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- Early and Middle Jurassic palynostratigraphy of the Lusitanian Basin in the proto-Atlantic contextPublication . Correia, Vânia; Pereira, Zélia; Riding, James; Duarte, L. V.; Henriques, Maria Helena; Fernandes, PauloSUMMARY: A palinologia é uma ferramenta muito útil nos trabalhos de bioestratigrafia e interpretações paleoambientais, e que pode ser aplicada no conhecimento da geologia da Bacia Lusitânica. Assim, foi desenvolvido um estudo palinoestratigráfico de alta-resolução em 8 cortes do Jurássico Inferior e Médio (Sinemuriano superior—base do Batoniano) da Bacia Lusitânica e, neste trabalho, são apresentados os intervalos de ocorrência e bioeventos associados aos principais taxa identificados, nomeadamente no grupo dos quistos de dinoflagelados.
- The Middle Jurassic dinoflagellate cyst biostratigraphy of the Lusitanian Basin, Portugal [Resumo]Publication . Correia, Vânia; Riding, James; Henriques, Maria Helena; Fernandes, Paulo; Pereira, Zélia; Wiggan, N.J.ABSTRACT: A mainly Middle Jurassic composite succession with 129 samples was examined palynologically. This spans the Toarcian–Aalenian transition to the lowermost Bathonian, exposed at Cabo Mondego (includes the GSSP and the ASSP for the Bajocian and Bathonian stages respectively) and São Gião in the northern Lusitanian Basin, western Portugal. The main goal was to establish a biostratigraphical scheme based on dinoflagellate cysts bioevents.
- The effects of the Jenkyns Event on the radiation of Early Jurassic dinoflagellate cystsPublication . Correia, Vânia; Riding, James; Duarte, L. V.; Fernandes, Paulo; Pereira, ZéliaABSTRACT: This contribution is an overview of the Early Jurassic dinoflagellate cysts of the Lusitanian Basin in Portugal, with particular emphasis on the effects of the Jenkyns Event (Toarcian Oceanic Anoxic Event) on the evolution of this planktonic group. We review and discuss data from 214 samples from six Lower Jurassic successions (upper Sinemurian to upper Toarcian) in the Lusitanian Basin. The late Pliensbachian radiation of dinoflagellate cysts was well recognized in this basin. The pre-Jenkyns Event interval is highly productive, with maximum abundance and species richness values. However, this palaeoenvironmental perturbation severely affected the evolution of this group for the remainder of the Early Jurassic. The prolonged recovery of the dinoflagellates in the Toarcian following the Jenkyns Event is not typical of the northern regions (Arctic and Boreal realms), where new species began to evolve earlier compared with southern European basins.
- The Early and Middle Jurassic palynostratigraphy of the Lusitanian Basin (Portugal) in a proto-Atlantic contextPublication . Correia, Vânia; Pereira, Zélia; Riding, James; Duarte, Luis; Henriques, Maria Helena; Fernandes, PauloABSTRACT: Palynomorphs, especially dinoflagellate cysts, are important biostratigraphical and palaeoenvironmental tools and their study can be applied to the Lusitanian Basin of Portugal. A palynostratigraphical high-resolution survey was undertaken in eight Lower and Middle Jurassic (upper Sinemurian to lowermost Bathonian) sections from the Lusitanian Basin. We present the resulting biostratigraphical scheme comprising the most significant palynomorph bioevents for this interval.