Neolithic to modern period palaeogeographic transformations in southern Danube delta and their impact on human settlements in the Enisala-Babadag region

Abstract

Archaeological data provide evidence of human inhabitation in the Danube Delta since the Early Neolithic with once flourishing human settlements such is the case of Enisala and Babadag settlements. Their remains dating back from Eneolithic (Enisala) or Iron Age (Babadag) or from their revivals in Antiquity and Medieval Age have been found on higher grounds (i.e. hillslope terrace) in the immediate vicinity of Babadag and Razelm lakes and of the reedmarsh developed in-between the lakes. The settlements benefited from their strategical position defined by the intersection of the terrestrial routes linking the northern and southern Dobrudja with the navigation ways to the Black Sea via a shallow but open lagoon prior to Antiquity and later, post 7th c. BC, via Dunavăț branch of the Danube that extended the southern delta by successive open-coast deltaic lobes formation (2600-1300 yrs BP).This study documents the landscape transformation of the region since Early Neolithic to the present, based on sedimentological, chronostratigraphic, mineralogical, geochemical, magnetometric, macro- and microfauna analyses which altogether led to the identification of main stages: i) high floodplain (before 8000 BP), ii) wetlands (8000-7500 yrs BP), iii) shallow marine bay (7500–6000/5500 yrs BP), iv) lagoon (5500-460 yrs BP) and v) reedmarsh (460 yrs BP – present). Each type of landscape that succeeded in the Enisala-Babadag region is described in relation with shoreline position, (ground)water depth and Danube Delta development. Additionally, the tectonic subsidence of the studied wetlands (0.5–0.8 mm/yr) was assessed and its effects on the landscape changes and long-term morphodynamics are discussed.