Kingy said:
https://www.abc.net.au/news/2022-08-04/iceland-volcano-fagradalsfjall-erupts/101302732
Visitors to a volcano in south-west Iceland have described being “mesmerised” by “dancing flames” as it began erupting on Wednesday.
Key points:
The volcano is around 32 kilometres from Iceland’s capital Reykjavik
There were a series of earthquakes close to the Earth’s surface in the past week
A spectator said the eruption was “five to 10 times bigger” than the previous one
The eruption came just eight months after the Fagradalsfjall volcano’s last blast officially ended.
Despite warnings from the Icelandic Meteorological Office urging people not to go near the site, many still gathered to watch the dramatic natural spectacle unfold.
“It’s just crazy,” Icelandic photographer Gunnar Freyr said after coming to watch the eruption.
“I thought the eruption was going to happen maybe like in a few weeks, and now it’s here and it is so beautiful.”
Watch this space. This is where continental plates are separating, and there is a fair chance that this may just be the start of a new series of eruptions.
Of course, it may not. IDK.
Does anyone know how many cubic metres of lava come out in a typical year in Iceland?
(Checks web, https://iris.unito.it/bitstream/2318/1701175/1/Copolla%20et%20al%202019_Annals.pdf)
I’m asking because Iceland began just 2 million years ago, at a depth of 1 km below sea level, has a peak altitude of 1.5 km and is, undersea, an oval of 770 by 500 km. That gives it a volume of 770*500*2.5*(1/3)*(pi/4) = 252,000 cubic km.
If that was a uniform lava flow rate over 2 million years then the average would be 0.126 cubic km of new lava per year. A cubic km is 10^9 is a billion cubic metres. The average is 126 million cubic metres per year.
Now I’m guessing that the current Iceland lava flow is very much smaller than that.
From linked report,1.5 ± 0.1 cubic km of lava was generated in the case of the 2014-2015 eruption at Holuhraun (Iceland). Over 6 months. That makes 3 cubic km per year, when an eruption is happening.
So I’m wrong, because 3 cubic km per year >> 0.126 cubic km per year. Or to put it another way, for the average rate of lava flow over the past 2 million years to be maintained, we would see an eruption like that of the 2014-2015 eruption on average every 24 years. And eruptions seem to happen more often than that.
Interesting.