Aretz et al_2011.pdf - ORBi - Université de Liège

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Kölner Forum Geol. Paläont., 19 (2011)
M. ARETZ, S. DELCULÉE, J. DENAYER & E. POTY (Eds.)
Abstracts, 11th Symposium on Fossil Cnidaria and Sponges, Liège, August 19-29, 2011
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synsedimentary extensional tectonics, increased weathering and siliciclastic supply. Various types of
bioconstructions were developed preferentially during the late TST and the early HST of the third-order
sequences. During Aptian shallow-water Urgonian sedimentation was reduced. As many carbonate
platforms on the northern margin of Tethys (see HELDT et al. 2010) during the Early–Middle Aptian
platforms in Bulgaria were progressively drowned, and carbonate sedimentation disappeared (MINKOVSKA
et al. 2002).
These studies were supported by a research grant from the Polish Ministry of Science and Higher
Education (No. 2P04D 028 29).
HELDT, M., LEHMANN, J., BACHMANN, M., NEGRA, H. & KUSS, J. (2010): Increased terrigenous influx but no drowning:
palaeoenvironmental evolution of the Tunisian carbonate platform margin during the Late Aptian. -
Sedimentology, 57: 695–719.
IDAKIEVA, V. (2003): Lower Cretaceous Scleractinia in a part of Central Fore-Balkan (taxonomy and buildups). PhD
Thesis, Sofia University, 327 pp. (in Bulgarian)
IDAKIEVA, V. & IVANOV, M. (2002): Coral buildups in the Smochan Formation (Urgonian, Lower Cretaceous) around
Lovech (Central North Bulgaria). – Annales de l’Université de Sofia “St. Kl. Ohridski”, Faculté de Géologie et
Géographie, 95: 31-46. (in Bulgarian)
KOŁODZIEJ, B., IDAKIEVA, V. & IVANOV, M. (2011): Unique Early Cretaceous development of phaceloid pachythecaliines
(Scleractinia?, Hexanthiniaria?): Upper Barremian, Bulgaria. - This volume.
MINKOVSKA, V., PEYBERNÈS, B., NIKOLOV, T. & IVANOV, M. (2002): Paleogeographic reconstruction of a segment of the
North-Tethyan margin in Bulgaria from Barremian to Albian. - Eclogae geologica Helvetica, 95: 183–195.
SANDERS, D. & BARON-SZABO, R.C. (2005): Scleractinian assemblages under sediment input: their characteristics and
relation to the nutrient input concept. - Palaeogeography, Palaeoclimatology, Palaeoecology, 216: 139–181.
ZLATARSKI, V. (1967): Dimorphocoeniopsis beauvaisorum, une nouvelle espèce de Madreporaria du Crétacé inférieur de la
Bulgarie du Nord. – Doklady Bolgarskoj Akademii Nauk, 20: 1317–1320.
Fig. 1 (next page): A. Upper part of the Lovech Urgonian Group showing intercalations of carbonate and siliciclastic
formations. B, C. Marls with abundant branching (phaceloid, ramose) corals preserved in growth position. Coral
debris visible on C is due to recent weathering. Lovech –Goznica (Upper Barremian). D. Lower part of a platy
colony preferentially encrusted by heterotrophic organisms: serpulids, ostreids, thecideid brachiopods, bryozoans
and sponges. E. Example of clausastreid corals which attain the largest colony size, possibly representing the most
sediment resistent taxa. F. Massive, thamnasteriod coral colony, subject a few sedimentation/tilting events. G–I.
Dimorphocoeniopsis beauvaisorum ZLATARSKI. On G conical pedestal morphotype. J. Lower surface of Actinoseris?
alloiteaui BEAUVAIS & ZLATARSKI. Orbitolinid test often provided a suitable substrate for settling of larvae of this
species. K. Floria planinensis TURNŠEK & MIHAJLOVIĆ from carbonates. L. Clear-water coral bioconstruction.
Numerous borings, encrustation by microbialites and heterotrophic organims and lack of Lithocodium encrustation
suggest higher nutrient level. M. Large skeleton of pachythecaliine coral.
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