Map of the Southern Pacific Ocean Earthquakes
The USGS has up-to-date details on the March 4, 2021events.
A magnitude 8.1 earthquake near the Kermadec Trench was the third and largest earthquake of the three. This event is near the magnitude 7.4 earthquake that occurred earlier this afternoon, some 600 miles (950 km) north of New Zealand. While large, these earthquakes are remote and the USGS PAGER report is Green for fatalities and economic losses. The M8.1 earthquake is about 11 times larger than the earlier M 7.4 and occurred at a shallower depth (early estimates about 12 miles, or 20 km). The larger size and shallower depth increase the tsunami potential, and NOAA have released tsunami warnings for many islands in the southwest Pacific. The National Emergency Management Agency of New Zealand have also released a tsunami warning.
Like the preceding M7.4, the M 8.1 earthquake occurred as the result of thrust faulting at shallow depth, likely on the subduction zone interface between the Pacific and Australia plates. Large earthquakes in this region are common. While the M 7.4 earthquake was unlikely to have been triggered by static stress changes caused by the prior M 7.3 near New Zealand this morning, the M 8.1 and M 7.4 are directly related. The M 7.4 event can be considered a foreshock of the M 8.1.
Further and updated information about the earthquake can be found here:
USGS scientists expect that these events will trigger aftershocks, but these will decrease in frequency over time.
If you felt the M7.3 earthquake, report your experience on the “USGS Did You Feel It?” website for this event.
For information about tsunami watches, warnings or advisories, visit the National Oceanic and Atmospheric Administration (NOAA) tsunami website.
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Learn more about the USGS Earthquake Hazards Program.
We will update this story if more information becomes available.
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- Did You Feel It?