Up-to-date Spanish continental Neogene synthesis and paleoclimatic interpretation.

Abstract

A synthesis of the Spanish continental Neogene is presented by designing an integrated correlative chart of the Neo> gen-e >succes>Siuns-ofthe >lberian-PeninsuIa-. -Ninemain-sedimentary-breaks-have-been -distinguished-in-most-of-the >basins. They are considered a valuable criteria for correlation as they occur in similar time intervals from basin to basin. The determined sedimentary breaks occur in the Agenian, Ramblian, Middle Aragonian, Late Aragonian, Late Vallesian, Middle Turolian, Late Turolian, Late Ruscinian-Early Villafranchian, and Villafranchian ages. The larger interior basins (Ebro, Tajo, Duero) show a fairly complete Neogene sedimentary record in which the aboye mentioned sedimentary breaks are usually well recognized. A good correlation may be established from basin to basin. Likewise, there is a fairly good correlation among the Upper Miocene-Pliocene sedimentary record of basins spreading out in Levante and southeastern Spain. However, the correlation is not as c1ear in those basins located within the Iberian and Catalan Coastal Ranges, which usually do not show a similar sedimentary pattern. The comparison between Neogene stratigraphic logs in most of the Spanish continental basins and the pattern of global events from currentIy accepted Cenozoic Cyc1e Charts allows recognition of chronological coincidences, especially with regard to the age of seven major sedimentary ruptures (those developed at about 24.5 Ma, 22 Ma, 16 Ma, 13.5 Ma, 9.5 Ma, 5.5 Ma, 3.3 Ma). Evolutionary sedimentary trends in both offshore Mediterranean areas and inland peripheral zones of the Iberian Peninsula show also striking coincidences regarding the chronology of major sedimentary breaks observed in continental successions. Paleoc1imatic curves for the Spanish continental Neogene display four relative temperature peaks indicative of warm c1imatic conditions (Late Agenian, Early-Middle Aragonian, Vallesian-Turolian, and Late Villafranchian) as well as five relatively dry periods (Early Ramblian, Middle-Late Aragonian, Middle Turolian, Late Ruscinian, and Middle Villafranchian ages).