Before the Mid Niigata Prefecture earthquake in 2004 (Japan) , the chances of earthquakes triggering landslides in primary rock region and/or re-activating past landslides were regarded to be minimal in Japan. However in the events such as the Mid Niigata Prefecture earthquake in 2004 (Japan) , the Niigataken Chuetsu-oki earthquake in 2007 (Japan) , the Iwate-Miyagi Nairiku earthquake in 2008 (Japan) , the Chi-chi earthquake in 1999 (Taiwan) , the Northern Pakistan earthquake in 2005 (Pakistan) , a considerable number of seismogenic large-scale landslides occurred at their Tertiary sedimentary rock regions.
We describe in this paper the mass movement mechanism and development history of the large scale landslide that occurred at the time of the Iwate-Miyagi Nairiku earthqeake in 2008 based on the investigation by surface prospecting. In addition, we compare other Tertiary landslides induced by similarly large scale earthquakes to investigate the common occurrence factors found in their geological, topographical, slide surface and movement features.

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