Palynostratigraphy of the cretaceous-paleogene mass-extinction interval of the Northern Hemisphere

• For a long time debate has taken place regarding the trends and extinction rates associated with the Cretaceous- Paleogene (K-Pg) mass extinction event on land. While mainly focussed on vertebrates and more especially non-avian dinosaurs, the dynamics of the plant cover remains nonetheless a major component for the understanding the biological response across the K-Pg interval and associated ecosystem destabilization. In this paper, we present a review of the late Cretaceous to Paleogene pollen and spore stratigraphy within the Northern Hemisphere Aquilapollenites paleophytogeographic province. In the United States of America, Late Cretaceous assemblages are marked by the appearance of a series of key-taxa, the Santonian-Campanian transition is characterized by the appearance of Aquilapollenites and associated triprojectate genera, while the base of the Maastrichtian is marked by the appearance of the oculate genus Wodehouseia as well as Kurtzipites sp. The K-Pg extinction event remains easily identifiable in the palynological record with the disappearance of a series of angiospermous taxa part of the Wodehouseia spinata Assemblage Zone, which are characterized by relatively large size and complex wall structure. The recovery palynoflora in the Paleocene is represented by assemblages dominated by porate grains, with key-species from the Momipites and Caryapollenites genera. As current data covers mostly the North American terrestrial record, more research efforts are needed within Chinese,European and Southern Hemisphere localities to provide for a better understanding of the global response of the terrestrialbiosphere to the K-Pg impact event.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geology (hsv//eng)

Nyckelord

spores

pollen

palynology

paleogene

biostratigraphy

cretaceous

mass-extinction

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)