Five areas have been selected for sampling: Pikrolimni (Central Macedonia, N. Greece), Melos and Kea (Cyclades), Sousaki (Attica) and Kyllini (Peloponnese) representing representing different geological environments. Pikrolimni is a small alkaline lake characterized by deposition of terrestrial evaporite minerals such as natron. Sampling involved muds in the periphery of the lake, which have been reported to contain natron. Sampling in Melos and Sousaki was focused on active solfataras. In Melos two types of samples were collected, a) materials in the close proximity to solfataras (Kalamos, Fyriplaka and Paleochori areas), in galleries (Kalamos and Fyriplaka) and open terrains (Paleochori) and b) clays from a kaolin deposit (Loulos) and a bentonite deposit (Aggeria). The clay samples did not display any evidence of solfatara activity and will be used as controls. In the Sousaki area samples were collected next to the solfatara.
In Kyllini, sampling involved organic muds in the vicinity of the Roman baths. The muds were collected from pools and were dark grey to black due to the abundance of organic matter. Finally, in Kea, sampling was performed in the Orkos bay in the eastern part of the island. Samples were collected from galleries in abandoned Fe-mines. The Fe-ores correspond to gossans in the boundary between marbles and mica-schists belonging to the blueschist unit of the Cyclades. The samples are red or yellow and fine grained and correspond to weathering of Fe-rich horizons of the mica schists.
The mineralogical composition of the samples (both qualitative and quantitative) will be determined by X-ray diffraction. The chemical composition of the samples will be determined by ICP-MS.
SEM Images from top left: crystals of Kalamos, Melos fumarolic sulphur, scale= 200microns across field of view; top right : Kalamos, melos alunogen scale bar= 50microns; Kalamos, Melos K-alum scale bar= 10microns. (images by Effie Photos-Jones).