GeoNet has recorded 27 aftershocks in the hours of darkness after yesterday’s “severe” magnitude 5.9 earthquake near Pōrangahau.
From 6pm Wednesday to 8am Thursday, aftershocks ranged from magnitude 2.1 to magnitude 4.2. The average depth of the shakes stayed around 14km.
They were all predominantly located within 5km of Pōrangahau, in a similar area where the original quakes struck.
GeoNet classed most of them as “weak” and “light”, with two at 6.01pm and 8.54pm reaching the “moderate” threshold (4.2 and 3.9 magnitude respectively).
Yesterday’s first quake struck at a depth of 21km at 10.16am. This was soon followed by a magnitude 5.4 quake at a depth of 17km a few minutes later in the same place and then another 38 aftershocks within three hours.