ANALISIS ENERGI KUMULATIF GEMPA GUNUNGAPI MERAPI BERDASARKAN DATA REAL-TIME SEISMIC AMPLITUDE MEASUREMENT (RSAM) DAN PERBANDINGANNYA TERHADAP DATA SEISMIK PERIODE MEI-JUNI 2006ud

摘要

Merapi volcano is located in coordinates 7°32,5' S - 110°26,5' E in twoudprovinces between Yogyakarta and Central of Java. Analysis of activities ofudMerapi volcano has been done about its cumulative energy in May 8 thru June ofud7, 2006 using digital and seismic analog data. Analysis and experiment has beenuddone by collecting the data of volcanic activity in the time of seismic crisis 2006.udData which used to determine the cumulative energy of Merapi volcano and showudthe increasing energy which follow the vulcanic activity eruptions on June of 14,ud2006.udThe Real-time Seismic Amplitude Measurement (RSAM) technique is audsystematic electronic and computer method that provides a continuousudmeasurement of average absolute seismic amplitudes for any number of seismicudstations desired. The limitation of this method are can not discriminate betweenudtypes of volcanic earthquakes, teleseismic events, regional earthquakes, wind, andudother noise.ududThe correlation of the graphic from both data is 0,94098. And show theudinformations about its spectral power that dominated in frequency of 1.3 Hz andudpredicted that volcanic swarm caused the pressure of the magmatic andudincreasing the number of LF (Low Frequency) earthquake. However, owing to theudrapid increase in cumulative RSAM counts, the data were used as a basis forudissuing warnings before the eruptions on June 14.ududududKeywords: volcanic earthquake, RSAM, cumulative energy, correlation.ud