Resumen de Early palaeocene (Danian) dinoflagellates from the Colorado Basin, Argentina
W. A. S. Sarjeant, M.E. Quattrocchio
A palynological investigation of the Maastrichtian?-Palaeocene strata (Pedro Luro Formation), penetrated by Puerto Belgrano No. 20 Borehole in the Colorado Basin of Argentina, yielded 19 species of dinoflagellate cysts and 3 species of acritarchs. On the basis of foraminiferal and nannoplankton dating, the age of the studied levels is Upper Danian. The microplankton assemblage indicates that the Pedro Luro Formation was deposited under relative warm open marine conditions. We propose to attribute the assemblage to palynozone D of Gamerro & Archangelsky, forming the Cerodinium diebeli - Palaeoperidinium pyrophorum Subzone of the Upper Danian. Comparison of the dinoflagellate cyst assemblage with those reported from other areas of southern South America illustrates marked provincialism.
