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Abstract Tertiary (Palaeogene and Neogene) deposits crop out widely across both the Iberian peninsula and the Balearic Islands (Fig. 13.1 ), and record a dramatic sequence of events during plate convergence. The anticlockwise rotation of an initially isolated Mesozoic Iberian plate was followed by late Cretaceous– Cenozoic interaction with both the European and African plates. This ultimately created two great Alpine mountain belts (Pyrenean-Basque-Cantabrian and Betic-Balearic) (Fig. 13.1 ), each of which generated major Cenozoic foreland basins (Ebro and Guadalquivir). Away from these mountain belts, two large Cenozoic intraplate depressions (Duero and Tajo basins) flank a central horst (Central Range). Another important group of depocentres occurs within a string of Neogene grabens situated along the eastern side of mainland Spain (Fig. 13.1 ), forming part of a long-lived and still-active extensional system linking the Valencia trough with the Rhine and Rhone grabens in Germany and France. Further SE, Neogene extension propagated from the Valencian trough into the southern Betic orogen and created a series of basins from Alicante to Granada and beyond. Tertiary sedimentary rocks in Spain were thus deposited during and after Alpine compression in the Iberian area. This chapter summarizes the main characteristics of these sediments, moving broadly from north to south, a direction reflecting the diachronous shift in Cenozoic Alpine deformation from the Pyrenees to the Betic-Balearic region.

Abstract Paleocene sediments are not thick in the Spanish Basque Country (usually less than 200 m), largely composed of stacks of hemipelagic limestones and marls deposited in a clastic-starved deep basin. In addition to these, resedimented carbonates accumulated on base-of-slope aprons girding the basin, and resedimented carbonates plus lesser amounts of coarse-grained siliciclastics discontinuously plugged a deep-sea channel system incised on the basin floor. Third-order depositional sequences that attest to sea-level changes have earlier been recognized in the apron and channel systems (Pujalte et al., 1993). Further analyses have now demonstrated that these sea-level changes are also expressed in the hemipelagic sections by means of basin-wide variations in sedimentation rates through time, relative proportions of limestones and marls and, locally, the type of turbidite intercalations. The building blocks of these sequences are high-order stratification cycles, probably tuned to Milankovitch frequencies. Since these hemipelagic sections contain a nearly continuous stratigraphic record, a reliable reconstruction of the Paleocene sea-level changes that affected the Basque basin has been possible. A good match has been found between the regional sea-level curve derived from the deep-sea record and that of the global chart of Haq et al. (1988), mainly based on coastal onlap. This correlation clearly demonstrates that the signature of sea-level changes can be confidently unravelled from deep-marine successions, though it remains to be seen whether it reflects an eustatic signature or a bias of the data base.