Cretaceous and Cenozoic dinoflagellate cysts and other palynomorphs from the western and eastern margins of the Labrador–Baffin Seaway

Abstract

New palynological analysis of samples from 13 offshore wells on the Canadian Margin and six wells on the West Greenland Margin has led to a new event biostratigraphic framework for Cretaceous–Cenozoic strata of the Labrador Sea – Davis Strait – Baffin Bay (Labrador–Baffin Seaway) region. This framework is based on about 150 dinoflagellate cyst taxa and 30 acritarch, algal, fungal and plant microfossil (mostly miospore) taxa. In the systematics we include three new genera of dinocysts (Scalenodinium, Simplicidinium and Taurodinium), 16 new species of dinocysts (Chiropteridium gilbertii, Chytroeisphaeridia hadra, Cleistosphaeridium elegantulum, Cleistosphaeridium palmatum, Dapsilidinium pseudoinsertum, Deflandrea borealis, Evittosphaerula? foraminosa, Ginginodinium? flexidentatum, Hystrichosphaeridium quadratum, Hystrichostrogylon digitus, Impletosphaeridium apodastum, Scalenodinium scalenum, Surculosphaeridium convocatum, Talladinium pellis, Taurodinium granulatum and Trithyrodinium? conservatum), four emendations of dinocyst genera (Alterbidinium, Chatangiella, Chiropteridium and Surculosphaeridium), six new combinations for dinocyst species (Alterbidinium biaperturum, Deflandrea majae, Kleithriasphaeridium mantellii, Simplicidinium insolitum, Spongodinium grossum, Spongodinium obscurum), one new acritarch species (Fromea quadrangularis), one new miospore species (Baculatisporites crenulatus) and one new combination for miospores (Tiliaepollenites crassipites). Most of the taxa included provide age information, almost exclusively last occurrences (range ‘tops’), but some are useful mainly for environmental interpretations. Collectively, they provide a powerful tool for helping to establish the geological history of the Labrador–Baffin Seaway.

Dinoflagellate cysts from the Upper Cretaceous (upper Campanian to lowermost Maastrichtian) of the Middle Vistula River section, Poland

“…A;Niechwedowicz and Walaszczyk 2021). This event illustrates the earliest significant radiation of the genus, which otherwise is more typical of the Paleogene (e.g Fensome et al 2016Fensome et al , 2019b…”

Trithyrodinium verrucosum (Heisecke, 1970) comb. nov., Emend: An Early Paleogene (Danian) Dinoflagellate Cyst Species from the North of Patagonia, Argentina. Regional Stratigraphic and Paleoenvironmental Relevance

“…The systematic classification follows Williams et al (2017). The descriptive terminology follows Fensome et al (2009, 2016). The original photographs from Heisecke (1970) and images from new selected specimens of Trithyrodinium verrucosum from the Roca Formation are illustrated in Figure 2.…”

A Cretaceous dinoflagellate cyst zonation for NE Greenland

“…4). The section contains a low-diversity assemblage, including the brackish water form Nyktericysta dictyophora (former Quantouendinium dictyophorum according to Fensome et al 2016) previously recorded from the Odontochitina ancala Subzone at Svinhufvud Bjerge, Traill Ø (section 36, 37, Nøhr-Hansen, 1993;Figs 2, 3) as Vesperosis aff. V. fragilis.…”

“…The FO of O. porifera may support a Santonian age. O. porifera has a Lower Santonianlower Campanian range in Australia according to Helby et al (1987), whereas Fensome et al (2008) and Fensome et al (2016) recorded an LO of O. porifera in the upper Santonian deposits in the Scotian Margin and Labrador Sea, respectively. The zone may correlate with the lower part of the ?intra-early Coniacianlate Santonian Dinopterygium alatum Interval Zone in the Kveite Formation in the southwestern Barents Sea (Radmacher et al 2014).…”

“…Correlations: McIntyre (1974McIntyre ( , 1975 recorded an Early Maastrichtian FO age for C. diebelii in the Northwest Territories of Canada and a late Campanian -Early Maastrichtian age for W. gracile, his Hystrichosphaeridium sp. 3 and Deflandrea biapertura (now Alterbidinium biaperturum, according to Fensome et al 2016). BioStrat (2018) recorded the FO of Hystrichosphaeridium sp.…”