Microfossils in resin from the middle Eocene Buchanan Lake Formation, Napartulik, Axel Heiberg Island, Nunavut, Canada

Autor(en)

Hans Halbwachs, Fridgeir Grimsson, Marina Potapova, Martina Dolezych, Ben LePage

Abstrakt

During the warm middle Eocene (ca 45 Ma), the Napartulik area (also called ‘the Geodetic Hills’), Axel Heiberg Island, northern Canada (Nunavut), was vegetated with mixed broad-leaved deciduous angiosperm and evergreen conifer forests over extensive floodplain and forested wetland habitats. Massive organic rich sedimentary successions and encapsulated in-situ tree trunks suggest these forests were drowned by frequent flooding events. The sedimentary layers contain sub-fossil amber that was produced by representatives of the Pinaceae such as Pseudolarix. The amber offered an opportunity to investigate aerial plankton and thus the chance to discover microfossils, which could provide evidence of biotic interactions associated with, or the cause of, the forest die-offs. Fifty-four amber samples were subjected to a solvent treatment for microfossil extraction followed by light microscopy, resulting in the discovery of several hundred microfossils. Unexpectedly, one-quarter of the microfossils were diatoms, which may predominantly have lived on the tree bark. Fungal spores were rare, and the pollen grains found corroborated earlier findings in litter or coal. The records of fungal spores and arthropod remains were insignificant and could, therefore, not substantially have been contributing to the forest die-offs. More resin analyses from the complete sedimentary profile would be needed to get a clearer picture of putative forest pests and prevailing environmental conditions

Organisation(en)

Department für Botanik und Biodiversitätsforschung

Externe Organisation(en)

Johann Wolfgang Goethe-Universität Frankfurt am Main, Drexel University, Senckenberg Naturhistorische Sammlungen Dresden, National Taiwan University

Journal

Palynology

Band

47

Seiten

1-13

Anzahl der Seiten

13

ISSN

0191-6122

DOI

https://doi.org/10.1080/01916122.2022.2127956

Publikationsdatum

2023

Peer-reviewed

Ja

ÖFOS 2012

105117 Paläobotanik, 106008 Botanik, 106015 Geobotanik

Schlagwörter

ASJC Scopus Sachgebiete

Palaeontology

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/1d9fc4a8-0d28-4d96-8134-7745380941dc