INTEGRATION OF GEOPHYSICAL PARAMETERS ANALYSIS IN THEEARTHQUAKE PREDICTABILITY

INTEGRATION OF GEOPHYSICAL PARAMETERS ANALYSIS IN THEEARTHQUAKE PREDICTABILITY

Boko Nurdiyanto, Hendri Subakti, I Putu Pudja

Research and Development Center, Indonesia Meteorological Climatological and Geophysical  Agency (BMKG), Indonesia, boko.nurdiyanto@gmail.com

The purpose of this study is to analyze the predictability of earthquakes within ashort-term and mid-term scale in the western part of Java using various parameters, i.eseismicity, magnetic, electromagnetic, surface temperature, and humidity. In this research weuse the USGS and BMKG seismic data catalogue from 1973 to 2010, the earth's surfacemagnetic and electromagnetic field measurements data from magnetometer andmagnetotelluric observation station of BMKG at Pelabuhan Ratu, and the surfacetemperature and humidity data obtained from the Sukabumi AWS station of BMKG islocated in Pelabuhan Ratu. The case study used was large earthquake event with a radius of 300 km from Pelabuhan Ratu observation station that are on September 2^nd , 2009 (M7.5),September 13^th , 2009 (M6.6), October 16^th, 2009 (M6.4), November 18^th, 2009 (M5.3), January 10^th, 2010 (M5.3), February 20^th, 2010 (M5.0), May 18^th, 2010 (M6.0) and June 26^th,2010 (M6.3). From the seismicity data, seismicity anomalies was found in 2.5 - 3.5 years before earthquakes occur that are classified as mid-term precursor.  Anomalous magneticfield of the magnetometer was found 2-22 days before the earthquake occurs, magnetic fieldsfrom magnetotelluric anomalies was found 2-20 days before earthquakes occur, while theanomalous variation of surface temperature and average daily humidity was found 10 and 17days before earthquakes occur. Anomalous magnetic field, electromagnetic, variations insurface temperature and average daily humidity is classified as a short-term precursor. And periodicity in the Java subduction zone with magnitude M6 based on the depth of the sourceshowed a similar periodicity of dominant earthquake that is about four to five years.

Key words : Predictability, earthquake, precursor, seismicity, magnetic,temperature, humidity.

Catatan : Paper lengkap dipresentasikan pada Kongres : “Natural Cataclysms and Global Problems of the ModernCivilization”. Istanbul, 19-21 September, 2011.

Posted in: Geofisika