High-resolution magnetostratigraphy and biostratigraphic zonation of the Jurassic/Cretaceous boundary strata in the Puerto Escaño section (southern Spain)

Abstract

This study summarizes the final results of magnetostratigraphic and biostratigraphic investigations of the Tithonian/Berriasian (J/K) boundary limestones at the locality of Puerto Escaño, Spain. The sampled part of the section included a part of magnetozone M20r, full magnetozones M20 n to M18r and a part of magnetozone M18 n.

Especially the detection of two reverse subzones M20 n.1r and M19 n.1r with thicknesses only 40 and 90 mm, respectively, required much effort when sampling the section. The calculated sedimentation rate varied from 1 to 5 mm/ky.

Keywords

• Jurassic/Cretaceous boundary
• magnetostratigraphy
• Ammonites