Characteristics and geo-engineering aspects of the 2003 Bingöl (Turkey) earthquake

An earthquake (Mw = 6.4) occurred on May 1, 2003 in Bingöl province of the East Anadolu Region of Turkey. It was characterized by a shallow focal depth, an intense and prolonged aftershock activity and serious ground effects. This study presents main characteristics and geo-engineering evaluation of the earthquake based on site observations, strong ground motion records and geotechnical data. Although the earthquake caused rock falls and several landslides, and limited number of liquefaction-induced ground failures, no evident surface rupture occurred. However, site observations and distribution trend of the epicenters of the aftershocks suggested that the Sudügünü fault, which is a right-lateral strike slip fault striking in NW-SE direction, was the most probable causative fault. Based on the acceleration response spectra and natural periods of the structures in Turkey, it is concluded that the buildings with three to four stories in Bingöl should have been subjected to severe shaking. Amplification at the cliff sides due to topographical effects played an important role on structural damages. Since the limited number of liquefaction-induced ground failures occurred in rural areas, they did not cause any structural damage. However, one of these is a great of interest, because it occurred in soils, which resulted from weathered tuffs and its analysis also provided useful information about the horizontal ground acceleration necessary to initiate the liquefaction.