Late Paleozoic geodynamics of the Malopolska Massif in the light of new paleomagnetic data for the southern Holy Cross Mountains
SZANIAWSKI R.
Institute of Geophysics of the Polish Academy of Sciences, Ks. Janusza 64, PL-01-452 Warsaw, Poland.
rafsz@igf.edu.pl
ABSTRACT: Paleomagnetic studies of Devonian carbonate rocks in the southernHoly CrossMountains have been conducted, the
general aim being to verify the occurrence of hypothetical pre-Variscan rotations of the Malopolska Massif as well
as to examine time-relationships between remagnetizations and successive stages in tectonic deformations. The paleomagnetic
analysis confirms the presence of the three components of characteristic remnant magnetization. Two
magnetite-bearing components display reversed (componentA) and normal (component B) polarity. The third component
(C) is recorded on hematite and shows reversed polarity. Component B is of synfolding origin and has been
recorded during theVisean, whereas components A and C are of postfolding origin and represent Early Permian and
Permo-Triassic overprints. These results confirmthe stable position of the Malopolska Massif with respect to the East
European craton, at least since the Visean. Results of fold tests imply that the earliest phases of Variscan deformation
can be datedmost probably as Visean, while formation of the main Variscan fold structures was completed during
the Early Permian. It is also documented that representative Variscan folds did not significantly change their
geometry duringMaastrichtian-Paleocene reactivation.
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Pleistocene neotectonics and Fe-mineralizations in the Ahnet-Mouydir area (northern margin of the Hoggar Massif, Algerian Sahara)
WENDT J., NEUMANN U., SCHULZ H.
Institut fur Geowissenschaften der Universitat, Sigwartstrasse 10, D 72076 Tubingen, Germany.
jobst.wendt@uni-tuebingen.de
udo.neumann@uni-tuebingen.de
hartmut.schulz@uni-tuebingen.de
ABSTRACT: Strongly mineralized lithologies were found in 4 different depositional settings along the northern margin of the
Hoggar Massif in southern Algeria: (1) Pleistocene fluvial terraces, (2) pebble-filled erosional furrows in marine
Silurian and Upper Devonian shales, (3) sedimentary dykes in Givetian mud buildups and (4) tectonic faultfissures
and cracks in Upper Devonian shales. In spite of the contrasting sedimentary environment, all these
rocks display very similar properties and are considered as contemporaneous. They are characterized by high
porosities, intense Fe-mineralization and a great variety of accompanying, secondary minerals formed in a subrecent
continental regime under pluvial to arid conditions. The dykes, faults and cracks are direct evidence of
tensional stress during the early and middle Pleistocene which has not been observed so far. The complex sedimentary
and diagenetic history of conglomerates, breccias, sandstones, ferricretes, calcretes and claystones in
these settings was analyzed using SEM, EDX-microprobe, XRD, transmitted and reflected light petrography and
is documented in hitherto unknown details.
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Ferroan dolomite cement in Cambrian sandstones: burial history and hydrocarbon generation of the Baltic sedimentary basin
SLIAUPA S.1,2, CYZIENE J.3 , MOLENAAR N.4, MUSTEIKYTE D.3
1Institute of Geology and Geography Lithuania, Department of Regional Geology, T. Sevcenkos 13, LT-2600 Vilnius, Lithuania.
sliaupa@geo.lt
2Vilnius University, Department of Geology and Mineralogy, M.K.Ciurlionio 21/27, LT-03101 Vilnius, Lithuania.
3Lithuanian Geological Survey, S.Konarskio 35, LT-03123 Vilnius, Lithuania.
jolanta.ciziene@lgt.lt
4Institute of Environment & Resources, Technical University of Denmark, Bygningstorvet, Building 115, DK-2800 Kgs. Lyngby, Denmark.
nim@er.dtu.dk
ABSTRACT: The conditions and timing of carbonate cementation in Cambrian sandstones of the Baltic sedimentary basin were
determined by oxygen and carbon stable isotope and chemical data in combination with optical and cathodoluminescence
petrographic studies. Studied samples represent a range in present burial depth from 340 to 2150 m. The
carbonate cement is dominantly ferroan dolomite that occurs as dispersed patches of poikilotopic crystals. Temperatures
of dolomite precipitation, based on δ18O values, range from 27°C in the shallow buried to 95°C in the deep
buried sandstones. The burial historymodelling points to development ofmost of the dolomite cement during rapid
Silurian-Devonian subsidence and Carboniferous-early Permian uplift.Awide range of precipitation temperatures
indicate that temperature was not a major factor in triggering the carbonate cementation. Dolomite precipitation is
related to early stages of organic matter maturation and thus to the oil generation history in the basin. δ13C values
vary from +0.03‰ to -6.2‰ (PDB), suggesting limited addition of carbon from an organic source, with the major
part derived from marine bicarbonate. The sourcing of carbon from the organic-rich Cambrian shales is identified
from the distribution of δ13C values in the dolomite cement within the Cambrian section. The chemical composition
of the dolomite cement shows a depth-controlled trend that is coincident with the present-day hydrochemical
zonation of the Cambrian aquifer. The increase in the Fe content of the dolomite towards the deeper buried part of
the Baltic basin is related to increasing sourcing of ions (Fe and Mg) from adjacent shales.
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Lithostratigraphy and regional significance of the Nowa Slupia Group (Upper Silurian) of the Lysogory Region (Holy Cross Mountains, Central Poland)
KOZLOWSKI W.
Institute of Geology, University of Warsaw, Zwirki i Wigury Str., 93, PL-02-089 Warszawa, Poland.
woko@uw.edu.pl
ABSTRACT: The Ludlovian-Lochkovian succession of the Lysogory Region of the Holy Cross Mountains (Central Poland) represents
an infill of a Caledonian foreland basin situated at the SWmargin of the East European Craton (EEC). The
facies pattern and transport directions indicate that the source area was located westward fromthe basin and was separated
from the Baltica mainland by the epicratonic sea. The 2.5 km thick succession, defined here as the Nowa Slupia
Group, has been subdivided into 9 formations (from bottom to top: Trzcianka, Trochowiny, Winnica / Rachtanka,
Sarnia Zwola / Bronkowice, Podchelmie, Rudki and Bostow formations). Arevised lithostratigraphic scheme has been
constructed. The lower part of the Nowa Slupia Group (Trzcianka and Trochowiny formations) represents the underfilled
stage of the basin development and is composed of flysch-like sediments. The upper part of the group represents
the filled to overfilled stage of the basin. In the latter stage the lateral migration of two main facies: red
continental deposits (represented by the Rachtanka and Podchelmie formations) and open shelf hemipelagic sediments
(represented by the Sarnia Zwola and Rudki formations and referred here to the Podlasie facies), is observed.
The lateral faciesmigrations probably resulted fromeustatic fluctuations. The twomain facies zones are separated by
a narrowbelt of neritic sediments (represented by theWinnica, Bronkowice andBostow formations),which are known
for their rich benthic fauna. The facies trends observed show that during the latest Ludlovian through early Pridolian,
the boundary between the continental and marine facies in the Lysogory Region was oriented parallel to the Baltica
margin (NNW-SSE).
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Trace fossil Artichnus pholeoides igen. nov. isp. nov. in Eocene turbidites, Polish Carpathians: possible ascription to holothurians
ZHANG G.1, UCHMAN A.2, CHODYN R.2, BROMLEY R. G.3
11Department of Resources and Environmental Engineering, Henan Polytechnic University, 454100, Jiaozuo City, Henan Province, PR China
zhanggc@hpu.edu.cn
2Institute of Geological Sciences, Jagiellonian University, Poland
alfred.uchman@uj.edu.pl
rafal.chodyn@uj.edu.pl
3Geological Museum, Oster Voldgade 5-7, DK-1350 Copenhagen K, Denmark
rullard@geol.ku.dk
ABSTRACT: A hitherto unknown trace fossil was found in some abundance in turbidites of the Polish Outer Carpathians.
The occurrence is within the Hieroglyphic Beds of the Silesian Nappe, within the Szczyrzyc Synclinorium, of
Middle Eocene age. The trace fossil is a wide, J-shaped structure having a narrow, upward tapering shaft as a
connection to the seafloor. The distal end also tapers, to a blind termination. The burrow lumen is surrounded
by an irregular spreite structure. The trace fossil is compared with the work of burrowing holothurians, which
show some comparative features that suggest a tracemaker belonging to the Apodida.
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Eco-taphonomy of mass-aggregated giant balanids Concavus (Concavus) concavus (DARWIN, 1854) from the Lower Pliocene (Zanclean) of Rafina near Pikermi (Attica, Greece)
RADWANSKA U., RADWANSKI A.
Institute of Geology, University of Warsaw, Zwirki i Wigury, 93, PL-02-089 Warszawa, Poland.
u.radwanska@uw.edu.pl
ABSTRACT: The large- to giant-sized balanids, mass-aggregated in a tempestite of the Lower Pliocene (Zanclean) section at Rafina
near Pikermi,Greece, represent a single species, Concavus (Concavus) concavus (DARWIN, 1854) [non BRONN,
1831], the taxonomy of which is revised. The peculiarly shaped forms ‘raphanoides‘ and ‘scutorum‘ are ecophenotypes
of this species; the same applies to the ‘tulipiformis‘ specimens reported previously fromthis section.Discussed
are dynamic events controlling the life and death conditions in the nearshore (offshore) environment of Rafina,
where the giant specimens of Concavus (Concavus) concavus (DARWIN, 1854) flourished through several successive
generations.As opportunistic species they adopted the r-selection reproduction strategy in order to dominate over
other biota. The intermittent action of high-energy agents was responsible for the production of balanid-shell hash
that involved taphonomic feedback. This enabled further colonization of the biotope and the growth of multiphased
(bouquet-like and pyramidal) clusters. The demise of the monospecific balanid communities is ascribed to a heavy
storm which stirred-up the whole balanid-bearing sequence, to produce a proximal tempestite. This final burial and
subsequent depositional lull in the Rafina environment was favoured by a temporary deepening of the whole Lower
Pliocene (Zanclean) basin beyond the bathymetric range in which the balanid population could survive.
Shell colour pattern in two fossil helicid snails, Tropidomphalus incrassatus (KLEIN, 1853) and Cepaea sylvestrina gottschicki WENZ, 1919, from the Middle Miocene of Poland
GORKA M.
Institute of Geology, University of Warsaw, Zwirki i Wigury Str., 93 PL-02-089 Warszawa, Poland.
magurka@uw.edu.pl
ABSTRACT: Two fossil helicid snails, Tropidomphalus incrassatus (KLEIN, 1853) and Cepaea sylvestrina gottschicki WENZ,
1919, from the "detrital Sarmatian" (Middle Miocene) of the northernmost part of the Fore-Carpathian Depression
were macroscopically analysed in daylight and UV-light to reveal the original shell colour pattern. The analysis
shows a high degree of polymorphism in C. sylvestrina gottschicki, similar to that in the extant species Cepaea
nemoralis (LINNAEUS, 1758) and Cepaea hortensis (O.F. MÜLLER, 1774), and results in the recognition of eight
different banding patterns, at least four of which have never been presented before. The banding type in T. incrassatus
shows strong convergence with that in the extant representatives of the Campylaeinae. It is suggested
that restoration of the original shell colour pattern may serve as a useful tool in palaeoecological reconstructions.
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