ABSTRACT The aim of the current study is to examine the role played by Thorikos within the Laurio... more ABSTRACT The aim of the current study is to examine the role played by Thorikos within the Laurion silver mining area from the perspective of metallurgical activities during the Classical and Early Hellenistic periods. Because water availability directly determines the production output of metallurgical workshops, a hydrological analysis of the area is an ideal tool to enhance our understanding of this issue. On a large scale, hydrological modelling is accomplished through the analysis of runoff water accumulation; on a small scale, a water balance model is used to simulate the operated water supply system for industrial purposes, more specifically the purifying of silver ores in washeries. Also, the impact of cistern location on its effectiveness and usability for silver processing is explored. The two focus areas are the Velatouri Hill, where the site of Thorikos is located, and the Soureza Valley, which is situated in the centre of the Laurion. In each area a number of ore washing workshops were chosen to study in more detail. Through the region-wide hydrological and archaeological analysis, it could be shown that the Thorikos workshops contrast sharply with the Soureza ones. The latter relied on ephemeral streams which were consolidated and tapped by large cisterns, thus creating a water stock that was more than sufficient to bridge the dry periods of the year. The former relied on the harvesting of limited runoff during heavy rain events, which in many cases did not provide a sufficient water stock. Furthermore, water supply strategies in Thorikos were not as well-considered in comparison to Soureza. This leads to the conclusion that Thorikos could have never been the large scale processing site Soureza was and, when combined with the small-scale analysis, the site must have had a distinctively more ad hoc character.
Recent studies using water-stable isotopes (δ18O and δ2H) have suggested an ecohydrological separ... more Recent studies using water-stable isotopes (δ18O and δ2H) have suggested an ecohydrological separation of water flowing to streams or recharging groundwater and water used by trees, known as the 'two water worlds' (TWW) hypothesis. In this study, we measured water isotopic composition in precipitation [open field and throughfall, i.e. local meteoric water line (LMWL)] and the mobile water compartment (i.e. stream and soil solution), bulk soil water and xylem water over a period of 1.5 years in two headwater catchments: NF, covered with old growth native evergreen forest (Aetoxicon punctatum, Laureliopsis philippiana and Eucriphya cordifolia), and EP, covered with 4 and 16-year-old Eucalyptus nitens stands. Our results show that precipitation, stream and soil solution plot approximately along the LMWL, while xylem waters from all studied tree species plot below the LMWL, supporting the TWW hypothesis. However, we also found evidence of ecohydrological connectivity during the wet season, likely controlled by the amount of antecedent precipitation. These observations hold for all investigated tree species. On both sites, a different precipitation source for stream and xylem water was observed. However, in EP, bulk soil showed a similar precipitation source as xylem water from both E. nitens stands. This suggests that E. nitens may use water that is recharging the bulk soil compartment. We conclude that under a rainy temperate climate, the TWW hypothesis is temporal and does not apply during wet seasons.
ABSTRACT The aim of the current study is to examine the role played by Thorikos within the Laurio... more ABSTRACT The aim of the current study is to examine the role played by Thorikos within the Laurion silver mining area from the perspective of metallurgical activities during the Classical and Early Hellenistic periods. Because water availability directly determines the production output of metallurgical workshops, a hydrological analysis of the area is an ideal tool to enhance our understanding of this issue. On a large scale, hydrological modelling is accomplished through the analysis of runoff water accumulation; on a small scale, a water balance model is used to simulate the operated water supply system for industrial purposes, more specifically the purifying of silver ores in washeries. Also, the impact of cistern location on its effectiveness and usability for silver processing is explored. The two focus areas are the Velatouri Hill, where the site of Thorikos is located, and the Soureza Valley, which is situated in the centre of the Laurion. In each area a number of ore washing workshops were chosen to study in more detail. Through the region-wide hydrological and archaeological analysis, it could be shown that the Thorikos workshops contrast sharply with the Soureza ones. The latter relied on ephemeral streams which were consolidated and tapped by large cisterns, thus creating a water stock that was more than sufficient to bridge the dry periods of the year. The former relied on the harvesting of limited runoff during heavy rain events, which in many cases did not provide a sufficient water stock. Furthermore, water supply strategies in Thorikos were not as well-considered in comparison to Soureza. This leads to the conclusion that Thorikos could have never been the large scale processing site Soureza was and, when combined with the small-scale analysis, the site must have had a distinctively more ad hoc character.
Recent studies using water-stable isotopes (δ18O and δ2H) have suggested an ecohydrological separ... more Recent studies using water-stable isotopes (δ18O and δ2H) have suggested an ecohydrological separation of water flowing to streams or recharging groundwater and water used by trees, known as the 'two water worlds' (TWW) hypothesis. In this study, we measured water isotopic composition in precipitation [open field and throughfall, i.e. local meteoric water line (LMWL)] and the mobile water compartment (i.e. stream and soil solution), bulk soil water and xylem water over a period of 1.5 years in two headwater catchments: NF, covered with old growth native evergreen forest (Aetoxicon punctatum, Laureliopsis philippiana and Eucriphya cordifolia), and EP, covered with 4 and 16-year-old Eucalyptus nitens stands. Our results show that precipitation, stream and soil solution plot approximately along the LMWL, while xylem waters from all studied tree species plot below the LMWL, supporting the TWW hypothesis. However, we also found evidence of ecohydrological connectivity during the wet season, likely controlled by the amount of antecedent precipitation. These observations hold for all investigated tree species. On both sites, a different precipitation source for stream and xylem water was observed. However, in EP, bulk soil showed a similar precipitation source as xylem water from both E. nitens stands. This suggests that E. nitens may use water that is recharging the bulk soil compartment. We conclude that under a rainy temperate climate, the TWW hypothesis is temporal and does not apply during wet seasons.
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Papers by Niko Verhoest