Geochemistry of hydrothermally influenced sediments off Methana (western Hellenic volcanic arc)

• Published in: Chemie der Erde Vol. 64; no. 1; pp. 75 - 94
• Main Authors: Hübner, Andreas, Rahders, Erio, Rahner, Susanne, Halbach, Peter, Varnavas, Soteris P.
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 2004
• Subjects: Aegean Sea; Hydrothermalism; Marine; Methana; Sediment geochemistry; MED, Greece; Aegean Sea; Sediment geochemistry; Methana; Hydrothermalism
• ISSN: 0009-2819; 1611-5864
• DOI: 10.1016/j.chemer.2003.10.001

Surface sediment samples from near-shore shallow water as well as deeper water locations N and NE of the island of Methana were investigated geochemically. Shallow water samples from Thiafi Bay reveal up to 38-fold enrichment of As, associated with elevated contents of Sb, Fe and Zn. Deeper water samples NE of Methana show moderate Mn enrichment accompanied with elevated trace metal concentrations of As and, in some samples, Cd and Cu. In an area, where small mounds of possible hydrothermal origin were observed on the sea floor, fine-grained Fe-rich sediment was sampled with enrichment of typical hydrothermal trace elements As, P and Sb. Element enrichment in the investigated areas off Methana corresponds in terms of absolute concentrations and element suite to comparable hydrothermally influenced sediments from other locations of the Hellenic volcanic arc. The region between Methana peninsula and Aegina Island is not marked by vigorous hydrothermal activity, but localised enrichments of Fe and/or Mn, As, Sb as well as associated trace elements typically found in hydrothermally influenced sediments were identified.