The 8 June 2008 M w 6.4 Achaia–Elia, Greece Earthquake: Source Characteristics, Ground Motions, and Ground Failure Basil Margaris, a) George Athanasopoulos, b) George Mylonakis, b) M.EERI, Christos Papaioannou, a) M.EERI, Nikolaos Klimis, c) Nikolaos Theodulidis, a) Alexandros Savvaidis, a) Vicky Efthymiadou, b) and Jonathan P. Stewart, d) M.EERI The M w 6.4 Achaia–Elia (Greece) earthquake on 8 June 2008 was a right- lateral strike-slip event on a nearly vertical faul. Moment tensor solutions coupled with geologic structure and aftershock distributions suggest a fault strike of approximately 210° on a previously unmapped fault. Rupture appears to have been concentrated over a 10–25 km depth range and did not break the surface. The northern rupture limit appears to correspond to a NW-striking normal fault near the Kato Achaia coastline. The mainshock was recorded by 27 accelerometers at distances from the surface projection of the fault ranging from approximately 15 to 350 km. The data demonstrate faster distance attenuation than predicted by contemporary Greek ground motion prediction equations (GMPEs). On the other hand, an NGA GMPE generally captures the distance attenuation but shows underprediction bias at short and long periods. Despite the presence of a range of site conditions at recording stations in the city of Patras, we find no obvious effect of sediment depth on response spectra. We show the possible presence of rupture directivity at the north end of this bilateral rupture, but no apparent effect at the southern end. We described several relatively well-documented incidents of nonground failure and ground failure associated with liquefaction/lateral spreading and landslides. DOI: 10.1193/1.3353626 INTRODUCTION The Achaia–Elia (Greece) Earthquake occurred on 8 June 2008 at 12:25 UTC time. Strong shaking of sufficient amplitude to damage structures occurred over a broad area of approximately 2000 km 2 . The earthquake was reported to have been felt as far away as 350 km from the epicentral area. Within two days of the mainshock, a team of seismologists and engineers had mo- a) ITSAK—Institute of Engineering Seismology and Earthquake Engineering, Thessaloniki, Greece b) Department of Civil Engineering, University of Patras, Patras, Greece c) Department of Civil Engineering, Democritus University of Thrace, Xanthi, Greece d) Civil & Environmental Engineering Dept., University of California, Los Angeles, 5731 Boelter Hall, Los Angeles, CA 90095-1593; jstewart@seas.ucla.edu (corresponding author) 399 Earthquake Spectra, Volume 26, No. 2, pages 399–424, May 2010; © 2010, Earthquake Engineering Research Institute