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1
Content available Quantitative data on the genus Loftusia from the Zagros Mts., northern Iraq
Görmüş M., Nuaimy Q. A. M., Ameen Lawa F. A.
Acta Geologica Polonica
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2018
|
Vol. 68, no. 2
207--218
EN
The Maastrichtian sediments of northern Iraq are rich in larger benthic foraminifera. Among them, the genus Loftusia is well-known one because of its significant palaeogeographic distribution across the Mediterranean and Middle East. In this study, observations of abnormal test shapes, species recognition criteria and endoskeleton characteristics of Loftusia are discussed, based on the new material from north-eastern Iraq. The following species of Loftusia are described: Loftusia elongata Cox, L. persica Brady, Loftusia morgani Douvillé, L. anatolica Meriç, L. matsumarui Meriç and Görmüs, L. minor B Cox, L. ketini B Meriç and L. kahtaensis Meriç, Loftusia minor A Cox, L. oktayi Meriç and L. baykali Meriç. The predominant species are Loftusia elongata, L. morgani and L. baykali. Skewed abnormal individuals and epidermal parts of the endoskeleton structure are also interesting aspects to note. Quantitative data obtained for Loftusia allow us to better understand and interpret species identification criteria, abnormal occurrences and the endoskeleton structure.
2
Content available remote Paleomagnetic results from Northeast Anatolia: remagnetization in Late Cretaceous sandstones and tectonic rotation at the Eastern extension of the Izmir–Ankara–Erzincan suture zone
Çinku M. C.
Acta Geophysica
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2017
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Vol. 65, no. 6
1095--1109
EN
Paleomagnetic results obtained from Upper Cretaceous sandstones in Northeastern Anatolia demonstrate that the entire area from Erzincan to Kars has been remagnetised. The remagnetisation was acquired before the Middle Eocene collision between the Eastern Pontides and the Arabian Platform because Middle Eocene sandstones carry primary natural remanent magnetisations. The post-folding in situ mean direction of the Upper Cretaceous sandstones is compared with mean directions of younger, Middle Eocene to present rock formations. As a result, a twostage antagonistic rotation mechanism is proposed. First, the collision between the Pontides and the Taurides between Late Cretaceous and Middle Eocene was associated by clockwise rotation of ~ 26°. In the second stage between Middle Eocene and Middle Miocene and beyond, counterclockwise rotations up to ~ 52° of the Pontide and Anatolide blocks and clockwise rotations of the Van Block were characterised by regional shortening and westward escape.
3
Content available A new homolid crab, Zygastrocarcinus tricki sp. nov., from the Pierre Shale (middle Campanian), Baculite Mesa, Pueblo County, Colorado, USA
Nyborg T., Bedell M., Garassino A., Larson N. L., Bishop G. A.
Acta Geologica Polonica
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2016
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Vol. 66, no. 4
709--713
EN
A new species of homolid crab, Zygastrocarcinus tricki sp. nov., is reported from the Late Cretaceous (middle Campanian, Baculites scotti Zone) of the Pierre Shale Formation (Baculite Mesa, Pueblo County, Colorado). This nearly complete homolid, hereto described is the sixth species assigned to the genus and extends our knowledge along with the geographical range and geological age of this taxon.
4
Content available Litostratygrafia i charakterystyka mikropaleontologiczna utworów kredy dolnej w środkowej części przedgórza Karpat
Urbaniec A., Bobrek L., Świetlik B.
Przegląd Geologiczny
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2010
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Vol. 58, nr 12
1161-1175
EN
During the Early Cretaceous a central part of the Carpathian Foreland was situated in the Peri-Tethys area. That zone was located on the SW margin of the East European Craton and it was adjacent to the Tethys basins in the south. Impact of those both zoogeographic provinces (the Boreal Sea and the Tethys Ocean) is easily noticeable in assemblages of microfauna. Character of sedimentation in the Early Cretaceous basin of the Carpathian Foreland is connected mainly with changes of the sea-level as well as tectonic activity of this region. The stratigraphy and facies data are based on near two hundreds wells profiles. Detailed sedimentological profiles and photographic documentation of the Upper Jurassic and the Lower Cretaceous deposits from about 50 boreholes were done as well as micropalaeontological and microfacial studies of core samples. The presented work is an attempt of unification and formalization of lithostratigraphic units’ nomenclature. Two boreholes: Zagorzyce-7 andWiewiórka-4 were suggested as stratotype sections of distinguished formations. Jurassic–Cretaceous boundary is probably situated within limits of Ropczyce formation in this area. Three formations have been distinguished in the profile of Lower Cretaceous above Ropczyce formation: Zagorzyce limestone-marl formation (Berriasian age), Dębica marl and organodetritic limestone formation (Valanginian) andWiewiórka limestone formation (Late Valanginian-Hauterivian). The most marked erosion surface is recorded between Zagorzyce and Dębica formations. We suppose that hiatus including a large part of Lower Valanginian profile is connected with that erosion surface. It could be refered to a rapid fall of the sea-level in the Tethys Ocean, noticed inter alia in theWestern Carpathians and the Northern Calcareous Alps. The known existing thickness of the Lower Cretaceous sediments in the middle part of Carpathian Foreland (total of three formations: Zagorzyce fm., Dębica fm. andWiewiórka fm.) rises to 188 m in Zagorzyce-1 well.
5
Content available Biostratygrafia mikropaleontologiczna utworów kredy górnej i miocenu w wierceniu "Bibice" (okolice Krakowa)
Zapałowicz-Bilan B., Pilarz M., Machaniec E.
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
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2009
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T. 35, z. 2/1
95-103
EN
Lower Campanian marls and marly opokas with cherts ("Bibice" borehole, Kraków vicinity) are rich in benthic forams (mainly Stensioeina and Gavelinella species) and rare planktic ones (Hedbergella). The overlying Miocene deposits (Kłodnik and Skawina beds), are developed as conglomerates (equivalent of fresh-water marls in Krakow region) which are completely devoid of microfossils, but younger clays are full of the Badenian forams.
6
Content available remote The Eastern Sudetic Island in the Early-to-Middle Turonian : evidence from heavy minerals in the Jerzmanice sandstones, SW Poland
Biernacka J., Józefiak M.
Acta Geologica Polonica
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2009
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Vol. 59, no. 4
545-565
EN
The Eastern Sudetic Island was an emerged area in the late Cretaceous shelf-sea of central Europe that delivered coarse siliciclastic material to adjacent basins. The extent of this land area during the Early-to-Middle Turonian has been reconstructed on the basis of a heavy-mineral analysis of the Jerzmanice sandstones from the North Sudetic Basin. The heavy minerals studied predominantly derive from medium to high grade metamorphic rocks, such as granulites and metabasites, calc-silicate rocks, mica schists and gneisses, and from garnet peridotites and pegmatites/granites. The interpretation of various heavy mineral species provides evidence that the major part of the detritus constituting the Jerzmanice sandstones was supplied from a relatively small area of the fore-Sudetic part of the Gory Sowie Massif and its immediate vicinity, approx. 50 km away from the depositional site. Heavy minerals and particularly the chemical characteristics of detrital garnets, Cr-spinels and tourmalines, have turned out to be excellent indicators of the provenance of these mature late cretaceous sandstones.
7
Content available remote Paleoekologia i paleośrodowisko późnego kampanu na podstawie wybranych profili z doliny środkowej Wisły
Zatoń M.
Przegląd Geologiczny
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2003
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Vol. 51, nr 8
678-684
PL
Trzy odsłonięcia górnego kampanu, należące do trzech kolejnych poziomów amonitowych (Neancyloceras phaleratum, Bostrychoceras polyplocum i Didymoceras donezianum) w dolinie środkowej Wisły, zostały zbadane pod kątem paleośrodowiskowym. Bogata makrofauna ze wszystkich szczebli troficznych, świadczy o spokojnym środowisku, odpowiadającemu dzisiejszej strefie pogranicza wewnętrznego i zewnętrznego szelfu, o normalnym zasoleniu, dobrze natlenionych wodach przydennych i podłożu o zróżnicowanej konsystencji, stwarzającego różnorodnej faunie odmienne nisze ekologiczne.
EN
The paleoecology of macrofauna from three Upper Campanian outcrops in the Middle Vistula valley, belonging to three successive ammonite zones (Neancyloceras phaleratum, Bostrychoceras polyplocum and Didymoceras donezianum), have been investigated on paleoenvironmental ground. The rich macrofauna of all trophic levels indicates the calm epicratonic basin, corresponding to the inner to outer shelf environment, of normal salinity waters, good bottom-water oxygenation and with substrate of varied consistency, providing different niches for diverse fauna.
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