Ice Cap Meltdown -> Land Upheaval -> Earthquakes?

  • Thread starter Thread starter dimensionless
  • Start date Start date
  • Tags Tags
    Ice
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
4 replies · 6K views
dimensionless
Messages
461
Reaction score
1
I've read that if and when the Antarctic icecap melts off, the land will rise up due to having a very massive amount of ice melt off. This sounds like it could effect the tectonic plates and the bedrock. Is this land upheaval apt to cause Earth quakes and maybe even volcanism?
 
Last edited:
Earth sciences news on Phys.org
It's called isostatic uplift/rebound, and it's still happening (albeit slowly) in areas that were covered by ice a few thousand years ago. The UK for instance.
Looks like it can promote earthquakes:
http://en.wikipedia.org/wiki/Post-glacial_rebound#State_of_Stress_and_Intraplate_Earthquakes

I'd bet that in an area where volcanism already exists, it may increase its likelihood, but it's not really likely to generate any melt and cause volcanism where there was none before.
 
matthyaouw said:
It's called isostatic uplift/rebound, and it's still happening (albeit slowly) in areas that were covered by ice a few thousand years ago. The UK for instance.
Looks like it can promote earthquakes:
http://en.wikipedia.org/wiki/Post-glacial_rebound#State_of_Stress_and_Intraplate_Earthquakes

I'd bet that in an area where volcanism already exists, it may increase its likelihood, but it's not really likely to generate any melt and cause volcanism where there was none before.

If you check out this ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/volcano.txt from the GISP-II ice core you will find unusual high volcanic activity during the last glacial transition, for instance about 10-11,000 years ago, around 12,700 years ago, 13,600 years ago, 15,000-17,000 years ago, etc,etc versus virtually none in prolongued periods. But I'm not sure about the causation, what is cause and what is effect?
 
Andre said:
If you check out this ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/greenland/summit/gisp2/chem/volcano.txt from the GISP-II ice core you will find unusual high volcanic activity during the last glacial transition, for instance about 10-11,000 years ago, around 12,700 years ago, 13,600 years ago, 15,000-17,000 years ago, etc,etc versus virtually none in prolongued periods. But I'm not sure about the causation, what is cause and what is effect?

Interesting. None of the volcanic areas I can think of were under ice sheets at any point (except kamchatka perhaps?). It's hard to imagine the increased volcanism being a direct effect.
 
matthyaouw said:
Interesting. None of the volcanic areas I can think of were under ice sheets at any point (except kamchatka perhaps?). It's hard to imagine the increased volcanism being a direct effect.

Not in Kamchatka, there was no ice sheet over there. The maximum extent of the Eurasian Weichselian ice sheet during the last glacial maximum (as posted earlier, source Hubberten et al 2004):

11uzx1w.jpg


Known areas with higher volcanic activity were the Volcan Eifel in Germany and the Massif Central in France

I do note that the mentioned active phases in the Volcan Eifel seem to be co dated with the up spikes of the 100,000 years seesaw cycle:

http://www.awi.de/typo3temp/pics/91b26f7eef.jpg

versus:

Rieden volcanic complex -- 380,000 to 430,000 years old in the WEVF. It consists of plagioclase-free fallout, flow deposits, and scoria cones in various compositional types (leucite-phonolite, nephelinite, leucitite).

Southeastern sector of EEVF -- around 215,000 to 225,000 years old. Basaltic (basanite and tephrite) scoria cones.

Niedermendiger lava flow -- between 100,000 to 150,000 years old. Major basaltic (tephrite) lava flow along with lesser alkalic (phonolite) eruptions in the EEVF.

Laacher See eruption -- about 13,000 years ago. Major eruption of alkalic (phonolite) tephra and pumice at the Laacher See volcano in the EEVF. Volume of erupted magma was approximately 5 km³, which equals or exceeds all mafic eruptions in the WEFV.

All perhaps roughly in the upspikes of the interglacials? But these dates are very coarse, but worth to narrow it down and see if there is a real correlation.
 
Last edited by a moderator: