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We investigated archaeological sites located along the coasts of central Apulia (Italy) to estimate the relative sea level changes which have occurred in this region since the Bronze Age, and test the most recent model of predicted sea level for this region. Surveys focused on six sites located on both the Adriatic and Ionian coasts of Apulia at the feet of the carbonatic Murge plateau, a tectonically stable zone as of the last 125 ka. The sites present the remains of ancient settlements, ranging from the Bronze Age (circa II millennium BC), to the Messapian and Magna Grecia Age (c. 2.5 ka BP), the Roman (c. 2 ka BP) and Middle Ages (c. 1 ka BP). The archaeological sea level markers investigated in these sites provided new insight into the history of the relative sea level changes which have occurred in this region during the last c. 3.3 ka BP. Data from 17 archaeological settlements from the above-mentioned sites, placed above or below the present sea level, were analyzed. The intervening relative sea level changes successive to their construction were estimated via the submergence of the functional elevations of significant architectural features related to the mean sea level at the time during which the settlements were functioning. The r.s.l. changes were estimated using detailed topographic surveys, tide analyses and/or hydrodynamic equations. Although not all archaeological markers allowed univocal interpretations, r.s.l. rise at about 2.25 ± 0.20 m as of the Bronze Age, and at least 0.90 ± 0.20 m in the last 2.0/1.5 ka was estimated. A comparison between the elevation of the marker and two different predicted sea level models seems to confirm a tectonic stability of the investigated region in the last c. 3.3 ka BP.

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., Résumé Pour la détermination des variations du niveau marin durant l'Holocène moyen et supérieur, on croise les données archéologiques, géomorphologiques et radiométriques. Les séquences de dépôts de plage et les plates-formes d'abrasion marines suggèrent que le niveau de la mer se trouvait environ l±0,5 m au-dessus de l'actuel, il y a 7000 à 7500 ans BP. Les vestiges archéologiques ont été utilisés comme indicateurs terrestres et marins du niveau de la mer, les premiers étant représentés par des tombes, des carrières et des citernes, les seconds par des structures portuaires. Les données collectées montrent que le niveau marin était plus bas que -3 ma l'âge du bronze. Les empreintes (catenae) reconnues dans les structures submergées du port de la Rome impériale à Egnatia (1er siècle av. J.-C.) indiquent une position du niveau des plus hautes mers environ 3 m au-dessous de l'actuel. En résumé, la comparaison des données géomorphologiques, archéologiques et radiométriques suggèrent l'existence d'un haut niveau marin correspondant au maximum de la transgression holocène aux environs de 7-7,5 ka BP, suivie d'une baisse jusqu'à l'âge du bronze puis d'une remontée jusqu'à la position actuelle. Ce résultat, en contradiction avec les modèles glacio-eustatiques, pourrait s'expliquer par le fait que le Sud de l'Italie n'a pas été affecté par la réponse isostatique de l'hémisphère Nord à la déglaciation., Auriemma Rita, Mastronuzzi Giuseppe, Sansò Paolo. 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). In: Géomorphologie : relief, processus, environnement, Janvier-mars, vol. 10, n°1. pp. 19-33.

We provide new data on relative sea-level change from the late Holocene for two locations in the central Mediterranean: Sardinia and NE Adriatico. They are based on precise measures of submerged archaeological and tide notch markers that are good indicators of past sea-level elevation. Twelve submerged archaeological sites were studied: six, aged between 2.5 and 1.6 ka BP, located along the Sardinia coast, and a further six, dated ∼2.0 ka BP, located along the NE Adriatic coast (Italy, Slovenia and Croatia). For Sardinia, we also use beach rock and core data that can be related to Holocene sea level. The elevations of selected significant archaeological markers were measured with respect to the present sea level, applying corrections for tide and atmospheric pressure values at the time of surveys. The interpretation of the functional heights related to sea level at the time of their construction provides data on the relative changes between land and sea; these data are compared with predictions derived from a new glacio–hydro-isostatic model associated with the Last Glacial cycle. Sardinia is tectonically relatively stable and we use the sea-level data from this island to calibrate our models for eustatic and glacio–hydro-isostatic change. The results are consistent with those from another tectonically stable site, the Versilia Plain of Italy. The northeast Adriatic (Italy, Slovenia and Croatia) is an area of subsidence and we use the calibrated model results to separate out the isostatic from the tectonic contributions. This indicates that the Adriatic coast from the Gulf of Trieste to the southern end of Istria has tectonically subsided by ∼1.5 m since Roman times.