Bloody hell, if we could not?!

#quake #wobble #GeoNet

We were woken up this morning at 5:39 am by the the first #earthquake #eqnz I have felt in a long time. Magnitude 5.1 near Te Aroha, about 60 km from where I am as the tui flies. See the details on #Geonet here:
https://www.geonet.org.nz/earthquake/2023p007281
It was widely felt around the upper North Island with over 20000 felt reports.

By New Zealand standards this isn't a particularly tectonically active area, so it creates a bit of excitement. Today's earthquake was possibly due to movement on the Kerepehi Fault underneath the Hauraki Plains. Prehistoric movement on this fault has been studied (https://www.tandfonline.com/doi/full/10.1080/00288306.2015.1127826) to estimate recurrence and size of potential damaging earthquakes (<5ka and Mw 5.5 to 7.0, so today's earthquake was approaching estimates).

The danger in this part of NZ is a lot of older housing and infrastructure has little or no seismic design so even a 'moderate' earthquake could cause serious damage. And it could be the little things that cause major headaches. For instance, the house I am staying in was built in 1948 and the toilet is cemented into the downpipe. That fixed junction is a point of failure in serious shaking so a house may well survive an earthquake in good condition, but be unusable without a functioning toilet... (the building code since the 1970's specifies a flexible junction to avoid breakage). Fingers crossed that may be the last quake for a while!