pISSN 0705-3797 eISSN 2586-1298
HOME Article View

Article

Episodes 2013; 36(3): 162-198

Published online September 1, 2013

https://doi.org/10.18814/epiiugs/2013/v36i3/001

Copyright © International Union of Geological Sciences.

The Global Stratotype Sections and Point (GSSP) for the base of the Jurassic System at Kuhjoch (Karwendel Mountains, Northern Calcareous Alps, Tyrol, Austria)

Hillebrandt, A.v.1, Krystyn, L.2, Kürschner, W.M.3, Bonis, N.R.4, Ruhl, M.5, Richoz, S.6, Schobben, M. A. N.12, Urlichs, M.7, Bown, P.R.8, Kment, K.9, McRoberts, C.A.10, Simms, M.11, and Tomãsových, A13

1Institut für Angewandte Geowissenschaften, Technische Universität, Ernst-Reuter-Platz 1, 10587 Berlin, Germany. E-mail: axel.vonhillebrandt@campus.tu-berlin.de
2Department for Palaeontology, Vienna University, Geozentrum, Althansstr. 9, A-1090 Vienna, Austria. E-mail: leopold.krystyn@univie.ac.at
3Department of Geosciences and Centre of Earth Evolution and Dynamics (CEED), University of Oslo, PO box 1047, Blindern, 0316 Oslo, Norway. E-mail: w.m.kuerschner@geo.uio.no
4Shell Global Solutions International B.V., Kessler Park 1, 2288 GS, Rijswijk, the Netherlands. E-mail: nina.bonis@shell.com
5Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3AN, UK. E-mail: micha.ruhl@earth.ox.ac.uk
6Commission for the Palaeontological and Stratigraphical Research of Austria, Austrian Academy of Sciences c/o Institut of Earth Sciences, Graz University, Heinrichstraße 26, 8010 Graz, Austria. E-mail: sylvain.richoz@uni-graz.at
7Staatliches Museum für Naturkunde, Rosenstein 1, 70191 Stuttgart, Germany. E-mail: max.urlichs@smns-bw.de
8Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, UK. E-mail: p.bown@ucl.ac.uk
9Lenggrieser Str. 52, 83646 Bad Tölz, Germany. E-mail: kurt.kment@moralt-tischlerplatten.de
10Department of Geology, State University of New York at Cortland, P.O. Box 2000, Cortland, New York 13045, USA. E-mail: mcroberts@cortland.edu
11Ulster Museum, Botanic Gardens, Belfast BT9 5AB, UK. E-mail: michael.simms@magni.org.uk
12Museum für Naturkunde, Berlin, Invalidenstrasse 43, 10115 Berlin, Germany. E-mail: martin.schobben@mfn-berlin.de
13Geological Institute Slovak Academy of Science, Dubravska cesta 9, Bratislava, 84005, Slovakia. E-mail: geoltoma@savba.sk

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The Global Stratotype Section and Point (GSSP) defining the base of the Jurassic System Lower Jurassic Epoch and Hettangian Stage is situated at the Kuhjoch pass, Karwendel Mountains, Northern Calcareous Alps, Austria (47°29′02″N/11°31′50″E). The Triassic-Jurassic (T-J) boundary is exposed at Kuhjoch West and at Kuhjoch East, and corresponds to the first occurrence (FO) of the ammonite Psiloceras spelae tirolicum. The “Golden Spike” was fixed at Kuhjoch East. The section displays a high and continuous sedimentation rate with a constant facies trend across the boundary level. Other bio-events include the FO of the aragonitic foraminifer Praegubkinella turgescens, and of diverse ostracod species 1.0-3.40 cm below the FO of P. spelae and 3.2 m below P. spelae occurs the continental palynomorph Cerebropollenites thiergartii. Because of the lack of other terrestrial microfloral events this is yet the FO event closest to the FO of P. spelae and allows a correlation with nonmarine sediments. The δ13Corg record shows a strong initial negative excursion at the boundary between the Kössen and Kendlbach formations, 5.8 m (Kuhjoch W) below the T-J boundary, a shift to more positive δ13Corg in the Schattwald Beds and a gradual decline to more negative values at the transition of the Schattwald Beds to the proximate Tiefengraben Mb. The stratotype point lies within a zone of smaller negative and positive δ13Corg peaks, which is superimposed on a longer lasting main negative shift. According to recent investigations, the radiometric age of the T-J boundary is about 201,3 Ma.