Experts seek explanation after glacial lake disappears in southern Chile

[kurth]

Experts seek explanation after glacial lake disappears in southern Chile
June 20, 2007

SANTIAGO, Chile (AP) - A glacial lake in Chile's southern Andes has disappeared and scientists want to know why.

The disappearance of the two-hectare lake in Bernardo O'Higgins National Park was discovered in late May by park rangers. Where the lake had been in March, they found a dry crater 30-metres deep and several large pieces of ice that used to float atop the water.

"The lake had simply disappeared," Juan Jose Romero, head of Chile's National Forest Service in the southernmost region Magallanes, said Wednesday. "No one knows what happened."...

One theory is the water disappeared through cracks in the lake bottom into underground fissures. But experts do not know why the cracks would have appeared because there have been no earthquakes reported in the area recently, Romero said.

http://www.canada.com/topics/news/world/story.html?id=3f088a10-7391-42dc-8124-41c35c8748e7&k=2425

[Bobbieo]

1. How about possible mining in the area?

[Kiouni]

2. That's nuts!

But you would think if we can look for water on Mars we can find it in the ground here.

[EC]

3. Okay, wasn't Jeb just in Chile?

:tinfoilhat: And isn't GW's land just over the mountains east of Chile? Wasn't there something about GW's land and Moonies land being water sheds or having influence on the glacial run-offs? I wonder what they are doing down there, more than ever now...I wonder how many more lakes will disappear?

[Viva_La_Revolution]

4. Aliens.

UFO's run on water.


:evilgrin:

[Nihil]

5. Oops?

"So that's what the chain was attached to?"

Ok, on a more serious note, that volume of water being "suddenly" added
to anything other than a damn big cave is likely to cause problems ...

At best it will involve flooding as "lost" rivers reappear.

At worst it will involve landslips, mudslides and subsidence (and flooding!)
due to the lubricating effect (not to mention potentially dissolving
depending on the rock types).

[Xithras]

6. Why cracks would have appeared. (picture of the lake)

This park is a glacier filled frozen island, and it's in the southern hemisphere...so it's winter there right now. What does ice do when it freezes? It expands. What does ice do in a crack when it freezes? It makes the crack bigger.

My guess would be that the freezing lake finally cracked through to another basin or cave, or that the rock along one side is fissured enough to allow water to run out of the basin faster than it runs in.

It's cool to see, because these kinds of things don't happen very often, but it's a great display of the impermanence of nature. Ice made the lake, and ice may have destroyed it.

On edit:

I found another article with pictures of the lake, which introduces another possibility: http://www.usatoday.com/tech/world/2007-06-21-chile-lake-vanishes_N.htm. As you can see in the photos, the glacier extends right into the lake. If the glacier is receding, it may have exposed cracks or underground caves that had been previously plugged by the ice. Glacial lakes like this one also tend to form between the terminal moraine and the glacial head. If the glacier calved and caused a wave in the lake, it might have weakened the moraine enough to permit water through.