PEMETAAN MIKROZONASI AREA SUMUR MINYAK TUA DESA BENDOHARJO, GROBOGAN, JAWA TENGAH BERDASARKAN PENGUKURAN MIKROSEISMIK; MICROZONATION MAPPING OF AN OLD WELL AREA IN BENDOHARJO, GROBOGAN, CENTRAL JAVA USING MICROSEISMIC METHOD

ANNISA FITRI, Imam Suyanto

2015 | Skripsi | FMIPA

Geophysical study by applying microseismic method has been conducted in order to generate a microzonation map, consisting the dynamic soil and rock propeties such as resonant frequency and amplification factor in an old-well area in Bendoharjo, Gabus, Grobogan, Central Java, using one short period seismometer Lennartz 3D Lite with 80 Hz sampling frequency. The research area covers a grid of 2 x 3.5 km with 40 measurement points. Processed data from GEOPSY by applying HVSR (Horizontal to Vertical Spectrum Ratio) method shown that resonant frequency ranges from 3 – 23 Hz with amplification factor 0.83 – 5.6. Thickness of weathered soil ranges from 3 – 30 m. Seismic susceptibility index ranges from 0.1 – 2.9. And peak ground activity ranges from 8 – 23 gal.

Kata Kunci : microseismic; HVSR; seismic susceptibility index; peak ground activity.