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Hikurangi Subduction Earthquakes and Slip Behaviour

Diagnosing peril posed by the Hikurangi subduction zone: New Zealand’s largest plate boundary fault

2016 -2021
Funder: Endeavour Fund, Ministry of Business, Science, Innovation and Employment. 
Contact: Laura Wallace 

Hikurangi subduction zone

Between 2016-2021, a large team of national and international scientists will be studying the Hikurangi plate boundary to find out what risk it poses to New Zealand. The Hikurangi plate boundary, located off the East Coast of the North Island, is where the Pacific tectonic plate subducts (or dives underneath) the Australian tectonic plate - and is what scientists call a subduction zone. 

Subduction zones are a type of fault and are responsible for the largest and most powerful earthquakes and tsunamis in the world, such as Sumatra 2004, Chile 2010, and Japan 2011.

The Hikurangi subduction zone is potentially the largest source of earthquake and tsunami hazard in New Zealand, but there is still much to learn about it. 

We know that the Hikurangi subduction zone can produce large earthquakes and tsunamis, and that these events have occurred in the past. However, we don’t know how often these earthquakes tend to happen, nor do we know how large they can be. Understanding what hazard this poses for East Coast communities is a key outcome of this research project.

It is also the best place to study slow slip events (also referred to as “slow earthquakes” as they happen slowly over a period of weeks to months, rather than suddenly in one large earthquake). The world’s shallowest slow slip events occur just offshore Gisborne, and offer a globally unique opportunity to understand why slow slip events happen.

The project involves scientists from GNS Science, NIWA, Victoria University of Wellington, Massey University, University of Auckland, University of Otago, the University of Canterbury as well as overseas researchers.

These short information sheets explain the project and the tools we are using in more detail:

1. Hikurangi Project overview: To read about the project's aims and methods, download this information sheet: FactSheets_general.pdf (247.12 kB)

2. The 2017-2018 IODP Drilling programme: to better understand the Hikurangi Subduction Zone, download this fact sheet about IODP Drilling IODP_FactSheets_drilling.pdf (268.15 kB)  (IODP is the International Ocean Discovery Programme)

3. The Seismic Surveying programme: to read about how we get detailed sub-seafloor images of the Hikurangi Subduction Zone, download this fact sheet FactSheets_seismic.pdf (367.61 kB)

Watch a short video about NZ's largest fault below.