Foraminíferos del Pliensbachiense en la Sección de Camino (Cuenca Vasco-Cantábrica, España).

Abstract

Foraminiferal assemblages from Pliensbachian (Ibex Zone) to Toarcian (Tenuicostatum Zone, Mirabile Subzone) sedimenis at Camino section (Basque-Cantabrian Basin) are studied. 56 taxa belonging to seven suborders Lave beco identified. Ah of them are searce with the exception of Lacenina that dominates in ah the samples. Ophthalmidiurn nartharnptonensis is for the first time recorded in Spanish Toarcian. The first appearance of Saracene/la sublaevis takes place jo the Margaritatus Zone (Gibbosus Subzone). Typical Pliensbachian species are also found in the Lower Toarcian. Lenhicu/ina toarcense appears for ILe first time in the Spinatum Zone (Hawskerense Subzone). Eoguttu/ina palomerensis and Planularia obonensis are recorded in the Tenuicosiatum Zone (Mirabile Subzone). From Davoei Zone to Tenuicostatum Zone the number of species of Nodosariidae increases and the one of Ichtbyolariidae decreases. i-iigL TOC values are related with a decrease in the foraminiferal abundances and taxonomic diversity. Ah 4w assemblages are poor in number of specimens and species. This impoverishment is due to distinct anoxic evenis with maximun TOC values at lbex Zone and Margaritatus Zone (Subnodosus Subzone).