Seismicity in the Hellenic Volcanic Arc hydrothermal system in relation togeochemical parameters

The aim of the paper is to study the microseismicity of the island of Miles , Greece, in order to relate the recorded earthquake signals to venting per iodicity and to understand better the role of episodic events. A seismic ne twork of five three-component, triggering mode digital stations, installed on the island in the summer of 1996, recorded almost 400 local microearthqu akes and 500 signals, tentatively associated with hydrothermal activity. Th e analysis indicates low seismicity, probably associated with the existing hydrothermal field of the area. The hydrothermal signals are of two types, with peak frequencies of 2-3 Hz and 20-30 Hz, respectively. Preliminary ana lysis of records from the same experiment in 1997 showed that a high concen tration of seawater in particulates Mn was followed by a group of microeart hquakes 6-8 hours later. (C) 2000 Elsevier Science Ltd. All rights reserved .