Monday Musings: New Zealand (times two) and a Sinabung Update

Monday is here already and although lots of folks in the States have today off (Labor Day), I don’t (from blogging or teaching)!

Some news:

There is a whole lot more information out there on the Christchurch earthquake that occurred last Friday. It is remarkable that no one died due to the earthquake, especially considering how much surface shaking there must have been – you can see some of the evidence of that on an excellent New Zealand GeoNet page on the earthquake. There are also some great images of the so-called “sand volcanoes” related to liquifaction of the sandy sediment under parts of Christchurch and Canterbury. There have been quite a few aftershocks from the earthquake as well.

Speaking of New Zealand, I did run across an interesting article recently on inflation/deflation in the Auckland Volcanic Field. The city of Auckland sits on series of active volcanoes – mostly small scoria cones – some of which erupted as recently as 600 years ago. A paper in the Journal of Geophysical Research – Solid Earth – found evidence that some parts of the Auckland area are area of inflation and deflation (detected using inSAR imaging). However, this is believed to be due to water recharge and withdrawal under the area, but inSAR could be useful in seeing magmatically-driven uplift in the Auckland Volcanic Field when it starts getting ready to erupt again (and if you have been to the Auckland War Memorial Museum, you can experience what that eruption might be like).

Over in Indonesia, Sinabung continues showing signs of increasing unrest. It experienced its third set of explosions over the weekend and many evacuees continue to stay away from the volcano. The seismicity is still high under Sinabung. The evacuees were visited by the president of Indonesia Susilo Bambang Yudhoyono. I’m not too sure about his message: “Hopefully, the volcano will soon be back to normal so that all of you can safely return home again”, but I suppose he is a politician. However, he did offer more aid for the evacuees.

Finally, I saw a couple articles (french) on signs that Piton de la Fournaise (french) on Reunion Island might be heading towards new eruptions. The local authorities to preaching vigilance in case a new eruption does occur. The volcano on the French island produced a spectacular fissure eruption last November-December.

Top left: A view across Auckland over the top of Mt. Eden, part of the Auckland Volcanic Field.