Ok 3 places I am glad I am not tonight, Turkey, Indonesia and New Zealand. It’s cold in the eastern mountains of Turkey at night and there are still people there sheltering in tents and they are having more aftershocks still. Indonesia because they keep getting quakes and always will, at least until Australia smashed them into China.
New Zealand is where I am watching closely for the next few weeks and maybe a month or so. Why? Because the string of quakes on the Kermadec trench are creeping closer and closer. The fault system that runs through the islands of new Zealand starts at Tonga. The Pacific is trying to push west while the Indo-Australian plate pushes north. On the boundary between them from Tonga down to almost New Zealand is comprised of two very deep subduction trenches.
Along this line cascading series of quakes run south with most of them stopping short at the south end of the kermadec trench, but a few have had the right conditions of stress build up and timing to push beyond the end of the trench. One has been pushing slowly south all year and how is only just off-shore of the north island.
Now this was a 6.0, but not just a 6.0, but a 3, 5 to 6 magnitude quakes, building in strength and power over a few hours and relieving stress at that point of the fault but also allowing that stress to build on the fault south of it. And with earthquakes of less power causing considerable damage in Christchurch last February a 6 would be rather bad.
The other interesting quake today was the one in Washington State. An interesting quake that shows the building of the mountains is not over but not a precursor to a Cascadia quake, wrong fault line and this is a crustal quake in the mountains, not a subduction quake on the Cascadia fault because it’s to shallow there to be related to the subduction zone. While this an indicator that the stress on Cascadia is building, that is after all the reason the mountains are there, it is not useful for predicting anything on the other side of the mountain range.
- Earthquake off of North New Zealand (echlinm.wordpress.com)
- Focus on the Kermadec Trench (echlinm.wordpress.com)