Auckland was built on top of an active — in geologic terms — volcanic field: The Auckland Volcanic Field (AVF). As a result, GeoNet has instrumented the area with a regional network of seismometers.

mapAK

Map of the seismic stations that make up the AK network from GeoNet.

Seismologists monitor the AVF with this network, while DEVORA (Determining Volcanic Risk in Auckland) studies the geologic (including seismic) hazard and risk associated with the volcanic field.

Seismic activity in the area is actually relatively low, but recent advances in seismology use the noise of the city and the surrounding oceans to extract information between seismic stations as if one of the seismic stations were the source (the “earthquake”) and the other the recorder. To do this properly for the AVF, we first need to determine the orientation of each seismic station.