Middle to Late Holocene relative sea-level changes recorded on the coast of Apulia (Italy) / Variations relatives du niveau marin pendant l'Holocène moyen et supérieur le long des côtes méridionales des Pouilles (Italie)

Abstract

Abstract This paper uses a combination of archaeological, géomorphologie and radiometric data from the coast of Southern Apulia between Bari and Taranto for the reconstruction of sea-level changes during the middle and late Holocene. In particular, beach sequences and wave- cut platforms suggest a relative sea-level highstand at about 1 ± 0.5 m a.s.l. at about 7.0-7.5 ka BP. Archaeological remains have been used as land or sea level indicators, the former represented by tombs, quarries, cisterns, the latter by harbour structures. The collated data show that sea level was lower than -3 m during the Bronze Age; the catenae casts recognised on the submerged structures of the Roman imperial harbour of Egnatia (1st century ВС) indicate a position of high tide sea level at about 3 m below present mean position. In summary, the comparison between géomorphologie, archaeological and radiometric data suggests a high sea-level stand corresponding to a maximum Holocene transgression at about 7.0-7.5 ka BP followed firstly by a fall of sea level until the Bronze Age and then by a rise to the present position. This evidence is in contrast with the results of glacio-eustatic models and could be due to the fact that southern Italy is not involved in the flexural response to Northern Hemisphere déglaciation.