UKRAINIAN BARRIER-INLET SYSTEMS - THE KEYSTONE OF NON-TIDAL COASTS: FROM CLASSIC STRATIGRAPHIC MODELS TO WAR-ERA RESEARCH

The functionally non-tidal coastlines of the Black and Azov Seas have served as natural laboratories for coastal-geologic research for several centuries. The long history of human settlements, with written accounts dating back >2,000 years provides a unique opportunity for calibrating records of coastal dynamics, including extreme events (storms and tsunamis). A complex geological structure with several neotectonically active segments and multiple fluvial systems resulted in a diverse suite of cliffed coastlines, as well as vast stretches of mixed siliciclastic-bioclastic barriers. This study presents examples of Late Holocene coastal evolutionary models of barrier-liman systems of the northwestern Black Sea that may have impacted the navigation and trade during Greek antiquity. This part of the Ukrainian coast is the site of one of the first barrier-stratigraphic models in the 1880s (transgressive lithosomes). Recent research using georadar and magnetic properties of beach sands is aimed at mapping geo-indicators of erosion (intense storms) within prograded barrier systems. Optical dating suggests periods of historic aeolian aggradation, whereas radiocarbon ages of enclosing mollusk shells reveal reworking from paleo-coastlines dating back to ~40 ka, ~7 ka, and the past 2 ka. To the east of the Gulf of Odessa, the Dnipro-Buh fluvial system, the site of a recent technogenic catastrophe, contributed to a large depocenter, with Kinburn-Tendra-Dzharylgach system being the subject of geoarchaeological research during the Soviet Era. Recent investigations in this region have utilized historical maps, satellite and drone imagery, and field mapping, with an emphasis on non-tidal inlet (prorva) morphodynamics. The mega-barriers of the Crimean Peninsula (e.g., >110-km-long Arabat Spit) and the classic cuspate spit series along the northern Sea of Azov provide examples of barrier morphotypes with varying intensities of anthropogenic impact. The barrier coast of Ukraine is a fragile yet important natural system, its role ranging from serving as an analog of non-tidal coastal lithosomes in the rock record to fulfilling a multitude of recreational and ecological functions. Despite military operations and expanding areas of land and sea mines, coastal research using remotely sensed databases continues.