Earthquake vulnerability assessment using RS and GIS :: Case study Bantul earthquake Bantul Regency Yogyakarta

SEPTERIANSYAH, Iwan Mulia, Dr. Junun Sartohadi, M.Sc

2010 | Tesis | S2 Geo Informasi untuk Manajemen Bencana

An earthquake is a sudden motion or trembling of the earth caused by a release of strain accumulated within or along the edge of Earth's tectonic plates. Earthquake that occurred on May 27, 2006 in the Special Region of Yogyakarta Provinces and Central Java earthquake caused more than 5700 people died, 37,927 people injured, and 240,396 homes destroyed and make a disruption to local economic activities. Assessment of damage and losses indicating the damage and losses worth of Rp 29.1 trillion (US $ 3.1 million), making Bantul earthquake as one of the worst disaster in Indonesia and the world in the last 10 years. This study focused on the relationship between lithology arrangement, geomorphology, and level of damage caused by May 2006 Bantul earthquake. The methodology used in this study is compare lithology from borehole interpolation, geomorphology elements, and IKONOS imageries of Bantul earthquake actual damage. The results show that high vulnerable areas have 7-15 m of groundwater level, distance from fault <500 m, composed of Alluvium and Young Merapi Deposits, and consists of loose rocks (gravel, sand, silt, and clay), lahar breccia, tuff, breccia, agglomerate, and volcanic ash. Medium vulnerable areas have 7-15 m of groundwater level, distance from fault 500-1000 m, composed of Young Merapi Deposits, and consist of lahar breccia, tuff, breccia, agglomerate, and volcanic ash. Low vulnerable areas have non aquifer, distance from fault >1000 m, composed of Sentolo, Wonosari, Sambipitu, Nglanggran, Semilir Formation, and consists of Volcanic breccia, agglomerate, lava, tuff, shale, siltstone, sandstone, conglomerate, limestone, and calcarenite.

Kata Kunci : Gempabumi,Gempabumi Bantul,Susunan litologi,Geomorfologi,Tingkat kerusakan gempabumi,earthquake, Bantul earthquake, lithology arrangement, geomorphology, earthquake damage level, earthquake vulnerability