Late Triassic (early Carnian) palynology of shallow stratigraphical core 7830/5-U-1, offshore Kong Karls Land, Norwegian Arctic
2017
Paterson, Niall William | Mangerud, Gunn | Mørk, Atle
Palynostratigraphical and palynofacies data are presented from a shallow stratigraphical core (7830/5-U-1) drilled in the northern Barents Sea, offshore Kong Karls Land, Arctic Norway. The core spans approximately 127 m of the Snadd Formation (De Geerdalen Formation equivalent). Samples from core 7830/5-U-1 yielded a well-preserved and taxonomically diverse palynomorph association indicative of an earliest Late Triassic (Carnian) age, consistent with previously published Rhenium-Osmium (Re-Os) dates from other cores drilled in the area. The rare occurrence of angiosperm-like pollen confirms previous observations in the Triassic of the Barents Sea area. Palynofacies evidence and the occurrence of marine microplankton and macrofossils indicate that deposition occurred in an offshore marine environment which became increasingly proximal during latter stages of deposition. Variations in the relative abundance of terrestrial organic matter, rhythmic pulses in amorphous organic matter (AOM) content, and the occurrence of acritarchs and prasinophycean algae suggest episodic fluctuations along a nearshore-offshore trend. Palynomorph ecogroup (PEG) analysis reveals a dominance of spore and pollen types characteristic of coastal plain habitats. Sporadic peaks in hinterland pollen types, recorded in association with AOM, are interpreted to reflect the ‘Neves Effect’. The relatively high abundance of fern, sphenopsid and lycopsid spores is considered indicative of a humid climatic regime. A new informal palynozone termed the Podosporites cf. amicus assemblage is described, contributing to a more detailed regional palynological zonation for the Carnian of the Barents Sea region.
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