Technotronic, Volcanics, and related Geology

[kladner]

Originally Posted by Dr Sardonicus

Magnitude 8 earthquake strikes Amazon jungle in Peru

I hope the initial low casualty reports don't increase too dramatically.

[kladner]

Originally Posted by xilman

When a glacier drops its stuff,
Whether granite or tuff,
That's a moraine.

Scusa me, but you see this is not Napoli.....

[ewmayer]

Originally Posted by xilman

When a glacier drops its stuff,
Whether granite or tuff,
That's a moraine.

Gneiss!

[kladner]

https://www.volcanocafe.org/white-island/
White Island, in the Bay of Plenty, New Zealand, is the volcano which recently killed some tourists, likely with a steam explosion. The article mentions that the edifice itself is water saturated. Its magma is also very wet and gassy: perfect for explosive eruptions.

The Bay of Plenty is an evocative name. The Bay is sandwiched between the two northerly peninsulas of The North Island. The name includes the adjacent land region, so this is a Bay you can live in. The geyser of Rotorua is world-renowned. So are the adjacent Taupo volcanoes, although not quite as widely publicised. Too many of the Earth’s largest volcanic eruptions of the past million years have come from here, the most recent one around 100 AD. Since humanity arrived here there has been one notably eruption. The region is quiet now without any sign of impending activity. GPS measurements show deflation across the region which is a positive sign for those who like their volcanoes scenically quiet.

[kladner]

I posted this photo in the Catastrophic Earthquake thread, but want to have it here as well.

Necro-edit: This is the inner crater of Taal Volcano, Philippines, circa 2013. The caldera lake is in the distance.

[Nick]

If you do come to Europe at some point, consider visiting Santorini

Ships sail into the flooded caldera through one of the gaps in the ring,
and you can go ashore and climb the steps up to the town of Thera with stunning views.
There are currently no signs of volcanic activity above the water, but the Minoan eruption
(about 3600 years ago) was possibly the largest ever recorded.
A cruise ship also sank here in 2007 and has never been recovered.
The water is very deep even close to the shore as the sides of the volcano are steep.

[kladner]

Originally Posted by Nick

If you do come to Europe at some point, consider visiting Santorini
Attachment 21643
Ships sail into the flooded caldera through one of the gaps in the ring,
and you can go ashore and climb the steps up to the town of Thera with stunning views.
There are currently no signs of volcanic activity above the water, but the Minoan eruption
(about 3600 years ago) was possibly the largest ever recorded.
A cruise ship also sank here in 2007 and has never been recovered.
The water is very deep even close to the shore as the sides of the volcano are steep.

Santorini is one of those must-see places for the volcano-obsessed. I can only wish. I have never been across the Atlantic.

[ewmayer]

Scientists discover 91 volcanoes below Antarctic ice sheet | The Guardian: This is in addition to 47 already known about and eruption would melt more ice in region affected by climate change.

In addition to the news of the new volcano cluster, highlights an interesting connection between global warming and increasing volcanism:

Scientists have uncovered the largest volcanic region on Earth – two kilometres below the surface of the vast ice sheet that covers west Antarctica.

The project, by Edinburgh University researchers, has revealed almost 100 volcanoes – with the highest as tall as the Eiger, which stands at almost 4,000 metres in Switzerland.

Geologists say this huge region is likely to dwarf that of east Africa’s volcanic ridge, currently rated the densest concentration of volcanoes in the world.

And the activity of this range could have worrying consequences, they have warned. “If one of these volcanoes were to erupt it could further destabilise west Antarctica’s ice sheets,” said glacier expert Robert Bingham, one of the paper’s authors. “Anything that causes the melting of ice – which an eruption certainly would – is likely to speed up the flow of ice into the sea.

“The big question is: how active are these volcanoes? That is something we need to determine as quickly as possible.”
...
However, he pointed to one alarming trend: “The most volcanism that is going in the world at present is in regions that have only recently lost their glacier covering – after the end of the last ice age. These places include Iceland and Alaska.

“Theory suggests that this is occurring because, without ice sheets on top of them, there is a release of pressure on the regions’ volcanoes and they become more active.”

[Uncwilly]

Originally Posted by ewmayer

In addition to the news of the new volcano cluster, highlights an interesting connection between global warming and increasing volcanism:

And when the overburden of ice is lessened, there is a chance that the weight "cap" on the other volcanoes will come off and pop pop pop.

[kladner]

Originally Posted by Uncwilly

And when the overburden of ice is lessened, there is a chance that the weight "cap" on the other volcanoes will come off and pop pop pop.

I can see how rebound could set off a lot of stuff, especially in volcanic-inclined zones.
EDIT: Trading ice for fire.

[kladner]

The Mt Saint Helens catastrophic eruption was 40 years ago, today.