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Ammonites and magnetostratigraphy of the Berriasian–Valanginian boundary deposits from eastern Crimea

References Aguado R., Company M. & Tavera J.M. 2000: The Berriasian-Valanginian boundary in the Mediterranean region: new data from the Caravaca and Cehegı´n sections, SE Spain. Cretaceous Res. 21, 1-21. Arkadiev V.V. 2015: New occurrences of the genus Riasanites (Ammonoidea) in the Upper Berriasian of the Eastern Crimea. Contributions to current cephalopod research: Morphology, Systematics, Evolution, Ecology and Biostratigraphy. In: Leonova T.B., Barskov I.S. & V.V. Mitta (Eds.):Proceedings of conference (Moscow, 2-4 April

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Microbiostratigraphy of the Berriasian–Valanginian boundary in eastern Crimea: foraminifers, ostracods, organic-walled dinoflagellate cysts

.A. & Shurekova O.V. 2016: Berriasian-Valanginian boundary in the Crimean Mountains. In: Michalík J & Fekete K. (Eds.): XIIth Jurassica Conference. IGCP 632 and ICS Berriasian workshop. April 19-23, 2016, Smolenice, Slovakia. Field Trip Guide and Abstracts Book. Earth Science Institute, Slovak Academy of Sciences, Bratislava, 79-82. Arkadiev V.V., Grishchenko V.A., Guzhikov A.Yu., Manikin A.G., Savelieva Y.N., Feodorova A.A. & Shurekova O.V. 2017: Ammonites and magnetostratigraphy of the Berriasian-Valanginian boundary deposits from eastern Crimea. Geol. Carpath

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Biostratigraphy and paleoecology of the Lower Cretaceous sediments in the Outer Western Carpathians (Silesian Unit, Czech Republic)

-159. Hanzlíková E. & Roth Z. 1963: Review of the Cretaceous stratigraphy of the Flysch Zone in the West Carpathians. Geol. Sbor. SAV 14, 1, 37-81. Holbourn A.E.L. & Kaminski M.A. 1995: Valanginian to Barremian benthic Foraminifera from ODP Site 766 (Leg 123, Indian Ocean). Micropaleontology 41, 3, 197-250. Homola V. & Hanzlíková E. 1955: Biostratigraphical, tectonic and lithological studies in the Těšín area. Sbor. Ústř. Úst. Geol. 21/1954, P, 317-502 (in Czech). Houša V. 1975: Geology and

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An Upper Jurassic-Lower Cretaceous carbonate platform from the Vâlcan Mountains (Southern Carpathians, Romania): paleoenvironmental interpretation

Phanerozoic. In: Farinacci A. & Lord A. R. (Eds.): Depositional episodes and bioevents. Palaeopelagos, Spec. Publ. 2, 53-104. Bucur I. I. & Săsăran E. 2005: Relationship between algae and environment: an Early Cretaceous case study, Trascău Mountains, Romania. Facies 51, 274-286. Bucur I. I., Conrad M. A. & Radoičić R. 1995: Foraminifers and calcareous algae from the Valanginian limestones in the Jerma River Canyon, Eastern Serbia. Rev. Paléobiologie 14, 2, 349-377. Burgess P. M. 2006: The

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Erosion of a Jurassic ophiolitic nappe-stack as indicated by exotic components in the Lower Cretaceous Rossfeld Formation of the Northern Calcareous Alps (Austria)

Abstract

The microfacies and biostratigraphy of components in mass-flow deposits from the Lower Cretaceous Rossfeld Formation of the Northern Calcareous Alps in Austria were analysed. The pebbles are classified into six groups: 1) Triassic carbonates (uppermost Werfen to basal Gutenstein Formations), 2) Upper Jurassic to lowermost Cretaceous carbonates (Oberalm Formation and Barmstein Limestone), 3) contemporaneous carbonate bioclasts (?Valanginian to ?Hauterivian), 4) siliceous pebbles (radiolarites, ophicalcites, siliceous deep-sea clays, cherts), 5) volcanic and ophiolitic rock fragments and 6) siliciclastics such as quartz-sandstones and siltstones. The radiolarites show three age groups: Ladinian to Early Carnian, Late Carnian/Norian and Late Bajocian to Callovian. The Middle Triassic radiolarites are interpreted as derived from the Meliata facies zone or from the Neotethys ocean floor, whereas the Late Triassic radiolarites give evidence of the sedimentary cover of the Neotethys ocean floor. During late Early to early Late Jurassic, the Triassic to Early/Middle Jurassic passive margin of the Neotethys attained a lower plate position and became obducted by the accreted ocean floor of the Neotethys Ocean. The accreted ocean floor was contemporaneously eroded and resedimented in different deep-water basins in front of the nappe-stack. These basin fills were subsequently incorporated in the orogen forming mélanges in this complex ophiolitic nappe-stack. The Middle Jurassic radiolarites are interpreted as the matrix of these mélanges. Together with the volcanic and ophiolitic material the siliceous rocks were eroded from this ophiolitic nappe-stack in Early Cretaceous times and brought by a fluvial system to the Rossfeld Basin within the Tirolic realm of the Northern Calcareous Alps. The different fining-upward sequences in the succession of the Lower Cretaceous Rossfeld Formation can be best explained by sea-level fluctuations and decreasing tectonic activity in the Jurassic orogen

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Jurassic–Cretaceous radiolarian-bearing strata from the Gresten Klippen Zone and the St. Veit Klippen Zone (Wienerwald, Eastern Alps, Austria): Implications for stratigraphy and paleogeography

Abstract

Two sections of the klippen zones in the Wienerwald area have been investigated for their stratigraphy: (1) The Gern section of the Main Klippen Zone, a part of the Gresten Klippen Zone, and (2) the St. Veit Klippen Zone in the Lainz Tunnel and the neighboring outcrops in western Vienna. New biostratigraphic data are based on radiolaria from siliceous intervals and a few findings of calcareous nannofossils from marlstones. In the Gresten Klippen Zone, radiolarian assemblages from limestones of the Gern locality indicate a middle Oxfordian to early Kimmeridgian age of the Scheibbsbach Formation.

Radiolarian and nannofossil data from the St. Veit Klippen Zone in the Lainz railway tunnel locality, as well as correlated outcrops from the Lainzer Tiergarten and the Gemeindeberg in the southwest of Vienna, indicate the presence of mainly Bajocian to lower Oxfordian red radiolarites and cherts (Rotenberg Formation). Siliceous, grey limestones and cherts of the Fasselgraben Formation range from the upper Oxfordian–Kimmeridgian to the Valanginian–Barremian.

The Main Klippen Zone was derived from the European margin to the north, and this zone is regarded as a Helvetic paleogeographic unit. The St. Veit Klippen Zone in the Lainz Tunnel section contains no ophiolitic material and shows a tectonic contact with the surrounding Rhenodanubian nappe system, which indicates no primary sedimentary contact of the St. Veit Klippen Zone with the Flysch units, as well as demonstrating the presence of two structurally separated Alpine tectonic units. Thus, a direct correlation with the Ybbsitz Zone is not supported, and an original paleogeographic position in the transition from the Penninic Ocean to the Austroalpine continental fragment is proposed.

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Comment on “Calpionellid distribution and microfacies across the Jurassic/Cretaceous boundary in western Cuba (Sierra de los Órganos)” by López-Martínez et al. (2013)

-696. Myczyński R. & Pszczółkowski A. 1990: Tithonian stratigraphy in the Sierra de los Organos, Western Cuba: correlation of the ammonite and microfossil zones. In: Fossili, Evoluzione, Ambiente (Atti del secondo convegno internazionale, Pergola 25-30 ottobre 1987), Edit. Comitato Cent. Raffaele Piccinini, 405-415. Pop G. 1976: Tithonian-Valanginian calpionellid zones from Cuba. D.S. ed., Inst. Geol. Geofiz (3. Paleont.) 62, 237-266. Pop G. 1986: Calpionellids and correlation of Tithonian-Valanginian formations. Acta Geol. Hung

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Reply to the Comment of A. Pszczółkowski on “Calpionellid distribution and microfacies across the Jurassic/Cretaceous boundary in western Cuba (Sierra de los Órganos)” by López-Martínez et al. (2013)

: Fossili, Evoluzione, Ambiente (Atti del secondo convegno internazionale, Pergola 25-30 ottobre 1987). Edit. Comitato Cent. Raffaele Piccinini, 405-415. Pop G. 1976: Tithonian-Valanginian calpionellid zones from Cuba. D.S. ed., Inst. Geol. Geofiz. (3. Paleont.) 62, 237-266. Pszczółkowski A. 1978: Geosynclinal sequences of the Cordillera de Guaniguanico in western Cuba; their lithostratigraphy, facies development, and paleogeography. Acta Geol. Pol. 28, 1, 1-96. Pszczółkowski A. 1999: The exposed passive margin of North

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The fossil record of tadpoles

Abstract

Anurans are characterized by a biphasic lifecyle, consisting of radically different larval (“tadpole”) and adult (“frog”) morphs. Although the fossil record for tadpoles is more limited compared to the record for frogs, it is more extensive and informative than generally appreciated. The tadpole fossil record consists exclusively of body fossils, often in the form of skeletons with associated soft tissues. Tadpole fossils are known from more than 40 localities of Early Cretaceous (late Berriasian – early Valanginian) to late Miocene age: 24 localities (Early Cretaceous and Cenozoic) in Europe, mostly from deposits of middle Eocene – Miocene age in central and southern Germany and northern Czech Republic; four or five localities (Miocene) in Asia; five localities (latest Cretaceous – Miocene) in continental Africa; and three localities each on the Arabian Plate (Early Cretaceous and Oligocene) and in North America (Eocene) and South America (Campanian and Paleogene). Fossil tadpoles are assignable to at least 16 species belonging to 13 genera and five (possibly as many as seven) families. The tadpole fossil record is dominated by pipoids (Pipidae, Palaeobatrachidae, Rhinophrynidae, and basal pipimorphs), but also includes representatives of Pelobatidae and Ranidae, and possibly Pelodytidae and ?Discoglossidae sensu lato. The tadpole fossil record is limited to lacustrine deposits, yet a significant number of localities in those deposits have yielded size series of tadpole body fossils that have proven informative for examining ontogenetic patterns. Other body fossils suggested at various times to be tadpoles are reviewed: the enigmatic Middle Devonian Palaeospondylus is a fish; the unique holotype specimen of the basal Triassic proto-frog Triadobatrachus is a fully transformed individual, not a metamorphic tadpole; a fossil from the Middle or Late Jurassic of China originally described as a tadpole is an insect; a small skeleton from the Early Cretaceous of Israel originally reported as a tadpole likely is not; and the identity of a fossil preserved within a piece of Miocene Dominican amber and said to be a tadpole hatching from an egg cannot be verified. Extant tadpoles are known to excavate shallow depressions (so-called tadpole nests or holes) in fine-grained sediments at the bottom of shallow, low energy water bodies; however, there is no convincing evidence for those structures or any other traces attributable to the activities of tadpoles in the fossil record.

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Stratigraphy, plankton communities, and magnetic proxies at the Jurassic/Cretaceous boundary in the Pieniny Klippen Belt (Western Carpathians, Slovakia)

References Andreini G., Caracuel J.E. & Parisi G. 2007: Calpionellid biostratigraphy of the Upper Tithonian–Upper Valanginian interval in Western Sicily (Italy). Swiss J. Geosci. 100, 179–198. Andreini G. Caracuel J.E. Parisi G. 2007 Calpionellid biostratigraphy of the Upper Tithonian–Upper Valanginian interval in Western Sicily (Italy) Swiss J. Geosci. 100 179 198 Anderson T.F. & Arthur M.A. 1983: Stable isotope of oxygen and carbon and their application to sedimentologic and environmental problem. In: Arthur M

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