Long-term evolution of western Laconia Peninsula through an integrated geomorphological and geoarchaeological analysis

This research aims to reconstruct the sea-level oscillations that occurred since the Late Pleistocene along the western coast of Laconia, a tectonically active region located in SE Peloponnese. This area exhibits a prominent marine terrace sequence, which serves as a key marker for understanding regional landscape evolution during Marine Isotope Stage 5 (MIS 5). Additionally, some geoarchaeological evidence witnesses the Holocene coastal morphology. According to previous studies, the uplift of this area can be considered a signal of the subduction of the African lithosphere beneath the Eurasian plate.

To analyse the terrace system, a combination of direct and indirect survey techniques was employed across eight sites. Firstly, the marine terraces were extensively identified and mapped by GIS and machine learning analysis, then detailed field-mapping and DGPS mtechniques were carried out in some strategic points along the entire coastal sector. Optically Stimulated Luminescence (OSL) dating is going to be performed on a caprock sample, whose elevation is consistent with the one of a terrace order investigated in previous studies in order to corroborate their MIS 5 dating. Lastly, remote sensing and aerial imagery interpretation were utilized to detect the seabed morphology for the analysis of Holocene trends.

The results underline three MIS 5 high stands at 8 ± 2, 16-24 ± 2, and 40-50 ± 2 m asl, widely documented by well-shaped terraces along the whole region.

Furthermore, the submerged prehistoric settlement remains of Pavlopetri and Plytra at different depths demonstrate Holocene sea-level stands testifying a local subsidence, whose occurrence is supported also by the presence of three submerged beachrocks in the Bay of Vatika (Pizarro et al. 2012).

The findings from geomorphological analysis confirm a homogeneous long-term tectonic behaviour in the entire emerged coastal area, providing a broader regional context for the terrace system evolution, while the geoarchaeological analysis suggests recent local subsidence in specific submerged sectors.

The proposed methodology provides a robust framework for the paleo-landscape and sea-level reconstruction since MIS 5 at a regional scale through a comprehensive analysis of terrace distribution and submerged archaeological remains by integrating new technology, GIS and AI analyses.