3D mapping of geological heritage: the case of the mythical waterfall of Styx

Preserving heritage constitutes an issue of utmost importance for humanity. Besides the conventional forms of tangible and intangible culture, UNESCO Global Geoparks are considered as natural cultural heritage sites of exceptional geological importance. Nowadays, remote sensing has proven to be an effective, cost-efficient and non-invasive tool with great potentialities for the monitoring, and thus protection and management of such areas, contributing to their sustainable development. In this framework, Unmanned Aerial Vehicle (UAV) and Terrestrial Laser Scanning (TLS) data were utilized to map the geosite of Chelmos – Vouraikos UNESCO Global Geopark (UGGp) “Styx waters”. The waterfall of Styx is one of the most important geosites of Chelmos – Vouraikos UGGp and Greece as well, located at the north-eastern end of Chelmos Mountain, and one of the most important geomythological sites known as the entrance to Hades and where Thetis, Achilles mother, dipped him in its waters holding him from its heel to make him immortal. Styx Waters, are the springs of Krathis river, coming out at an altitude of 2100 m as a waterfall, falling down rapidly for almost 200 m to the base of the vertical cliff where a small cave is found. The main objective of the research was the digitalization of the geosite in order to create a digital counterpart, easily accessible to people who do not have the opportunity to visit it physically. Specifically, a UAV campaign and a TLS survey were performed using a DJI Phantom 4 Pro quadcopter and a Leica BLK360 sensor. The collected data were processed appropriately, resulting in the generation of 3D representations of the geosite.