Antarctic Canyons

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Antarctic Canyons

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maj 24, 2018, 6:58pm

Research on these hidden canyons and mountains has been ongoing for several years ... but details about exactly where they are located is still not very clear. Published images and maps show only rough ideas of their extraordinary sizes ... but they appear to be larger and deeper than the Grand Canyon.

maj 24, 2018, 10:25pm

Interesting. And the article points out that these are important in the face of global warming as they may channel water from the interior to the coasts.

maj 25, 2018, 5:54am

Forgive my question, but these canyons would have to be formed over millennia by water, right? So this was obviously when the earth was much warmer. Any idea when Antarctica was (or mostly) free of ice? This is not an area of study for which I have much knowledge. Half jokingly, I'll say I was raised & schooled by creationists and I'm still playing catch-up.

maj 25, 2018, 6:29am

The Antarctic Continent was not always at the South Pole. 200 million years ago it was closer to the Equator as part of the Gondwana Land Mass. Subsequent Continental Drift has resulted in its present position. It was not so much that the earth was warmer, more that the continent was in a warmer place (though the Earths temperature has varied over time - witness the ice-ages not so very long ago, most recently 13000 years ago)

Continental drift results in some significant changes, 450 million years ago England was in the Southern hemisphere.

maj 25, 2018, 9:29am

>4 BobH1: Ah, thanks! I'd forgotten continental drift. I need to go back to science class.

maj 25, 2018, 11:24am

General principle of Earth science: just because something is one way now, don’t assume it wasn’t radically different in the past.

maj 25, 2018, 2:29pm

3>Pmackey ... The Antarctic canyons were probably cut more by glacial ice, than by moving water. For instance, all the deep fjords along the western coast of Norway were carved by moving ice...during the Ice Age. See paragraph 7, below:

jun 8, 2018, 9:08am

>7 Rood: Thanks. I was thinking of the Grand Canyon which was why I was thinking water flow. Honestly, though, I didn't know about the Norwegian fjords being carved by ice. Glad to learn!

jun 8, 2018, 9:40am

>8 pmackey: A lot of North American geological character owes its origins to ice flow. Glaciers carved out the Great Lakes.

jun 8, 2018, 10:23am

>9 southernbooklady: Thankfully, I was aware of that living in North America and -- perhaps -- paying attention in geography class. When I think of canyons, again because I'm a North American, I think of the American West.

One of the things I like about LT is we touch on so many topics and I always learn something. I'm old enough to know there's so much I don't know. It's humbling. But I like learning, so it's exciting, too.

jun 8, 2018, 10:33am

>10 pmackey: Speaking or covering so many topics, I have a surprise that I will be announcing, hopefully over this weekend time permitting. It’s exciting. Stay tuned...

jun 8, 2018, 10:42am

>11 stellarexplorer: Seriously?!? You leave us hanging like that? I hate waiting. May great things unfold for you and yours and I look forward to your announcement.

jun 8, 2018, 11:02am

Thanks. I just wanted to start some buzz. Hint: this group, among other things, has contributed to my finding a new venture to sink my teeth into. Very excited.

jun 8, 2018, 11:03am

Check back tonight or tomorrow. Sorry to be obscure, but I want to get the phrasing right.

jun 8, 2018, 11:14am

Standing by....

jun 8, 2018, 2:07pm

Oh come on Stella ! Don't let us wait !

jun 8, 2018, 2:28pm

Ok, I’ll commit to today. I’ll try for this afternoon, but at the latest, this evening.

Sheesh. I succumb to peer pressure ;-)

jun 8, 2018, 4:46pm

Venture explained in separate thread.

jun 13, 2018, 9:05pm

Not good.
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