General observations of effects of the 30th September 2009 Padang earthquake, Indonesia

Abstract

The Mw 7.5 Padang earthquake struck at 17:16 local time on 30th September 2009 with an epicentre offshore about 60 km west-northwest of Padang, capital of West Sumatra Province. More than 1,100 people were killed, and over 2,900 injured. The earthquake caused significant damage to public buildings and offices as well as to about 140,000 houses. It affected 250,000 families through the total or partial loss of their homes and livelihoods. More than half the earthquake fatalities occurred when several villages inland from Pariaman were buried by landslides. However, the damage and destruction of building structures was a major cause behind human and property losses. In addition to landslides, the earthquake triggered extensive liquefaction and lateral spreading in the region. A ten-member team from New Zealand visited the area under the auspices of NZAid and New Zealand Society for Earthquake Engineering to undertake building safety evaluations. The team spent most of their time in Padang city and other nearby earthquake-affected areas. This paper presents their observations and explores causes behind the damage and destruction of buildings by the moderate to strong earthquake shaking.