Geologos, 2010, 16, 3

Permanent URI for this collection


Recent Submissions

Now showing 1 - 4 of 4
  • Item
    Source and depositional processes of coarse-grained limestone event beds in Frasnian slope deposits (Kostomłoty-Mogiłki quarry, Holy Cross Mountains, Poland)
    (Bogucki Wydawnictwo Naukowe, 2010-10) Vierek, Aleksandra
    The Kostomłoty-Mogiłki succession is situated in the Kostomłoty transitional zone between the shallow-water Kielce stromatoporoid-coral platform and the deeper Łysogóry basin. In the Kostomłoty-Mogiłki quarry, the upper part of the Szydłówek Beds and Kostomłoty Beds are exposed. The Middle-Upper Frasnian Kostomłoty Beds are composed of shales, micritic and nodular limestones with abundant intercalations of detrital limestones. The dark shales and the micritic and nodular limestones record background sedimentation. The interbedded laminated and detrital limestones reflect high-energy deposition (= event beds). These event beds comprise laminated calcisiltites, fine-grained calcarenites, coarse-grained grain-supported calcirudites fabrics, and matrix-supported calcirudites. The material of these event beds was supplied by both erosion of the carbonate-platform margin and cannibalistic erosion of penecontemporaneous detrital limestones building the slope of this platform. Storms and the tectonic activity were likely the main causes of erosion. Combined and gravity flows were the transporting mechanisms involved in the reworking and redeposition.
  • Item
    Bryozoans from the Jurginskaya Formation (Famennian, Upper Devonian) of the Tom-Kolyvansk area (Western Siberia, Russia)
    (Bogucki Wydawnictwo Naukowe, 2010-10) Tolokonnikova, Zoya
    Nine bryozoan species are described from the Jurginskaya Formation (Famennian, Late Devonian) from Western Siberia, Russia, namely: Leptotrypella pojarkovi Orlovski, 1961, Rhombopora subtilis Nekhoroshev, 1977, Klaucena lalolamina Yang, Hu, Xia, 1988, Eofistulotrypa famennensis sp. n., Atactotoechus cellatus sp. n., Nikiforopora jurgensis sp. n., Eridotrypella tyzhnovi sp. n., Mediapora elegans sp. n., and Klaucena gracilis sp. n. The studied assemblage shows palaeogeographical affinity with Kazakhstan, Kirgizia, Transcaucasia, China, and the United States of America.
  • Item
    The usefulness of a taphonomic approach for studies of Pleistocene mammals
    (Bogucki Wydawnictwo Naukowe, 2010-10) Pawłowska, Kamilla
    The potential usefulness of taphonomical research for studies of Pleistocene mammal remains is detailed. The required taphonomical research involves two stages. The first one is the biostratinomical stage, which concerns the time between the death of the organism and its burial; for this time-span, the spatial distribution of the remnants is analysed, as well as the weathering marks, the activity of predators (i.e. gnawing and digestion), the influence of temperature, intentional human activity, rodent marks (i.e. gnawing), and trampling. in the second one is the diagenetic stage, which deals with the time-span from the burial of the remnants to their discovery; for this time-span, the influence of physical and chemical processes (including diagenetic alterations of the deposit, the influence of water, and plant-root marks) are considered. The application of taphonomical analysis provides the possibility of reconstructing the environmental conditions under which the skeleton or bone complex was preserved, as well as the depositional history of the bones (postconsumption remnants, flood remains, accumulation of bones by predators). This opens new possibilities for the study of Pleistocene bones in Poland.
  • Item
    Stratigraphic evidence of a Late Maeotian (Late Miocene) punctuated transgression in the Tanais Palaeobay (northern part of the Eastern Paratethys, South-West Russia)
    (Bogucki Wydawnictwo Naukowe, 2010-10) Ruban, Dymitry A.
    The Tanais Palaeobay was located in the northern periphery of the eastern Paratethys Sea during the Late Miocene. New data from the Safianovo section (Rostov Dome, South-West of Russia) confirm that skeletal limestones (coquinites) of the Merzhanovskaja Formation belong to the Congeria (Andrusoviconcha) amygdaloides navicula Zone of the upper Upper Maeotian (the Maeotian is a regional chronostratigraphic unit of the Upper Miocene). Correlation of reference sections of these Upper Maeotian deposits within the Rostov Dome results in pattern of the palaeobay transgression, which was punctuated. The relative importance of local and global controls on this trangsression is not yet clear.
Uniwersytet im. Adama Mickiewicza w Poznaniu
Biblioteka Uniwersytetu im. Adama Mickiewicza w Poznaniu
Ministerstwo Nauki i Szkolnictwa Wyższego