Efecto ambiental de variaciones climáticas astronómicas en depósitos hemipelágicos del Eoceno inferior (Sopelana, Bizkaia)
- 1 Universidad del País Vasco / Euskal Herriko Unibertsitatea (UPV/EHU
ISSN: 0213-683X
Año de publicación: 2015
Número: 58
Páginas: 23-26
Tipo: Artículo
Otras publicaciones en: Geogaceta
Resumen
The Eocene successions exposed in Sopelana (Biscay) are characterized by the alternation of hemipelagic limestones and marls organized in thirteen distinctive bundles, each of which contains five limestone-marl couplets. Such an arrangement suggests that the formation of the couplets was driven by astronomical precession cycles (20 ky each) and that of the bundles by eccentricity cycles (100 ky). The couplets within the twelfth bundle were analysed for their carbonate content and their oxygen and carbon stable isotopes, with the aim of deciphering accurately the deep-sea environmental changes caused by the precession and eccentricity cycles and the varying orbital configurations that led to the formation of each bed.