Fig. 4From: Distribution of low-frequency earthquakes accompanying the very low frequency earthquakes along the Ryukyu TrenchSpectral amplitudes of various sources. Time window for each calculation was set to 400 s. Red lines show the low-frequency earthquakes (LFEs) and very low frequency earthquakes (VLFEs) that occurred during 12:00–13:00 on June 1, 2005 (UT). Black line shows the ordinary earthquake (magnitude 2.4), which occurred at 10:44 on May 27, 2005 (UT). Gray lines show the ambient noiseBack to article page