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Deformation along the subduction zones are continuous processes in a geological time scale. At shorter time scales, this continuous process is fragmented through discrete events such as individual earthquakes. A snapshot of the subduction zone process along the Kurile-arc has recently been delineated by the occurrence of two large earthquakes in Nov.15, 2006 (M=8.3) and Jan.13, 2007 (M=8.2). The first one occurred along the plate interface as a pure thrust earthquake and the second one was a pure normal earthquake which occurred on the outer rise, within the down-going lithospheric slab. The processes leading to these earthquakes are visible on both the bathymetry and the gravity anomalies of the trench. Trench parallel topography (TPTA) and gravity (TPGA) anomalies are investigated in the light of the recent earthquakes. The slip inversion based on teleseismic data shows clear correlations between the high slip patches (asperities) and the TPGA when the effect of the topography is removed. In addition, the distribution the foreshocks and aftershocks seem to be controlled by the location of the major asperities along the fault planes for both earthquakes. The spatial and temporal analysis of the instrumental seismicity along the entire Kurile-arc reveals that there are significant gaps close to the 2006 and 2007 earthquakes, especially in the Northeast direction. The location of the major asperities seem to have a major role in determining the spatial distribution of the large earthquakes along the arc, however, the size of the individual earthquakes seem to be more dependent on the occurrence of the last large earthquake on adjacent segments of the subduction and their interaction. Furthermore the origin of the asperities is probably related to the location of the sea-mounts.
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