This research has been carried out aiming to classify earthquakes at Lokon Volcano and analyze the character of the earthquakes to determine the mechanism of the eruption of Lokon Volcano is based on the data recorded seismograms April to May 2012. The stages in analyzing the characteristics of the earthquake is the waveform analysis and spectral analysis . On waveform analysis aims to determine the P wave comes time ( Tp ) and S waves ( Ts ) and the duration of the earthquake . While spectral analysis aimed to determine the frequency of these earthquakes . The second stage of the obtained classification of volcanic earthquakes in the earthquakes, shallow volcanic earthquakes, earthquake monochromatic, and tectonic earthquake. Shallow volcanic earthquakes located at depths of 0.5 to -1.5 km , duration range from 3 to 16 seconds with a frequency range from 4 Hz to 18 Hz . Volcanic earthquakes located at depths -6 km to -1,duration range from 6 to 20 seconds with a frequency range from 6 Hz to 13 Hz . Earthquake discovered long period is two monochromatic low frequency earthquakes at depths of up to -1.5 -2 km which has two peaks in each of the station frequency is the frequency of the dominant and sub - dominant . Dominant frequency of the seismic monochromatic range 2.88 Hz to 4.88 Hz and sub -dominant frequency range from 5.04 Hz to 8.7 Hz . Duration of tectonic earthquakes about 50 until 470 seconds with a frequency range from 1 to 6 Hz. Volcanic earthquakes and monochromatic associated with normal faulting .Increased seismic activity indicates impending eruption
