Bioestrafigrafía de los inocerámidos (Bivalvia) de la Cuenca Navarro-Cántabra y de la Plataforma Norcastellana. Comparación con zonaciones de otras áreas de Europa.

Abstract

The study of 34 sequences and 14 localities in the Navarro-Cantabrian Basin and in the North-Castilian Platform have allowed me to collect more than 1500 inoceramid specimens. The inoceramid study was based on its shell morphology, ornamentation and ontogenetic variation by the Seitz s method. 75 species and subspecies have been identified. The stratigraphic distribution of the inoceramid species and subspecies identified (L pez, 1990b) have allowed me to establish 12 inoceramid assemblages, ranging from the lowermost Turonian to the uppermost Santonian. These assemblages have been compared with those of other european regions, especially with those of northern Germany, established by Seitz (1961, 1965), Keller (1982) and Trtbger (1989). The Wiedmann & Kauffman (1978) inoceramid zonation for northern Spain have been discussed, showing its main problems. On the other hand, the age of some of the litliological formations proposed by Amiot (1982) and Floquet el al. (1982) for this area have been modified by means of the inoceramid information.