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2013
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tom Vol. 57, No. 3
443–-466
EN
The Middle Turonian sediments of the Nysa Kłodzka Graben (Bystrzyca Sandstone in the Stara Bystrzyca outcrop and the Długopole Sandstone in Długopole Górne Quarry) contain trace fossils, which include Curvolithus simplex, ?Macaronichnus isp., Ophiomorpha nodosa, Ophiomorpha isp., Palaeophycus tubularis, Thalassinoides cf. paradoxicus, T. suevicus and Thalassinoides isp. The assemblage of trace fossils points to the proximal Cruziana ichnofacies, that characterizes the distal lower shoreface and the archetypal Cruziana ichnofacies, typical of upper offshore settings. The trace fossils evidence implies that sedimentation took place in a shallow basin with periods of a sudden sediment input, good oxygenation and normal salinity. The Bystrzyca and Długopole sandstones are deposits of the shallow epicontinental sea that were deposited between the fair-weather and storm-wave base, in the distal lower shoreface–upper offshore setting. The Bystrzyca Sandstone is recognized as storm-originated deposits, whereas the Długopole Sandstone is probably the part of prograding “accumulation terrace”. The source of material for the sandstone was the East Sudetic Island and probably also the Orlica–Bystrzyca Uplift. The studied sandstones are related to a regression that started in the early/middle Middle Turonian and caused a relative uplift of the surrounding land.
EN
The following trace fossils have been recognised in the Lower Muschelkalk of Raciborowice Gorne (North Sudetic Synclinorium, SW Poland): Archaeonassa fossulata, Balanoglossites triadicus, ?Gastrochaenolites isp., Lockeia isp., Palaeophycus tubularis, Palaeophycus isp., ?Planolites beverleyensis, P. montanus, Planolites isp., ?Protovirgularia isp., Rhizocorallium commune var. auriforme, R. commune var. irregulare, R. jenense, Skolithos linearis, Thalassinoides suevicus and Trypanites weisei. Coprolites and an unidentified trace fossil A are also described. The trace fossils allow the discrimination of five ichnoassociations in the Raciborowice G1) Rhizocorallium- Pholeus, (IA 2) Rhizocorallium-Palaeophycus, (IA 3) Thalassinoides, (IA 4) Trypanites-Balanoglossites and (IA 5) Planolites-Palaeophycus. The Lower Muschelkalk succession was deposited on a shallow carbonate ramp affected by frequent storms. Deposition commenced with sedimentation in a restricted lagoon on the inner ramp with a short episode of sabkha formation. It continued on the middle and outer ramp and then on a skeletal shoal of the outer ramp and in an open basin. Ichnoassociation IA 5 is related to a maximum transgression that commenced with the deposition of the Spiriferina Bed and which probably marked the opening of the Silesian-Moravian Gate. The basin underwent two shallowing episodes, as evidenced by ichnoassociations IA 3-IA 4, resulting in the formation of hardgrounds. Bathymetric changes in the Raciborowice Gorne section correspond well with a general transgressive trend in the Germanic Basin.
EN
This paper describes and interprets a newly discovered Lower Coniacian (lower Upper Cretaceous) macro- and micro- fossil fauna (vertebrate and invertebrate remains) from sedimentary rocks of the Jerzmanice Zdrój region of the North Sudetic Basin of SW Poland. Several inoceramid bivalve taxa that previously were only known from other parts of the North Sudetic Basin were recovered from light grey, marly sandstones of Early Coniacian age. A fragment of ammonite was also discovered, as was a shark's tooth from the family Cretoxyrhinidae: this may be Cretoxyrhina mantelli Agassiz, 1843, a species not hitherto known from the Lower Coniacian (Emscherian sensu Scupin (1912-13)) of the North Sudetic Basin. Abundant foraminifers were observed in thin sections. The newly discovered inoceramid bivalves - Cremnoceramus deformis erectus Meek, 1877, Cremnoceramus waltersdorfensis waltersdorfensis Andert, 1911 and Inoceramus lusatiae Andert, 1911 - fit into the current biostratigraphic scheme for the region. The inoceramids can all be assigned to the Cremnoceramus deformis erectus Zone, which correlates with the Gavelinella moniliformis foraminiferal Zone and thereby confirms an Early Coniacian age. The Turonian-Coniacian boundary in the North Sudetic Basin can now be placed between the respective inoceramid zones of Inoceramus costellatus Woods, 1912 (actually Mytiloides costellatus Woods, 1912) and Inoceramus schloenbachi Böhm, 1911 (actually Cremnoceramus crassus crassus Petrascheck, 1903). The macrofossils found in the Jerzmanice section suggest that the host sediments were laid down in a Late Cretaceous epicontinental basin, under the North Sudetic Sea, that had deepened during the Early Coniacian. This interpretation agrees with the global bathymetric curve for the Late Cretaceous in Europe.
EN
Many well preserved trace fossils were found in erratic boulders and the fossils preserved in them, occurring in the Pleistocene glacial deposits of the Fore-Sudetic Block (Mokrzeszów Quarry, Świebodzice outcrop). They include burrows (Arachnostega gastrochaenae, Balanoglossites isp., ?Balanoglossites isp., ?Chondrites isp., Diplocraterion isp., Phycodes isp., Planolites isp., ?Rosselia isp., Skolithos linearis, Thalassinoides isp., root traces) and borings ?Gastrochaenolites isp., Maeandropolydora isp., Oichnus isp., Osprioneides kampto, ?Palaeosabella isp., Talpina isp., Teredolites isp., Trypanites weisei, Trypanites isp., ?Trypanites isp., and an unidentified polychaete boring in corals. The boulders, Cambrian to Neogene (Miocene) in age, mainly came from Scandinavia and the Baltic region. The majority of the trace fossils come from the Ordovician Orthoceratite Limestone, which is exposed mainly in southern and central Sweden, western Russia and Estonia, and also in Norway (Oslo Region). The most interesting discovery in these deposits is the occurrence of Arachnostega gastrochaenae in the Ordovician trilobites (?Megistaspis sp. and Asaphus sp.), cephalopods and hyolithids. This is the first report of Arachnostega on a trilobite (?Megistaspis) from Sweden. So far, this ichnotaxon was described on trilobites from Baltoscandia only from the St. Petersburg region (Russia). Arachnostega on a trilobite (Asaphus), a cephalopod and hyolithids is from Russia or Estonia. Another interesting ichnotaxon is Balanoglossites, which also was encountered in the erratic boulders from the Ordovician Orthoceratite Limestone of Sweden. So far, this ichnotaxon was known only from Russia (St. Petersburg region). Some rare borings (e.g., Osprioneides kampto, ?Palaeosabella isp.) also were found in glacial erratics of Silurian stromatoporoids, excellent outcrops of which are located in Gotland (Sweden) and Saaremaa (Estonia). In addition, stromatoporoid/coral, coral/coral and some new fossil associations are reported. The material studied probably was transported from the N, the NE, and less commonly from the NW.
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