Penyusunan Peta Kerentanan Gempa Di Berbah Kabupaten Sleman Menggunakan Metode Horizontal To Vertical Spectral Ratio (HVSR) Berdasarkan Pengukuran Mikrotremor Di Lapangan

Abstract

One of the major earthquake disasters that shook the Indonesian region was the 27 May 2006 earthquake, DI Yogyakarta. Kapanewon Berbah is the area with the most severe damage and casualties that occurred in Sleman Regency which was caused by the Yogyakarta earthquake in 2006. This damage was caused by several factors, including the magnitude, depth of the earthquake, distance to the hypocenter of the earthquake, duration of the vibration, condition of the soil and buildings, and local geological conditions and because Kapanewon Berbah is passed by an opak fault. Microtremor data measurements were carried out at Kapanewon Berbah to determine earthquake parameter factors such as Maximum Amplification (Ag), Dominant Frequency (Fg), Dominant Period (Tg), Earthquake Susceptibility Index (Kg), and Peak Ground Acceleration (PGA). This research was conducted at 36 points spread throughout the Kapanewon Berbah area with the help of Lunitek Digital Seismic Sensors. After collecting data in the field, the next step is data processing to obtain the desired earthquake parameters. The analysis used in calculating these parameters is using the Kanai Empirical method and using the Yogyakarta earthquake reference in 2006. The results obtained from this study were Ag values ranging from 1,621 – 15,810, Fg values ranging from 0,443 – 3,523, Tg values ranging from 0,284 – 2,259, Kg values ranging from 1,860 – 564,634, and PGA (gal) values ranging from 290,049 – 830,451.