Search

Submerged cultural heritage provides a unique opportunity to couple paleoenvironmental and culture-his-torical research with the contemporary cultural heritage needs of the public where field work takes place. Greece provides an ideal locale for developing what we refer to as maritime cultural heritage asset districts (MCHAD). Here we summarize two seasons (2019, 2021) of field survey work in the Methoni Bay region of Messenia off the southwestern Peloponnesus coast that provides an ideal locale for developing a MCHAD. A number of interdisciplinary survey tools were used to examine cultural and adaptive responses to environ-mental and cultural change in deep-time around the Methoni Bay with the aim of enhancing cultural heritage tourism in the area. Our project builds on earlier paleogeography and submerged heritage research by con-ducting: 1) non-invasive high definition shallow marine geophysics including Multibeam Echosounder, Side Scan Sonar, and Chirp sub-bottom profiler; 2) photogrammetry of several previously investigated shipwrecks and a unique submerged Middle Bronze Age/Middle Helladic (MH) settlement (2050/2000 – 1750/1680 BCE) using a three camera custom rig mounted on a scuba scooter for large area coverage; 3) shallow submerged sediment sampling using scuba and diver operated coring device to study the deep-time environmental his-tory of the Methoni embayment and preliminary terrestrial coring using a Cobra percussion core drilling sys-tem; and 4) a cyber-archaeology workflow using photogrammetry and 3D laser desktop scanning tools to collaborate with a local museum to curate and disseminate research for the public. This article provides an overview of the project methods and preliminary results for melding scientific research with cultural heritage objectives.

Numerous karst depressions exist along the Croatian coast of the eastern Adriatic and many have been submerged due to the Holocene sea- level rise. They may be connected or isolated from the sea in relation to the variations in relative sea-level (RSL) and their sill depth. When RSL is lower than the sill depth, depressions become isolated from the direct marine influence and freshwater environments may form. As the sea level rises, brackish- water phase occurs due to the seawater intrusion through karst. When RSL reaches the sill depth, depressions become flooded and marine deposition starts. Thus, sediments preserved in karst depressions can be a valuable source of paleoenvironmental and RSL data. The coastal areas of the Mljet Island, Lošinj Channel and Pirovac Bay are typical examples of submerged karst environments with sills at different depths. We provide a sedimentological record based on the multi- proxy analysis of 10 piston cores, combined with high resolution seismic data. The dated sediment successions enabled differentiation of freshwater, brackish-water and marine environments that existed in the studied areas during the Late Pleistocene and Holocene. We observed ingression contacts (i.e., onset of marine deposition) in each analyzed sediment core. In the Lošinj Channel we dated the oldest ingression contact at 10.5 ky BP, with sill at depth of 50 m. In the Stupa Bay on the Mljet Island this contact was dated at 9.8 ky BP in a basin with a sill depth of 19 m. Smaller sub- basin in the Lošinj Channel was ingressed at 7.9 kyr BP, similar as Pirovac Bay. The youngest ingression contacts were recorded in sediment cores from small sub-basins with shallow sills in the Lošinj Cannel and Veliko jezero on the Mljet Island. The collected data enabled us to infer RSL by combining the radiocarbon dates from the ingression contacts and sill depths. Current and future work includes detailed investigations of the other locations along the eastern Adriatic coast (e.g., Telašćica Bay, Kornati Channel, Koločep Channel) which are characterized by similar geomorphology. The composite RSL record obtained from different locations can improve our understanding of the Adriatic RSL and palaeoenvironmental changes, especially at the beginning of the Holocene for which only few data exist in this area.

Quaternary stratigraphy and sea level changes have been extensively investigated in many areas of the Mediterranean. However, numerical dating of coastal deposits and the associated paleoenvironmental information are limited for the coasts of Cyprus, principally based on radiometric and radiation-exposure geochronological techniques on fossils which bear a range of limitations and uncertainties. As such, optically stimulated luminescence (OSL) dating techniques are deemed to be the most suitable in direct dating of the coastal sediments of Cyprus. In the southeastern Cyprus, coastal dunes (aeolianites) now forming elongated ridges appear as morphological features running parallel to the current shoreline presenting an indicator of sea level and climate changes of great paleoenvironmental significance. We present our first chronological results for the exposed aeolianites and underlying littoral deposits formed along the southeastern coastal Cyprus ranging from 78.4 ± 9.9 to 56.2 ± 7.4 ka. The post-infrared–infrared stimulated luminescence (pIR-IRSL) revealed that dune formation took place during the marine isotope stages (MISs) 3, 4, and possibly 5a. Late Holocene reworking is proposed for a distinctively isolated dune with an age of ~1.3 ka ago. This study also showed that pIR-IRSL dating of feldspars may be a reliable alternative to quartz OSL dating when the quartz luminescence characteristics are unsuitable. © 2016, Springer-Verlag Berlin Heidelberg.

International audience

Combined micropaleontological and geochemical analyses of the high-sedimentation gravity core M-4G provided new centennial-scale paleoceanographic data for sapropel S1 deposition in the NE Aegean Sea during the Holocene Climatic Optimum. Sapropel layer S1a (10.2–8.0 ka) was deposited in dysoxic to oxic bottom waters characterized by a high abundance of benthic foraminiferal species tolerating surface sediment and/or pore water oxygen depletion (e.g., Chilostomella mediterranensis, Globobulimina affinis), and the presence of Uvigerina mediterranea, which thrives in oxic mesotrophic-eutrophic environments. Preservation of organic matter (OM) is inferred based on high organic carbon as well as loliolide and isololiolide contents, while the biomarker record and the abundances of eutrophic planktonic foraminifera document enhanced productivity. High inputs of terrigenous OM are attributed to north Aegean borderland riverine inputs. Both alkenone-based sea surface temperatures (SSTs) and δO18 G. bulloides records indicate cooling at 8.2 ka (S1a) and ~7.8 ka (S1 interruption). Sapropelic layer S1b (7.7–6.4 ka) is characterized by rather oxic conditions; abundances of foraminiferal species tolerant to oxygen depletion are very low compared with the U. mediterranea rise. Strongly fluctuating SSTs demonstrate repeated cooling and associated dense water formation, with a major event at 7.4 ka followed by cold spells at 7.0, 6.8, and 6.5 ka. The prominent rise of the carbon preference index within the S1b layer indicates the delivery of less degraded terrestrial OM. The increase of algal biomarkers, labile OM-feeding foraminifera and eutrophic planktonic species pinpoints an enhanced in situ marine productivity, promoted by more efficient vertical convection due to repeated cold events. The associated contributions of labile marine OM along with fresher terrestrial OM inputs after ~7.7 ka imply sources alternative/additional to the north Aegean riverine borderland sources for the influx of organic matter in the south Limnos Basin, plausibly related to the inflow of highly productive Marmara/Black Sea waters. © 2015, Springer-Verlag Berlin Heidelberg.

We present a study on four high sedimentation-rate marine cores with suppressed bioturbation effects, recovered along the northern margin of the eastern Mediterranean. We demonstrate that this region, central to the development of modern civilisation, was substantially affected throughout the Holocene by a distinct cycle of cooling events on the order of 2o C. In the best-preserved cases the onset of these events appears particularly abrupt, within less than a century. The cooling events typically lasted several centuries, and there are compelling indications that they were associated with increased aridity in the Levantine/NE African sector (Rossignol-Strick, 1995; 1998; Alley et al., 1997; Hassan, 1986; 1996; 1997a,b; McKim Malville et al., 1998). Several of these episodes appear coincident with cultural reorganisations, with indigenous developments (eg. cattle domestication, new technologies) and population migrations and fusion of peoples and ideas (Hassan, 1986; 1996; 1997a,b; McKim Malville, 1998). We infer that climatic events of a likely high-latitude origin (O’Brien et al., 1995; Bond et al., 1997; Mayewski et al., 1997; Alley et al., 1997) caused cooling and aridity in and around the eastern Mediterranean via a direct atmospheric link, and therefore played an important role in the development of modern civilisation.

The present study presents the results of the preliminary marine geophysical survey conducted in 2006 at the gulf of Sounion, southern Attica, Greece. The site is of great archaeological importance since cape Sounion served as a navigational landmark and a naval fortress protecting the sea-lanes towards the metropolis of Athens and the silver mines of Lavreotiki during the Classical and Hellenistic periods. Parts of the coastal ancient installations are now submerged. The results of the collected geophysical data include the examination of the seafloor texture and stratigraphy. Therefore a geomorphological map of the gulf was constructed based on the configuration of the substrate and the seafloor stratigraphy. Archaeological remains lying on the seafloor have been detected on the sonographs and have been correlated with the results of previous studies. The development and the evolution of the gulf during the prehistoric period were evaluated via the sea floor stratigraphy and the prediction of sea level change in the area based on the eustatic and glacio-hydro-isostatic response. The sea level change during the historic period was examined and a relative sea level rise of at least 2,5-3,0 m was suggested for the last 2500 years based on the marine geophysical survey results.