Auckland Volcanic Field & Hauraki Rift Seismic Experiment

May-June 2023

Hello friends 🌋 We're former Aucklanders visiting home to conduct a short study of two poorly-understood geological features: The Auckland Volcanic Field (consisting of 53 known volcanoes), and the North-South trending Hauraki Rift (which is slowly widening, separating Coromandel from Auckland at a rate of 1 mm per year).

Our aim is to deploy ~50 small seismometers throughout the region for 30-40 days, recording the low frequency (< 1 Hz) vibrations generated by ocean waves and small earthquakes. Waveform data from a single site alone doesn't look like much (example below), but with a big enough network we can build up an image of the Earth’s structure. There are already long-term sensors scattered throughout the region, but we have a short opportunity to install a 'high-density array' to fill in the gaps. This may help us to understand:

  1. why recent volcanism is concentrated only at Auckland
  2. where the magma is coming from
  3. possible effects of the widening Hauraki Rift
  4. previously hidden active faults and seismic risk

example of seismic waveform

We've asked the citizens of Tāmaki Makaurau and beyond for help by lending a small, secure, and out-of-the-way spot in their paddock or yard to host a small sensor during May-June. The instrument doesn't emit any signals (radio, bluetooth, magnetic, wifi, etc) or interfere with the environment -- it only records pre-existing acoustic energy travelling through the earth.

**Updated 06/06/2023: There are now 58 sensors installed and recording! Sincere thanks for the generous support 🌋!

[map above shows the general area of each installation]

This is an independent project, funded as part of post-doctoral research at the Australian National University's Research School of Earth Sciences. No part of this research is intended for resource exploration or mining (nor would it be useful for this purpose). Data and findings will be shared freely with fellow researchers in Aotearoa/New Zealand and Australia.

-RPC🎃 & KB🦇