We perform the inversion using teleseismic events only for comparison. The stations and picks are identical to the data for teleseismic earthquake in this attempt.
Eighteen stations are used, divided into 11 in central Auckland, and 7 surrounding the former array. Low resolution channels are removed.
There are 121 events considered, though 13 are discarded due to bad data. We also have issue with the time window while we were picking.
The inversion shows negative velocity anomaly in most area in the Northland. The negative velocity in the North is a feature of our joint inversion.
There isn’t any change in travel-time residual distribution between initial and final model. The distribution is centred more in the positive direction which explains the mainly negative velocity anomaly.