Seismic quiescence has been proposed as a precursor to many large earthquakes. In this paper we present two cases in which precursory quiescence is interrupted several years prior to great earthquakes by triggered events in the upcoming rupture areas. This triggering results in complex precursory patterns which include seismic quiescence and triggered events. Prior to the Kermadec earthquake of 1976 (Ms= 8.0) events in the rupture zone were triggered by a quake on the outer rise and one near the future mainshock epicenter. Events were triggered by an earthquake on an adjacent segment of the plate interface and by one near the epicenter of the New Hebrides earthquake of 1980 (Ms= 8.0). We propose that two preconditions must be fulfilled for triggering to occur. First the stress in the region must be close to the failure stress and second nearby events must occur which are large enough to affect the stress field but not large enough to cause an immediate mainshock.
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