<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">A. Kolaitis</style></author><author><style face="normal" font="default" size="100%">Papadimitriou, P.</style></author><author><style face="normal" font="default" size="100%">Kassaras, I.</style></author><author><style face="normal" font="default" size="100%">Makropoulos, K.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Seismic Observations with broadband instruments at Thira Volcano (Greece)</style></title><secondary-title><style face="normal" font="default" size="100%">Bulletin of the Geological Society of Greece</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://ejournals.epublishing.ekt.gr/index.php/geosociety/article/view/16844</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">XXXX</style></volume><pages><style face="normal" font="default" size="100%">1250-1261</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;em&gt;Two arrays equipped with broadband sensors were installed for a period of 10 months, in order to study the seismic activity in the area of Santorini (Thira) volcano. During these periods, about 330 earthquakes were recorded and located within a radius of 50 km from the center of the caldera. An iterative damped traveltime inversion procedure yielded a local 1-D&amp;nbsp;&lt;/em&gt;&lt;em&gt;Ρ&lt;/em&gt;&lt;em&gt;-wave velocity model and improved locations with an accuracy better than 5 Km in both horizontal and vertical components for 135 earthquakes. Those are mainly distributed within a depth range 5-18 Km, in the vicinity of the submarine Kolumbo Reef (NE of Santorini Island). Signal analysis of the recorded volcanic earthquakes including typical Fourier transformations and several operations in the time-frequency domain, allowed their dominant frequency determination and their classification into three groups based on waveform appearance and frequency content: (1) highfrequency events; (2) low-frequency events; and (3) volcanic tremor. Frequencytime analysis of tremor, detected at three stations, revealed two kinds of harmonic tremor with one sharp peak, at 3-5 Hz and 8.5-10 Hz.&lt;/em&gt;</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue></record></records></xml>