Dinoflagellate cysts from the Cretaceous–Paleogene boundary at Ouled Haddou, southeastern Rif, Morocco: biostratigraphy, paleoenvironments and paleobiogeography

Abstract

A palynological investigation of a section dated by foraminifera, at Ouled Haddou, south-eastern Rifian Corridor, northern Morocco, revealed a rich and well-preserved dinoflagellate cyst assemblage that allowed a palynological separation of Maastrichtian from Danian deposits. The gradual change of the dinoflagellate cyst assemblages and the biostratigraphic resolution attained, suggest that the studied Maastrichtian-Danian section is continuous. The recognition of the latest Maastrichtian and earliest Danian is based on global dinoflagellate cyst events, including the first occurrence of the latest Maastrichtian species Disphaerogena carposphaeropsis, Glaphyrocysta perforata, and Manumiella seelandica, the latest Maastrichtian acme of Manumiella seelandica, and the first occurrence of the earliest Danian markers Carpatella cornuta, Damassadinium californicum, Eisenackia circumtabulata, Membranilarnacia tenella and Senoniasphaera inornata. The Cretaceous-Paleogene boundary is placed above the latest Maastrichtian events, mainly immediately above the acme of M. seelandica and below the earliest Danian events, particularly below the first occurrences of C. cornuta and D. californicum. The biostratigraphic interpretations are based on a comparison with calibrated dinoflagellate cyst ranges from several reference sections, mainly in the Northern Hemisphere middle latitudes. The Cretaceous-Paleogene boundary is not marked by a mass extinction of dinoflagellate cyst species, but shows important changes in the relative abundances of different species or groups of morphologically related species. These changes are paleoenvironmentally controlled. The peridinioid assemblage suggests deposition in a subtropical to warm temperate province. One dinoflagellate cyst species, Phelodinium elongatum, is formally described.

Similarities of the K/Pc dinoflagellate cyst associations between South Atlantic and Indian proto-oceans

“…Distribution of dinoflagellate species in both hemispheres are interpreted as a result of bipolar migration of this species in response to the global warming during the early Danian (Smit and Brinkhuis, 1996;Nøhr Hansen and Dam, 1997;Brinkhuis et al, 1998;Willumsen, 2006;Slimani et al, 2010).…”

“…The species of Glaphyrocysta were considered as indicators of a nearshore shallow marine environment (Brinkhuis and Zachariasse, 1988;Eshet et al, 1992;Slimani et al, 2010). Glaphyrocysta texta (Figures 2, 4C, Tables 1, 2A) is present only in India in the Early Cretaceous (Mehrotra and Sarjeant, 1987).…”

Palynomorphs of the First Down-Hole Shale Occurrence in Three Contiguous Basins in Nigeria: Implication on the K-Pg Boundary

“…2010). Notwithstanding, records show that the K-Pg boundary is not marked by a mass extinction of dinoflagellate cyst species, but shows important changes in relative abundances of different species or group of morphologically related species in a section in northern Mexico (Slimani et al, 2010). The dynamics of the plant cover is another major component of the biological response across the K-Pg interval and associated destabilization worldwide suggesting the usefulness of palynology in the identification of the boundary.…”

Dinoflagellate cysts and palynofacies across the Cretaceous-Paleogene boundary interval of the Vrancea Nappe (Eastern Carpathians, Romania)

“…In con trast to the ter res trial fauna (di no saurs), as well as most aquatic or gan isms (cal car e ous plank tonic foraminifera, nannoplankton, etc), or ganic-walled dinoflagellate cyst taxa did not un dergo a mass ex tinc tion across the K-Pg bound ary (Benson, 1976;Hansen, 1977;De Coninck and Smit, 1982;Hultberg, 1985;Firth, 1987;Brinkhuis and Zachariasse, 1988;Moshkovitz and Habib, 1993;Habib et al, 1996;Gedl, 2004;Slimani et al, 2010). Biostratigraphical stud ies of this bound ary based on the dinoflagellate cysts have been made at sev eral Tethyan (Brinkhuis and Zachariasse, 1988;Gedl, 2004;Egger and Mohamed, 2010;Slimani et al, 2010Slimani et al, , 2016Mohamed et al, 2012M'Hamdi et al, 2013;Mohamed and Wagreich, 2013;Slimani and Toufiq, 2013;Guédé et al, 2014) and bo real (Hansen, 1977;Moshkovitz and Habib, 1993;Brinkhuis and SchiÝler, 1996;Habib et al, 1996;Slimani, 2001;Slimani et al, 2011) geo log i cal sec tions.…”

“…Biostratigraphical stud ies of this bound ary based on the dinoflagellate cysts have been made at sev eral Tethyan (Brinkhuis and Zachariasse, 1988;Gedl, 2004;Egger and Mohamed, 2010;Slimani et al, 2010Slimani et al, , 2016Mohamed et al, 2012M'Hamdi et al, 2013;Mohamed and Wagreich, 2013;Slimani and Toufiq, 2013;Guédé et al, 2014) and bo real (Hansen, 1977;Moshkovitz and Habib, 1993;Brinkhuis and SchiÝler, 1996;Habib et al, 1996;Slimani, 2001;Slimani et al, 2011) geo log i cal sec tions. Other K-Pg sec tions are from New Zea land (Willumsen, 2004(Willumsen, , 2011 in the South ern Hemi sphere.…”