Aotearoa Earthquake and Volcano Forecast Service

Fiordland-Pyke River Series. July-Sept 2026 16 July 2026 - 2 September 2026

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Migration paths are a common feature of quake series and the recent quake activity in Fiordland offers an excellent example.
Draw a line between the 16 July Fiordland 5.9 and the 2 September Pyke River 5.3, 5.2 double quakes.
This line parallels the great quake migration path across all New Zealand, the Hikurangi Fault.
The 12-13 August forecast period reflected this potential Hikurangi aligned migration pathway with Pyke River, Cascade River and South of Haast directly along that Hikurangi migration pathway. Those risk locations weren't randomly chosen.
Sadly spaceweather at the time faded out and all tectonic movement eased as the energy source dried up. No quakes and a failed forecast.
Weak spaceweather from 28 August has persisted for several days, right on the quake driving threshold of 400km/second with fluctuating magnetic orientation but often oriented southward and favourable for quakes.
Quake timing is very difficult to forecast under such weak but long lived geomagnetic quake driving conditions.
A tectonic release has eventually occurred on 2 September and exactly along the Hikurangi Fault orientation.
The 12-13 August Pyke River risk locations were justified but without timing accuracy, forecasts have limited value and a great day out for the sceptics.
The arrows drawn perpendicular to the migration line are the direction of movement of the Southeast Pacific Ridge from its source in the Southern Pacific Ocean as it subducts under Fiordland.
Quake migration is still possible from Pyke River into Lower Arawhata River during the next days or weeks with new spaceweather although Mag 4 seems more likely than Mag 5 as the migration weakens.