Synthrusting remagnetization of the Krizna nappe: high resolution palaeo- and rock magnetic study in the Strazovce section, Strazovske vrchy Mts, Central West Carpathians (Slovakia)
GRABOWSKI J.1, MICHALIK J.2, SZANIAWSKI R3, GROTEK I.1
1Polish Geological Institute, Rakowiecka 4, 00-975 Warszawa, Poland.
jgra@pgi.gov.pl
2Institute of Geology, Slovak Academy of Sciences, Dubravskaá cesta 9, 842 26 Bratislava, Slovakia
3Institute of Geophysics, Polish Academy of Sciences, Ks. Janusza 64, 01-452 Warszawa, Poland
ABSTRACT: Palaeomagnetic studies of the uppermost Jurassic to lower Cretaceous pelagic carbonates in the Krizna nappe in the
Strážovske vrchy Mts (Central West Carpathians, Slovakia) revealed the presence of secondary magnetite-related magnetization
of exclusively normal polarity (component b), which was most probably acquired during the thrusting episode
in the late Cretaceous. three formations exposed in the Strazovce section were the subject of investigation: Jasenina
(Kimmeridgian–tithonian), osnica (lower–Middle berriasian) and Mraznica (Upper berriasian–hauterivian). Component
b is ubiquitous throughout the section but is strongest in the Mraznica formation. this formation contains a
lot of superparamagnetic particles and shows rock magnetic characteristics typical of chemically remagnetized carbonates.
the remaining two formations, although also remagnetized, bear traces of an older, probably primary magnetization
(component C). the fold test for component b is apparently positive; however the inclination in pre-folding
coordinates is too steep for any expected palaeoinclination of Jurassic to recent age. additional tectonic correction
must be applied to match the palaeoinclinations with expected values. although there is some uncertainty in this additional
correction, all plausible options suggest that the rocks must have been magnetized when they dipped in the
opposite direction to the thrusting direction. this interpretation is concordant with the internal tectonics of the Krizna
nappe, consisting of imbricated units of duplex-type structure.
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New conodont and palynological data from the Lower Palaeozoic in Northern Camdag, NW Anatolia, Turkey
BONCHEVA I.1, GONCUOGLU M.C.2, LESLIE S.A.3, LAKOVA I.1, SACHANSKI V.1, SAYDAM G.2, GEDIK I.4, KONIGSHOF P.5
1Geological Institute, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Bl. 24, 1113 Sofia, Bulgaria.
boncheva2005@yahoo.com
2Middle East Technical University, Department of Geological Engineering, 06531 Ankara, Turkey.
mcgoncu@metu.edu.tr
3Department of Geology and Environmental Science James Madison University, MSC 6903 Harrisonburg, VA 22807 U.S.A.
lesliesa@jmu.edu
4General Directorate of Mineral Research and Exploration, Department of Geological Research, 06520
55Forschungsinstitut und Naturmuseum Senckenberg Senckenberganlage 25 D-60325 Frankfurt am Main – Germany.
Peter.Koenigshof@senckenberg.de
ABSTRACT: Two main thrust slices in the camdag area (NW Anatolia), were informally named the Southern and Northern Camdag
units. New micropaleontological and palynological data about the ordovician, Silurian and devonian in the Northern
Camdag have allowed a better understanding of the early Palaeozoic evolution of this critical area between the
Istanbul Terrane in the west and the Zonguldak Terrane in the east. The Middle ordovician age obtained from the conodont-
bearing limestone band within the Aydos formation in this study is in agreement with the data from the Zonguldag
Terrane. Acritarch evidence suggests a Late ordovician age of the upper part of Aydos formation.
This paper concerns the Northern unit. Three members are distinguished in the findikli formation and dated biostratigraphically.
The lower member (Black Shale Member) of the findikli formation is absent from the kabalak dere
section, but was assigned elsewhere to the Llandovery on the basis of graptolites. The middle member (Shale–Siltstone
Member) is dated as Wenlock and Ludlow on the basis of acritarchs. The upper member (Shale–Limestones Member)
spans a continuous upper Silurian - Lower devonian succession. The overlaying ferizli formation is assigned
to the Middle devonian on the basis of conodonts.
The new stratigraphic data indicate that the Southern Camdag unit corresponds to the Istanbul Terrane and the
Northern Camdag unit to the Zonguldak Terrane. The tectonic contact between the Northern and the Southern units
is a steep south-verging thrust-fault.
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Famennian chondrichthyan remains from the Chahriseh section, central Iran
HAIRAPETIAN V.1, GINTER M.2
1Department of Geology, Islamic Azad University, Khorasgan branch, PO Box 81595-158, Esfahan, Iran.
vachik@khuisf.ac.ir
2Institute of Geology, University of Warsaw, Zwirki i Wigury 93, 02-089 Warsaw, Poland.
m.ginter@uw.edu.pl
ABSTRACT: a diverse shallow water assemblage of chondrichthyan microremains is described from the Famennian of the
Chahriseh section, central Iran. twenty-two taxa are identified; of these two new taxa viz. Roongodus phijani gen.
et sp. nov. (hybodontoidea) and Arduodens flammeus gen. et sp. nov. (Ctenacanthiformes) have been erected. two
morphoecological subtypes of Ph. gothicus dentition, characteristic of deeper and shallower shelves, are proposed.
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Trace fossils from the Lower–Middle Jurassic Bardas Blancas Formation, Neuquen Basin, Mendoza Province, Argentina
BRESSAN G.S.1, PALMA R.M.1,2
1Departamento de Ciencias Geologicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon II, Buenos Aires C1428 EHA, Argentina.
gbressan@gl.fcen.uba.ar
2Consejo Nacional de Investigaciones Científicas y Tecnicas (CONICET), Argentina.
palma@gl.fcen.uba.ar
ABSTRACT: Trace fossil associations from the Lower–Middle Jurassic siliciclastic succession of the northern Neuquen Basin,
Argentina are described and their palaeoenvironmental interpretation is discussed. The Bardas Blancas Formation
displays facies of lower foreshore to offshore environments, such as massive and laminated mudstones, laminated
siltstones, hummocky cross-stratified sandstones, massive and laminated sandstones, wave-rippled sandstones,
as well as fine- to medium-grained bioclastic sandstones and massive conglomerates. They contain a trace
fossil assemblage low in abundance but high in diversity. The assemblage, comprising eleven ichnogenera, is
dominated by Skolithos, Chondrites, Thalassinoides, Planolites, Palaeophycus, Taenidium, Gyrochorte and Arenicolites.
Gordia, ?Diplocraterion and Lockeia are less abundant. These trace fossils belong to the Skolithos,
Cruziana and Zoophycos ichnofacies. Their distribution is controlled mainly by hydrodynamic energy, substrate
consistency and oxygen levels. Storm beds exhibit two successive stages of colonization: (1) the pioneer stage,
during which Skolithos, Diplocraterion and Arenicolites (elements of the Skolithos ichnofacies), were produced;
and (2) the stable environment stage, represented by Chondrites, Thalassinoides, Taenidium, Gyrochorte, Gordia,
Lockeia, Palaeophycus and Planolites (elements of the Cruziana ichnofacies). deeper environments exhibit
a low diversity association with Chondrites and Thalassinoides, characterizing the Zoophycos ichnofacies.
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Small theropod and ornithopod footprints in the Late Jurassic of Poland
GIERLINSKI G.D.1,3, NIEDZWIEDZKI G.2, NOWACKI P.3
1Polish Geological Institute, ul. Rakowiecka 4, 00-975 Warszawa, Poland.
gierlinski@yahoo.com
2Institute of Zoology, Faculty of Biology, University of Warsaw, ul. S. Banacha 2, 02-097 Warszawa, Poland
2Jura Park, ul. Sandomierska 4, 27-400 Ostrowiec Swietokrzyski, Poland
ABSTRACT: Late Jurassic material of small theropod and ornithopod dinosaur footprints are reported from the northeastern
slope of the Holy cross Mountains, Poland. the ichnites occur in five lithostratigraphical units of an epicontinental
basin in central Poland. Small theropod tracks, Wildeichnus isp. and Jialingpus isp., came from the baltow
Platy Limestones, baltow coral Limestones and wierzbica oolite and Platy Limestones. Four specimens of small
ornithopod footprints, assigned to Dinehichnus isp., were found in the blaziny oolite Limestones and wierzbica
oolite and Platy Limestones. a medium-sized ornithopod footprint, identified as cf. Dinehichnus isp., was discovered
in the ozarow oolite and Platy Limestones. the described footprints from the Upper Jurassic of Poland
are smaller than similar types of ichnites from other parts of the world. the Polish Late Jurassic dinosaur community
probably represented a diminutive insular fauna.
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A new occurrence of sharks in the Menilite Formation (Lower Oligocene) from the Outer (Flysch) Carpathians of Poland
BIENKOWSKA-WASILUK M.1,2, RADWANSKI A.1
1Institute of Geology, University of Warsaw, Al. Zwirki i Wigury 93, PL-02-089 Warszawa, Poland.
2Institute of Paleobiology, Polish Academy of Sciences, Twarda 51/55, PL-00-818 Warszawa, Poland.
mbienk@twarda.pan.pl
ABSTRACT: Two newly recognized sections (Jamna Dolna 2 and Wola Czudecka) of the Lower Oligocene Menilite shales
(Menilite Formation) in the Polish Outer (Flysch) Carpathians have recently yielded a small shark assemblage.
it comprises teeth of Heptranchias howelli (reed, 1946), not hitherto reported from europe, as well as the remains
of other sharks (teeth of ?Mitsukurina, Alopias, gillrakers of Cetorhinus) all contributing to the fish assemblage
of the Carpathian Menilite Formation, which has long been famous mostly for its teleost content. the
life environment of the studied sharks and the basin bottom conditions are briefly discussed.
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Miocene lacustrine succession of the Hoyran Lake Basin, Isparta, southwest Turkey
TOPAK Y.1, GUL M.2, YAMAN S.1
1Cukurova University, Engineering and Architecture Faculty, Department of Geological Engineering, Balcali, 01330, Adana, Turkey.
ytopak@mail.cu.edu.tr
2Mugla University, Engineering Faculty, Department of Geological Engineering, Kotekli, 48000, Mugla, Turkey
ABSTRACT: The Hoyran Lake Basin is an example of a Neogene rift basin in southwest Turkey. Initially red coloured, poorlysorted,
angular cobble to pebble conglomerates were deposited close to the boundary faults. These conglomerates
then passed into the finer-grained, calcite-cemented pebble to granule conglomerates towards the basin interior.
The distributions of other lacustrine lithofacies (siltstone/claystone, marlstone, limestone and magnesite)
appear to have been dependent on the proximity of the lake margins. These occurrences show that the basin was
subject to some climatic and tectonic controls. Humid seasons and/or tectonic activities resulted in increased clastic
input from the lake margins, drier conditions enhanced evaporation and significantly modified the water chemistry.
Ultramafic and dolomitic older rocks around the basin are considered to have been an important source for
the ion concentrations implicated in the precipitation of dolomite and magnesite in the Hoyran Lake deposits.
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A new rissoid gastropod with lecithotrophic development from the Miocene of Paratethys
ANISTRATENKO V.
I.I. Schmalhausen Institute of Zoology of NAS Ukraine, B. Khmelnitsky Str., 15, 01601 Kiev, Ukraine.
Institute of Geological Sciences of Polish Academy of Sciences, Geological Museum, Senacka Str., 1, 32-002,
Krakow, Poland.
anistrat@izan.kiev.ua
ABSTRACT: The results of detailed morphological studies on Rissoa sobieskii from the Badenian of the eastern Central
Paratethys are presented. its paucispiral protoconch with a bulbous embryonic shell indicates it to have had a
lecithotrophic (non-planktotrophic) larval development, apparently lacking even a short free-swimming larval
stage. this contrasts with all other known Miocene Rissoa species, which have shell features indicating a
planktotrophic larval stage. the peculiarity of R. sobieskii is also supported by its characteristic narrowing of
the aperture and almost complete lack of teleoconch sculpture. the time coincidence of the appearance of the
non-planktotrophic species with distinct changes in salinity of the badenian basin suggests that the alteration
("switching") of the type of early ontogeny from planktotrophic to non-planktotrophic development could have
been an environmentally induced phenomenon.
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Palygorskite in Miocene rocks of northern Iraq: environmental and geochemical indicators
AL-JUBOURY A. I.
Research Center for Dams and Water Resources, Mosul University, Iraq.
alialjubory@yahoo.com
ABSTRACT: The mineralogical characteristics of palygorskite from the Lower Miocene Euphrates Formation and the Middle
Miocene Fat’ha (Lower Fars) succession in north and northwestern Iraq were studied by X-ray diffraction (XRD), Infrared
spectroscopy (IR) and scanning electron microscopy (SEM) with EDAX analysis. Palygorskite is the common
clay mineral in the rocks studied, together with small amounts of illite, chlorite, and kaolinite, in addition to various
amounts of quartz, feldspar, dolomite and calcite. It is believed that most of the clay minerals are detrital in origin, except
palygorskite, which is formed by authigenesis in evaporitic environments. Marl beds of the Euphrates Formation
were deposited in a lagoonal, relatively saline environment, suitable for the neoformation of palygorskite. the
Fat’ha Formation is composed mainly of an evaporitic sequence. It consists of numerous shallowing-upward cycles
of alternating mudrock, limestone, gypsum and/or anhydrite and halite in the basin centre. this depositional environment
favours the authigenic formation of palygorskite and partly its diagenetic formation by transformation of precursor
clays, mainly smectite and mixed-layer illite-smectite, as revealed by scanning electron microphotographs.
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