The GeoNet project,
which monitors quakes in New Zealand, recorded a Magnitude 5.4
Earthquake at a depth of 64 km, about beneath the South Taranaki Bight, between North and South islands, New Zealand, at about 11.45 pm New Zealand Daylight Time (about 10.45 am GMT) on Saturday 25 January 2020. There are no reports of any damage or casualties associated with this event, but it was felt by over 26 500 people from Christchurch up to Auckland, according to GeoNet.
The approximate location of the 25 January 2020 South Taranaki Bight Earthquake. USGS.
New
Zealand is located on the boundary beneath the Australian and Pacific
Plates. Beneath the islands the Pacific Plate is being subducted beneath
the Australian Plate. This causes a great deal of friction which causes
Earthquakes where the boundary between the two plates is close to the
surface; this is to the east of North Island, but onshore on South
Island, where it can lead to strong Earthquakes. Technically such quakes also occur where the
plate margin is deeper, but these are felt less strongly as the rocks
between the boundary and the surface absorb much of the energy, making
strong tremors much less frequent on North Island. As the Pacific Plate
sinks deeper into the Earth it is partially melted by the friction and
the heat of the planet's interior. Some of the melted material then
rises through the overlying Australian Plate, fuelling the volcanoes of
New Zealand.
The subduction zone beneath New Zealand, and how if fuels Earthquakes and volcanoes. Te Ara.
Witness
reports of Earthquakes can help scientists to understand these events,
and the underlying geologic processes that cause them. If you felt
either of these quakes then you can report it to the GeoNet here.
See also...
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