article_snippet.sent: Using data from 2008, a French team found that ocean waves colliding generate seismic activity, but ocean waves only take 13 seconds or less to complete a single oscillation.
article_snippet.sent: ocean waves didn't explain why slow seismic waves - which provide the most powerful bell-like ringing - can last for longer than 50 seconds.
article_snippet.sent: Using seismic readings from 2008, a French team spotted that ocean waves colliding generate seismic activity, but these waves only take 13 seconds to complete a single oscillation.
article_snippet.sent: these waves didn't explain why slow seismic waves - which provide the most powerful bell-like ringing - can last for longer than 50 seconds . 'the largest hum   contains periods longer than 30 seconds, and the primary and secondary peaks are centered around 15 and five seconds respectively.'
article_snippet.sent: Using the 2008 data, Mr Ardhuin and Mr Ardhuin spotted that ocean waves colliding generate seismic activity, but these waves only take 13 seconds or less to complete a single oscillation.
article_snippet.sent: They didn't explain why slow seismic waves - which provide the most powerful bell-like ringing - can last for longer than 50 seconds.