UPAYA MITIGASI BENCANA GEMPABUMI TEKTONIK DI WILAYAH JAWA TIMUR DENGAN MENGGUNAKAN PSHA (PROBABILISTIC SEISMIC HAZARD ANALYSIS); MITIGATION OF TECTONIC EARTHQUAKE DISASTER FOR EAST JAVA REGION USING PSHA (PROBABILISTIC SEISMIC HAZARD ANALYSIS)

Kumala, Siti Ayu, N

2016 | Disertasi | FMIPA

Many research on the forecast of seismic hazards in Indonesia have done, but detail analysis of each region needs further assessment. East Java is an area with high earthquakes Frequency. Therefore, the analysis of seismic hazard in East Java in detail is necessary as a first step in disaster mitigation. This research aims to make hazard map for for 10% and 2% PE in 50 years (return period of 500 years and 2500 years) as mitigation of tectonic earthquake disaster in East Java region. The PSHA 2007 from USGS (United State Geological Survey) is a software that was used in this analysis process. Data of the earthquake catalog used in this analysis is the historical events earthquake from 1900 to 2015, with area 109oBT - 116oBT and 6oLS - 12oLS, taken from USGS, ISC, ANSS and BMKG. Parameters of focal mechanism from 1976 to 2015 are taken from GCMT and parameter of faults and subduction obtained from previous research. The result of this calculated obtained distribution hazard value in PGA condition (T = 0 second) for 10% and 2% PE in 50 years (return period of 500 years and 2500 years) in bedrock are 0,2 g – 0,4 g and 0,45 g – 0,65 g. While for hazard value in bedrock in spectral condition 5 hz (T = 0,2 second) for 10% and 2% PE in 50 years are 0,45 g – 0,85 g and 0,65 g – 1,25 g. For hazard value on bedrock in spectral condition 1 hz (T = 1,0 second) for 10% and 2% PE in 50 years are 0,1 g – 0,27 g and 0,2 g – 0,4 g. This result is higher than result from Revison of Earthquake Maps of Indonesia SNI-03-1726-02 (2010) and show that East Java is including area with determine middle to high seismic hazard.

Kata Kunci : Seismic Hazard Analysis; PSHA; PGA; Spectral Acceleration.