Hydrogeological and climatological study of the atmothermal springs of the Amarantos area, Northwest Greece

Abstract

In the region of the village Amarantos, northwest Greece, within an area of ca. 2000 m 2 at an altitude of 1260 m, hot, wet air escapes from the ground. These streams of air are called locally “atmothermal” springs and this term is used in this study. This mountainous and woody region consists geologically of limestones and flysch of the Olonos-Pindos zone and ophiolites and limestones, with schist-flint intercalations of the Subpelagonic zone. The springs of hot, wet air appear at the tectonic contact (fault) of the limestones and flysch of the Olonos-Pindos zone. At lower altitudes in the area, thermomineral water springs are found. The steam from these underground thermomineral waters, flowing at shallow depth, ascends through the solution channels of the limestone and the fault, and emerges there. The temperature and the relative humidity of the atmothermal air at the exits have mean values of 38°C and 97–100%, respectively. The exit velocity of the hot air varies between 0.2 and 3.7 m s −1, depending on the geometric dimensions of each crack and its position relative to the fault. This hot air has an electric conductivity of 10–20 μS cm −1 and contains Rn (5.5–6.0 Mache). The total flow rate from the cracks is estimated to be approximately 10, 000 m 3 h −1. The climate of the area can be characterized as a mountainous, transitory climatic zone—between the humid continental warm summer and the Mediterranean climates, with a variety of microclimates. Conditions of bioclimatological comfort prevail from the end of April till the beginning of October. This phenomenon, the only one known in Greece, in combination with the bracing climate of the area offers a good possibility for the creation of a modern and complete steam-bath sanatorium.