If Antarctica was to thaw...would we find anything?

[RichF]

So Antarctica began to break apart from Gondwana 160 million years ago, glaciers began to form 38 million years ago and it has existed under an icecap for the last 5 million years. If it was to thaw out tomorrow, would we find any biological history or would the damage due to glacieral shifts have pretty much destroyed any evidence? Personally, I find the concept very interesting!!!!

 

http://www.secretsoftheice.org/explore/past.html

 

[CPL.Luke]

I remember from the program "walking with dinasaurs" that they have evidence that there were dinasaurs on antarctica 100 million years ago

[RichF]

That makes sense due to the glacial formations not occurring until 38 million years ago. However, glaciers tend to carve/grind up everything in their path. Could any evidence have survived? Beyond biological evidence, would we find anything else of interest?

[JesuBungle]

Apart from fossils, there would be quite a cache of meteorites, which I'm extremely interested in.

[Mokele]

However, glaciers tend to carve/grind up everything in their path.

 

I know they do elsewhere, but is that the case in antarctica? I was under the impression (possibly mistaken) that apart from a few places, the whole continent was pretty much flat, like Australia. Is there still a lot of glacial movement?

 

Mokele

[Sisyphus]

Antarctica is the most mountainous continent on Earth, but there are large flat regions, as well. I don't think there's much movement aside from the coastal regions, though.

[RichF]

Antarctica is the most mountainous continent on Earth, but there are large flat regions, as well.

 

Cool...I did not know that! Does anyone have a good link for the geological history of the Antarctic coninent? I had some trouble finding one. Oh yeah...any one have a map of the land structure under the ice as I am really curious as to what she actually looks like declothed!!!

 

As far as meteorites go I stuck another post up regarding tectonic plate movement. I found the info while looking for Antarctic history. Apparently, 250 million years ago a humongous asteroid split the Antarctic and Australian continental plates. I thought they were two different topics..thus the two threads.

 

I was checking out the location of the Tsar Bomba detonation location on Google Earth the other day (73.85° N 54.50° E , over Mityushikha Bay) and if you scroll north and look around you can see a few nicely preserved meteor impact craters. I imagine that the polar ice has protected them?

[silkworm]

Cool Facts about Antarctica

 

This one is my personal favorites:

 

2/ Antarctica is pushed into the earth by the weight of its ice sheets. If they melted, it would "spring back" about 500m (1 625 ft). It would do this v...e...r...y s...l...o...w...l...y taking about 10000 years to do so.

 

Scotland and Scandinavia are still rebounding today after the last ice age - at the rate of half a meter a century in the Northern Baltic - the fastest place.

 

A few more:

 

10/ Snow falling at the South Pole takes about 100 000 years to "flow" to the coast of Antarctica before it drops off the end as part of an iceberg.

11/ The Antarctic ice cap has 29 million cubic kilometres of ice. This is 90% of all the ice on the planet and between 60 and 70 % of all of the world's fresh water.

 

Only about 0.4 percent of Antarctica is not covered by ice

.

 

12/ Antarctica has a peculiar group of fish called the ice fish. These have no red pigment - haemoglobin - in their blood to carry oxygen around. Because the temperature is so low and oxygen dissolves better in cold temperatures, they get by perfectly well without it. They just have a larger volume of clear blood instead and so unusually have a ghostly white colour, particularly their gills.

 

These ice fish have recently been shown to have their DNA damaged by high levels of ultra violet light resulting from the ozone hole (they have less pigment to prevent the UV getting through).

 

Many other Antarctic sea creatures including fish have antifreeze in their blood so they don't accidentally get frozen solid!

[AzurePhoenix]

I remember from the program "walking with dinasaurs" that they have evidence that there were dinasaurs on antarctica 100 million years ago

Off the top of my head I can recall them finding a therapod dino called cryolophosaurus and some other, an iguanodont, a hadrosaur, and the hypsilophodont featured in that "Walking With" episode. I imagine if the ice melted they'd have much easier access to potential fossils, but then again, wouldn't the melting of the ice and the movement of all that water potentially sweep alot away?

 

As for meteors, I was under the impression that it doesn't have any more than eslewhere, it's just that they stand out darkly against all the ice, and if that's the case, after the melt there would be ALOT of bare rock for them to hide in.

 

I imagine a dethawed and dried out anarctica would be a boon to geologists though, and wouldn't it give much better access to potential oil-hunters?

[AzurePhoenix]

As for meteors, I was under the impression that it doesn't have any more than eslewhere, it's just that they stand out darkly against all the ice

So sue me, I was half-wrong yet again; seems that the meteorites get carried by the movement of ice so they build up in certain areas. They're rather well preserved too.

[olifhar]

A little OT, but I swear this picture from the page that Silkworm linked (very nice, btw) looks like the background in the beginning of Daler Mehndi's Tunak Tunak video...

 

[RichF]

and it has some pretty cool maps too!!!

 

http://www.coolantarctica.com/gallery/views_of_antarctica.htm

 

 

I don't know how I missed this image on wikipedia...

 

 

Hi-Res

http://upload.wikimedia.org/wikipedia/commons/e/e0/AntarcticaRockSurface.jpg

 

Antarctica without its ice-shield. This map does not consider that sea level would rise because of the melted ice, nor that the landmass would rise by several hundred meters over a few tens of thousands of years after the weight of the ice was no longer depressing the landmass.

[silverslith]

The ice is some 7km thick and WAS hanging over the edge of the continent by around 100km in 1000m thick shelves. In the last twenty years most of this overhang has been lost in accelerating melt. What happens when this Ice Skirt is fully gone and with it a major cooling system of a the worlds oceans is a serious concern. We may see rapid all-ocean warming with thermal expansion driving rapid sealevel rise ( I think claiming sealevel rise is the result of additional water freed up by melting glaciers is something of a whitewash aimed more at pacifying peoples concerns). This sort of thing happened cyclically about 100 times between 30000 and 5000 years ago with major instability in sea levels of up to 100m. Largely due to periodic melt and refreeze of the north atlantic ice sheet and its affect on the gulf stream.

This mass of ice seems like it would depress the sthern continent by more than 0.5 km, though isostatic equilibrium of continents is achieved slowly.

The most recent fossils would have been ground to dust by the constant spreading of the ice sheet. Dinosaur ones in hard deep rock may have survived.

 

A major curiosity is the 15th centry map of a portugese sea captain which was "compiled from ancient maps" and shows the coastline of antarctica in amazingly accurate detail that was only recently mapped by satellite radar- as its supposed to have been hidden by all that Ice for sometime.

[Pleiades]

Ever since I saw a documentary on penguins, I’ve wondered about what happens when they die. If they die on the ice and freeze, why isn’t the ground simply a mass of frozen penguins? They can’t rot, and they can’t be eaten once they freeze, so where do they go?