15 M7.5+ earthquakes recorded near New Zealand since 1900
Earthquake Details
Magnitude: 6.5Mw
Event Time: 2014-03-26 03:29:36 UTC
Location: 26.092°S 179.279°E depth=493.1km (306.4mi)
Nearby Cities:
- 448km (278mi) NW of Raoul Island, New Zealand
- 786km (488mi) SW of Nuku`alofa, Tonga
- 884km (549mi) S of Suva, Fiji
Seismotectonics of the Eastern Margin of the Australia Plate
Excerpts from the Tectonic Summary [sourced from USGS]
Since 1900 there have been 15 M7.5+ earthquakes recorded near New Zealand. Nine of these, and the four largest, occurred along or near the Macquarie Ridge, including the 1989 M8.2 event on the ridge itself, and the 2004 M8.1 event 200 km to the west of the plate boundary, reflecting intraplate deformation. The largest recorded earthquake in New Zealand itself was the 1931 M7.8 Hawke’s Bay earthquake, which killed 256 people.
Large earthquakes are common along the North New Hebrides trench and have mechanisms associated with subduction tectonics, though occasional strike slip earthquakes occur near the subduction of the D’Entrecasteaux ridge. Within the subduction zone 34 M7.5+ earthquakes have been recorded since 1900. On October 7, 2009, a large interplate thrust fault earthquake (M7.6) in the northern North New Hebrides subduction zone was followed 15 minutes later by an even larger interplate event (M7.8) 60 km to the north. It is likely that the first event triggered the second of the so-called earthquake “doublet”.