
Åsa Wallin
Forskningsingenjör

The Ordovician Tøyen Shale (Floian) and its graptolite fauna at Kinnekulle, Västergötland, Sweden–a regional overview
Författare
Summary, in English
The graptolites of the Tøyen Shale Formation of Kinnekulle in Västergötland, south-central Sweden, are described for the first time and their biostratigraphic distribution is documented from drill core and outcrop material. The faunas indicate an age of mid to late Floian (Billingenian), thus showing a reduced biostratigraphic range of the Tøyen Shale as compared to other areas where this rock unit occurs. A considerable stratigraphic gap is apparent at its base, from the late Tremadocian to mid-Floian, as the limestones of the Ceratopyge acicularis trilobite Zone (late Tremadocian Bjørkåsholmen Formation) are followed by shales with a fauna of the Baltograptus jacksoni graptolite Biozone. Unverified records suggest that mid–late Ottenbyan (Hunnebergian) strata (Megistaspis planilimbata trilobite Zone s.l.) locally may be present in the uppermost Bjørkåsholmen Formation as identified herein. There is no indication that the Tøyen Shale reaches into the Dapingian, as Dapingian graptolites have not been recognized. The overlying limestones of the “Lanna Limestone” belong to the Megistaspis polyphemus trilobite Zone and the Baltoniodus triangularis conodont Zone, suggesting a gradual contact of the lithological units.
Avdelning/ar
- Berggrundsgeologi
- Kvartärgeologi
Publiceringsår
2023
Språk
Engelska
Sidor
97-112
Publikation/Tidskrift/Serie
GFF
Volym
145
Issue
3-4
Dokumenttyp
Artikel i tidskrift
Förlag
Taylor & Francis
Ämne
- Geology
Nyckelord
- biostratigraphy
- graptolites
- Kinnekulle
- Kinnekulle-1 drillcore
- Ordovician
- Sweden
- Västergötland
Aktiv
Published
ISBN/ISSN/Övrigt
- ISSN: 1103-5897