Holocene evolution and sea-level changes in the Battaglia basin area (eastern Gargano coast, Apulia, Italy)

The Battaglia basin (east Gargano-southern Italy) is a former waterbody represented as a lake on historical maps. The detailed study of two cores (BAT1 and BAT2) and additional information obtained from several other drill holes, allowed reconstruction of the Holocene evolution of the basin. The earlier phases date back to before 7000 cal BP, when a high-energy beach developed. Around 6900 cal BP a shallow freshwater body was established. Before 5950 cal BP, sea water flooded the area, initially creating a “sheltered bay”, followed by the “Hydrobiidae and Abra segmentum lagoon”. Around 2700 cal BP freshwater conditions were re-established. The 'Battaglia basin' phase lasted until recent times. Paleoenvironmental information, in combination with 14C dating, made possible the reconstruction of a local Holocene relative sea-level curve showing a continuous rise interrupted, around 2730 yr BP, by an abrupt drop. After that, sea level started again to rise. This evolutionary pattern (rise, fast drop, rise) matches results obtained in other Apulian areas. Although it has not been ascertained that the Holocene Battaglia evolution has been driven by tectonic movements, considering the historical Gargano activity the tectonic hypothesis looks reasonable.