology, Faculty of Sciences, Comenius University, Mlynska dolina - G,SK-842 15 Bratislava, Slovakia
schlogl@nic.fns.uniba.sk
2Geological Survey of Slovak Republic, Mlynska dolina 1, SK-817 04 Bratislava, Slovakia.
rakus@gssr.sk
3UMR 5125 Paléoenvironnement et Paléobiosphére, 2 rue Dubois, Université Claude Bernard Lyon1, 69 622 Villeurbanne Cedex, France
ABSTRACT: The Parkinsoni Zone of the Late Bajocian and the Zigzag, Aurigerus and Retrocostatum Zones of the Bathonian have
been identified on the basis of relatively highly diversified ammonite assemblages within seven ammonitico rosso sections
belonging to the Czorstyn Unit, Pieniny Klippen Belt. The ammonite fauna has features in common with both
the Mediterranean Province and the Sub-Mediterranean Province, containing abundant Phylloceratina and
Lytoceratina on the one hand, but numerous Parkinsonia on the other. Ammonites of Arabian affinities belonging to
the genus Micromphalites occur rarely in the Early Bathonian Zigzag Zone assemblage. Lytoceras joniaki, Lissoceras compressus and Cadomites (Polyplectites) minutus are proposed as new taxa.
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Dhahal structure: an example of transpression associated with the Dead Sea transform in Wadi Araba, Jordan
ATALLAH M.1, MUSTAFA H.1, EL-AKHAL H.1, AL-TAJ M.2
1Department of Earth and Environmental Sciences, Yarmouk University, Irbid-Jordan
2Department of Earth and Environmental Sciences, The Hashemite University, Zarqa-Jordan
ABSTRACT: The Dhahal Mountains located at the eastern margin of the northern Wadi Araba sinistral fault
represent an example of a transpression associated with the Dead Sea transform, which is a sinistral wrench fault. This structure was
formed as a result of right bending of the Humrat Fidan active sinistral fault, which is a parallel strand of the Dead Sea transform
located east of the main Wadi Araba fault. The fault bend caused uplift and squeezing of the Cretaceous and Tertiary rocks of the
transpression. Positive flower structures, folds, fault-bounded wedge-shaped pop-ups and reverse faults are the main structural
elements that characterized the Dhahal transpression. Folds are found as sets or as single anticlines and synclines. The major
trend of the fold axes is N50°; the principal stress axis (ó1) is perpendicular to this trend (N140°). This trend
deviates 26° anticlockwise from that of the Dead Sea stress system (DSS) (as obtained from fault slip data north of the
study area), which is responsible for the formation of the Dead Sea transform. Evidence of active uplift in the Dhahal
structure is provided by the sharp topography relative to the surrounding areas, and the low mountain front sinuosity
index of the western margin of the Dhahal mountains.
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Morphology and taxonomy of Late Badenian to Sarmatian Mohrensternia (Gastropoda: Rissooidea) of the Central Paratethys
ANISTRATENKO V.
I.I. Schmalhausen Institute of Zoology of NAS Ukraine, B. Khmelnitsky Str., 15, 01601, Kiev, Ukraine.
anistrat@ln.ua or anistrat@rambler.ru
ABSTRACT: The protoconch and teleoconch morphology of the Late Badenian and Sarmatian species of the genus Mohrensternia of the
Central Paratethys are described and illustrated. Eight species of the genus are considered valid: Mohrensternia inflata HÖRNES,
1856, M. sarmatica FRIEDBERG, 1923, M. pseudinflata HILBER, 1897, M. perinflata FRIEDBERG, 1923, M. angulata (EICHWALD,
1830), M. pseudangulata HILBER, 1897, M. banatica JEKELIUS, 1944, and ? M. friedbergi sp. nov. A lectotype is designated forRissoa angulata EICHWALD, 1830, the type species of Mohrensternia STOLICZKA, 1868. The type material of all species introduced
by W. FRIEDBERG (1923) is revised and lectotypes are designated for M. sarmatica, M. pseudosarmatica and M. perinflata.
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Late Devonian and early Carboniferous Rugosa from Western Pomerania, northern Poland
CHWIEDUK E.
Institute of Geology, Adam Mickiewicz University, Makow Polnych Str. 16, PL-61-606 Poznan, Poland.
chwieduk@amu.edu.pl
ABSTRACT:The taxonomic description of the Late Devonian and Early Carboniferous Rugosa from the boundary area of the
Precambrian East European Craton and the Palaeozoic platform of Central Europe is presented. Palaeontological analysis
and the stratigraphical distribution of the corals in Western Pomerania enabled recognition of several faunistic events,
which reflect evolutionary trends in rugose corals.
The pre-crisis Frasnian coral fauna, dominated by colonial forms, both massive [Disphyllia laxa (GÜRICH, 1896), Hexagonaria hexagona kowalae WRZOLEK, 1992, ?Frechastraea] and branching [Disphyllum kweihsiense YOH, 1937,Peneckiella ?fascicularis (SOSHKINA, 1952), Thamnophyllum monozonatum (SOSHKINA, 1939), Peneckiella szulczewskii
ROZKOWSKA, 1979], developed on the carbonate platform extending along the edge of the East European Craton. The
similarity of these faunas to Rugosan faunas from southern Poland is significant.
The coral fauna was reduced significantly after the Kellwasser crisis. Colonial corals disappeared altogether and solitary
dissepimented forms were markedly reduced. The subsequent Late Famennian radiation caused a significant quantitative
and qualitative differentiation of the coral faunas. In addition to the well-known ′Cyathaxonia fauna′, warm and
shallow-water solitary corals appeared in the latest Famennian. The stratigraphically important taxa of the latest
Famennian include: Campophyllum MILNE-EDWARDS & HAIM, 1850, ?Palaeosmilia aquisgranense (FRECH, 1885), Bounophyllum pomeranicum sp. nov. and Guerichiphyllum kowalense ROZKOWSKA, 1969.
The latest Famennian regression caused subdivision of the Pomeranian area into at least two sedimentary basins, separated
by shallows, with peculiar ecological conditions, and the appearance of numerous endemic taxa. This regressive
interval contains, however, numerous levels yielding less restricted faunas, which suggest the intermittent appearance of
more open-sea conditions.
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Silica origin and solubility in groundwater from the weathered zone of sedimentary rocks of the Intra-Sudetic Basin, SW Poland
DOBRZYNSKI D.
Institute of Hydrogeology and Engineering Geology, Warsaw University Zwirki i Wigury 93, PL-02-089 Warsaw, Poland
dardob@uw.edu.pl
ABSTRACT:The groundwaters studied in the Intra-Sudetic Basin, SW Poland, occur in the regolith and in the fissured bedrock. Silica concentration in groundwaters ranges from 0.7 to 24.1 mg/L SiO2. Mineral phases that are the source of silica solute were pointed out on bedrock mineralogy and saturation state analysis. Interpretation of aqueous chemistry in terms of mineral stability confirms that partial geochemical equilibrium is maintained. In groundwater with pH values below 4.8 from the fissured aquifer in Carboniferous siliciclastic rocks, kaolinite controls silica solubility. Congruent dissolution of the allophane phase and/or incongruent reaction between the Al(OH)3 form and kaolinite/ halloysite or allophane can be responsible for silica activity in groundwater, with pH values between 5.5 and 6.7, from the regolith on Carboniferous rocks and from the fissured aquifer in Cretaceous mudstones. Groundwaters with pH values above 6.7 occur in the Permian and Cretaceous fissured aquifers which contain calcite/dolomite minerals. Silica and aluminium concentrations in these aquifers are clearly maintained by equilibrium with the hydroxyaluminosilicate HASB. The solubility constant of HASB estimated on groundwater chemistry is lgK HASB = -44.88 (±0.48), which is lower than the recently published experimental value (SCHNEIDER & al. 2004). In groundwater with pH values between 4.8 and 5.5 from the regolith sampled during snow melt, equilibrium, even with reversible secondary aluminosilicates, is not maintained. Silicon and aluminium concentrations result from kinetics or steady-state between weathering release and hydrological removal.
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