Horizontal to Vertical Spectral Ratio (HVSR) Analysis of the Passive Seismic Data on Alluvial Lithology: An Example from Bandung Basin Rim

Bandung basin is surrounded by active volcanoes at the center of Western Java region. Soil type this area consists mostly volcanic alluvial, formed past activities. At location, we performed passive seismic surveys to reveal sedimentary characteristics using a triaxial seismometer, study properties which have potential implications on environmental aspects, such as natural disaster mitigation and city planning. In work reported analysis three component vibration signals means Horizontal Vertical Spectral Ratio (HVSR) calculation identify sediment thickness through dominant frequency earth vibration. The method signal processing successfully revealed amplification factor area, very important determine ground motion induced disasters. data was collected laboratory developed logging device with sensitivity 0.28 ± 5% V⋅s/cm. preconditioning carried out shape acquired high noise level, prior HVSR calculation. From measurements computation, obtained variation chosen survey around 32 64 meters, corresponding measured 2.5 5.0 Hz. results agree well reference microtremor surveys. frequencies are also consistent range suggested literature