Geological and Hydrogeological Settings of springs in Samaria Gorge (western Crete, Greece)

Abstract

Samaria Gorge is located in the southern and western parts of the prefecture of Chania, in the White Mountains (Western Crete), and forms the main structure of one of the most important National Parks of Greece. It extends for approximately 13 kilometres, with a general N-S direction and exposes one of the essential lithostratigraphic sections of the Plattenkalk Group, the tectonically lowermost paraautochthonous group of metamorphosed rocks that structure the core not only of the White Mountains of Western Crete but also of the major mountains of the island (Tallaia, Psiloritis, Lasithiotika). The gorge runs through a stream that starts about 2 km north of the settlement of Samaria and flows downstream to the sea. In some places, the stream flows subsurface and reappears at topographically lower positions. This situation continues up to Kefalovrysia location , where the stream flows up the riverbed to the Sooth Cretan Sea. During the wet season of the year, the stream receives large amounts of water from the watershed, while during the dry season, it receives the outflows of a relatively small number of springs scattered along the Samaria Gorge. Based on the aforementioned, the main water source during the summer season comes from the the springs, located in the metamorphosed carbonate rocks with siliceous interlayers of the Plattenkalk Group. The tourist development of the area (with an increasing trend of tourists passing through the gorge), combined with the need to preserve the highest natural beauty of the area, requires full fire safety as well as an improvement of the provided tourist services, which inextricably depends on the quantity and quality of the area’s available water in the various stops of the thousands of tourists inside the gorge as well at its southern exit (Agia Roumeli settlement), where the route terminates. In order to cover to the maximum extent the water supply - hygiene needs of the thousands of tourists, the local community needs both the coverage of any firefighting requirements and the rational management of the existing water resources, as well as the investigation for additional water resources from potential underground aquifers. Therefore, collecting as much information as possible, related to the springs located within the gorge, is necessary. Beyond their spatial distribution, it is essential to determine the quantitative and qualitative features of the water of each spring. At the same time, the mapping around the springs is also crucial, where the steep topographical relief favours this procedure. This mapping will contribute help to the interpretation of the spring's formation. The presentation and discussion of the conclusions related to the spring's geological mapping within the Samaria gorge is the paper's objective. Acknowledgment: This research is financially supported by the Green Fund “Forest Protection and Upgrading 2019” under “Other Nationals. Green Fund”.