ABSTRACT As the major weather divide in Europe, the Alps represent one of the most interesting ar... more ABSTRACT As the major weather divide in Europe, the Alps represent one of the most interesting areas for understanding past climate change and its impact on continental environments. However, our knowledge of the Quaternary environmental history of the region is still rather limited, especially for the time preceding the last glaciation of the Alps. The sedimentary filling of overdeepened troughs - elongated depressions of subglacial origin cut into both unconsolidated sediments and bedrock - are excellent archives for various environmental reconstructions. Here, we present the results of a study of the glacially overdeepened Wehntal trough, northwest of Zurich, mainly based on multi-proxy data and luminescence chronology of a 93.6 m long sediment core, which has been drilled down to Miocene bedrock in the village of Niederweningen. This core represents one of the very few records in the northern Alpine Foreland that provides crucial insights into timing of erosion and infilling history of pre-Eemian glacially overdeepened structures. The recovered succession is interpreted from bottom to top as: in-situ molasse bedrock, overlain by diamictic till during Marine Isotope Stage (MIS) 8. It is suggested that this extensive ice advance caused the final erosion of the bedrock. The till merges seamlessly into laminated, carbonate-rich, fine-grained siliciclastic proglacial lake sediments, which accumulated also during MIS 8. This unit was deposited proximal to a calving glacier-front as confirmed by the presence of numerous dropstones. The overlaying lake sediments are comparable to the former unit, but the absence of dropstones indicates a more distal lake facies and thus, a retreat of the glacier lobe during MIS 7. Low organic carbon contents point to almost no biological activity and suggest cold environmental conditions. The continuous succession is now interrupted by a hiatus that covers almost the complete MIS 6, which is believed to represent a major glaciation of the Alps. Although a striking drop in carbonate content and shear strength, as well as an increase in grain size can be noticed in the topping sequence, no obvious erosional features are visible in the sediment fabric. The top of the unconformably overlying unit documents a gradual infilling of the palaeolake and onset of biological productivity due to climate warming during early MIS 5. The prominent environmental change culminates in the abrupt accumulation of peat during late MIS 5e. During early MIS 3, the peat was flooded, producing silty sediments, which show relative high organic carbon contents. Thereafter, the palaeolake was filled again, resulting in the accumulation of fossil-rich peat c. 45 ka ago, which was finally covered with local alluvial silts and sands.
Figure 9. A, Ternary diagram showing the range of body proportions in selected Saurichthys specie... more Figure 9. A, Ternary diagram showing the range of body proportions in selected Saurichthys species. 1, S. rieppeli sp. nov., 2, S. grignae, 3, S. longimedialis, 4, S. longipectoralis, 5, S. minuta, 6, S. costasquamosus, 7, S. paucitrichus, 8, S. breviabdominalis sp. nov., 9, S. macrocephalus, 10, S. curionii, 11, S. deperditus, 12, S. striolatus, 13, S. brevirostris. B, Phylomorphospace showing the negative relationship between opercular depth and axial elongation in saurichthyid fishes.
The Alpine Prosanto Formation (Middle Triassic) cropping out in the Ducan region in eastern Switz... more The Alpine Prosanto Formation (Middle Triassic) cropping out in the Ducan region in eastern Switzerland has yielded a rich fish and reptile fauna. Here, we present new pachypleurosaur remains from the upper part of the formation (Early Ladinian), similar to the previously known pachypleurosaurs from the Middle Triassic UNESCO World Heritage Site of Monte San Giorgio in southern Switzerland/northern Italy. From these remains, a new pachypleurosaur species, Prosantosaurus scheffoldi nov. gen. et spec., is described on the basis of six fairly complete skeletons, one disarticulated specimen and an isolated skull. As is typical for pachypleurosaurs and most other Triassic marine reptiles, the new taxon is based to a large degree on a combination of characters (e.g., nasals articulating broadly with the anterior margins of the prefrontals and lacking posterior processes; postorbitals with rounded anterior processes that articulate with the postfrontals anterolaterally) rather than on many...
Figure 4. Saurichthys rieppeli sp. nov. fins (PIMUZ T 61, holotype). A, Dorsal fin. B, Anal fin. ... more Figure 4. Saurichthys rieppeli sp. nov. fins (PIMUZ T 61, holotype). A, Dorsal fin. B, Anal fin. C, Magnified view of dorsal fin baseosts (middle radials), with annuli visible on the distal ends of the anterior two elements. D, Pelvic fins. E, Caudal fin; inset shows a close-up of the distally bifurcating lepidotrichia and the fringing fulcra (indicated by arrows) along the leading edge of the hypochordal lobe. Abbreviations: scu, scutes. Scale bar = 10 mm.
Johannes Miocic1, Ruth Drescher-Schneider2, Hans Rudolf Graf3, Marlu Kühn4, Frank Preusser1, Wern... more Johannes Miocic1, Ruth Drescher-Schneider2, Hans Rudolf Graf3, Marlu Kühn4, Frank Preusser1, Werner H. Schoch5, Nigel Thew6, Lucia Wick4, and Heinz Furrer7 1Institute of Earth and Environmental Sciences, Albert-Ludwigs-Universität Freiburg, Albertstr. 23b, 79104 Freiburg, Germany, 2Schilingsdorfer Straße 27, 8010 Kainbach bei Graz, Austria, 3Dr. von Moos AG, Bachofnerstrasse 5, 8037 Zürich, Switzerland,4Integrative Prähistorische und Naturwissenschaftliche Archäologie, Universität Basel, 4055 Basel, Switzerland, 5Labor für Quartaere Hoelzer/ Laboratory for Ancient Wood Research, Unterrütistrasse 17, 8135 Langnau a.A., Switzerland, 6Rue Paul Bouvier 2, 2000 Neuchâtel, Switzerland, 7Paläontologisches Institut und Museum Universität Zürich, 8006 Zürich, Switzerland
Foreyia maxkuhni gen. et sp. nov. 1 Department of Geology and Palaeontology, Muséum d'Histoir... more Foreyia maxkuhni gen. et sp. nov. 1 Department of Geology and Palaeontology, Muséum d'Histoire Naturelle, CP6434, 1211, Geneva, 6, Switzerland. 2 Naturhistorisches Museum Basel,Augustinergasse 2, 4001, Basel, Switzerland. 3 Erliackerweg 8, 4462, Rickenbach, BL, Switzerland. 4 Paläontologisches Institut und Museum der Universität Zürich, Karl Schmid-Strasse 4, 8006, Zurich, Switzerland.Correspondence and requests for materials should be addressed to L.C. (email: lionel.cavin@ ville-ge.ch) Etymology The generic name honors late Peter L. Forey for his contribution on the study of coelacanth fishes. The specific epithet refers to Max Kuhn, who kindly supported for 12 years the preparation and study of fossils from the Middle Triassic of Graubünden and especially the specimens described here. Holotype A complete specimen preserved in left lateral view (PIMUZ A / I 4620) (Figs 1, 2 C, S 2, S 4, S 6). Paratype A specimen comprising the head and the tail in left lateral view (PIMUZ A/I ...
ABSTRACT As the major weather divide in Europe, the Alps represent one of the most interesting ar... more ABSTRACT As the major weather divide in Europe, the Alps represent one of the most interesting areas for understanding past climate change and its impact on continental environments. However, our knowledge of the Quaternary environmental history of the region is still rather limited, especially for the time preceding the last glaciation of the Alps. The sedimentary filling of overdeepened troughs - elongated depressions of subglacial origin cut into both unconsolidated sediments and bedrock - are excellent archives for various environmental reconstructions. Here, we present the results of a study of the glacially overdeepened Wehntal trough, northwest of Zurich, mainly based on multi-proxy data and luminescence chronology of a 93.6 m long sediment core, which has been drilled down to Miocene bedrock in the village of Niederweningen. This core represents one of the very few records in the northern Alpine Foreland that provides crucial insights into timing of erosion and infilling history of pre-Eemian glacially overdeepened structures. The recovered succession is interpreted from bottom to top as: in-situ molasse bedrock, overlain by diamictic till during Marine Isotope Stage (MIS) 8. It is suggested that this extensive ice advance caused the final erosion of the bedrock. The till merges seamlessly into laminated, carbonate-rich, fine-grained siliciclastic proglacial lake sediments, which accumulated also during MIS 8. This unit was deposited proximal to a calving glacier-front as confirmed by the presence of numerous dropstones. The overlaying lake sediments are comparable to the former unit, but the absence of dropstones indicates a more distal lake facies and thus, a retreat of the glacier lobe during MIS 7. Low organic carbon contents point to almost no biological activity and suggest cold environmental conditions. The continuous succession is now interrupted by a hiatus that covers almost the complete MIS 6, which is believed to represent a major glaciation of the Alps. Although a striking drop in carbonate content and shear strength, as well as an increase in grain size can be noticed in the topping sequence, no obvious erosional features are visible in the sediment fabric. The top of the unconformably overlying unit documents a gradual infilling of the palaeolake and onset of biological productivity due to climate warming during early MIS 5. The prominent environmental change culminates in the abrupt accumulation of peat during late MIS 5e. During early MIS 3, the peat was flooded, producing silty sediments, which show relative high organic carbon contents. Thereafter, the palaeolake was filled again, resulting in the accumulation of fossil-rich peat c. 45 ka ago, which was finally covered with local alluvial silts and sands.
Figure 9. A, Ternary diagram showing the range of body proportions in selected Saurichthys specie... more Figure 9. A, Ternary diagram showing the range of body proportions in selected Saurichthys species. 1, S. rieppeli sp. nov., 2, S. grignae, 3, S. longimedialis, 4, S. longipectoralis, 5, S. minuta, 6, S. costasquamosus, 7, S. paucitrichus, 8, S. breviabdominalis sp. nov., 9, S. macrocephalus, 10, S. curionii, 11, S. deperditus, 12, S. striolatus, 13, S. brevirostris. B, Phylomorphospace showing the negative relationship between opercular depth and axial elongation in saurichthyid fishes.
The Alpine Prosanto Formation (Middle Triassic) cropping out in the Ducan region in eastern Switz... more The Alpine Prosanto Formation (Middle Triassic) cropping out in the Ducan region in eastern Switzerland has yielded a rich fish and reptile fauna. Here, we present new pachypleurosaur remains from the upper part of the formation (Early Ladinian), similar to the previously known pachypleurosaurs from the Middle Triassic UNESCO World Heritage Site of Monte San Giorgio in southern Switzerland/northern Italy. From these remains, a new pachypleurosaur species, Prosantosaurus scheffoldi nov. gen. et spec., is described on the basis of six fairly complete skeletons, one disarticulated specimen and an isolated skull. As is typical for pachypleurosaurs and most other Triassic marine reptiles, the new taxon is based to a large degree on a combination of characters (e.g., nasals articulating broadly with the anterior margins of the prefrontals and lacking posterior processes; postorbitals with rounded anterior processes that articulate with the postfrontals anterolaterally) rather than on many...
Figure 4. Saurichthys rieppeli sp. nov. fins (PIMUZ T 61, holotype). A, Dorsal fin. B, Anal fin. ... more Figure 4. Saurichthys rieppeli sp. nov. fins (PIMUZ T 61, holotype). A, Dorsal fin. B, Anal fin. C, Magnified view of dorsal fin baseosts (middle radials), with annuli visible on the distal ends of the anterior two elements. D, Pelvic fins. E, Caudal fin; inset shows a close-up of the distally bifurcating lepidotrichia and the fringing fulcra (indicated by arrows) along the leading edge of the hypochordal lobe. Abbreviations: scu, scutes. Scale bar = 10 mm.
Johannes Miocic1, Ruth Drescher-Schneider2, Hans Rudolf Graf3, Marlu Kühn4, Frank Preusser1, Wern... more Johannes Miocic1, Ruth Drescher-Schneider2, Hans Rudolf Graf3, Marlu Kühn4, Frank Preusser1, Werner H. Schoch5, Nigel Thew6, Lucia Wick4, and Heinz Furrer7 1Institute of Earth and Environmental Sciences, Albert-Ludwigs-Universität Freiburg, Albertstr. 23b, 79104 Freiburg, Germany, 2Schilingsdorfer Straße 27, 8010 Kainbach bei Graz, Austria, 3Dr. von Moos AG, Bachofnerstrasse 5, 8037 Zürich, Switzerland,4Integrative Prähistorische und Naturwissenschaftliche Archäologie, Universität Basel, 4055 Basel, Switzerland, 5Labor für Quartaere Hoelzer/ Laboratory for Ancient Wood Research, Unterrütistrasse 17, 8135 Langnau a.A., Switzerland, 6Rue Paul Bouvier 2, 2000 Neuchâtel, Switzerland, 7Paläontologisches Institut und Museum Universität Zürich, 8006 Zürich, Switzerland
Foreyia maxkuhni gen. et sp. nov. 1 Department of Geology and Palaeontology, Muséum d'Histoir... more Foreyia maxkuhni gen. et sp. nov. 1 Department of Geology and Palaeontology, Muséum d'Histoire Naturelle, CP6434, 1211, Geneva, 6, Switzerland. 2 Naturhistorisches Museum Basel,Augustinergasse 2, 4001, Basel, Switzerland. 3 Erliackerweg 8, 4462, Rickenbach, BL, Switzerland. 4 Paläontologisches Institut und Museum der Universität Zürich, Karl Schmid-Strasse 4, 8006, Zurich, Switzerland.Correspondence and requests for materials should be addressed to L.C. (email: lionel.cavin@ ville-ge.ch) Etymology The generic name honors late Peter L. Forey for his contribution on the study of coelacanth fishes. The specific epithet refers to Max Kuhn, who kindly supported for 12 years the preparation and study of fossils from the Middle Triassic of Graubünden and especially the specimens described here. Holotype A complete specimen preserved in left lateral view (PIMUZ A / I 4620) (Figs 1, 2 C, S 2, S 4, S 6). Paratype A specimen comprising the head and the tail in left lateral view (PIMUZ A/I ...
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