How North America Almost Separated Into Two Pieces

It's hard to believe, but did you know North America almost split itself in two? 1.1 billion years ago, the land almost separated into two halves— and had it succeeded, there would now be an ocean where Lake Superior is! Learn all about this crazy separation with Hank in a new episode of SciShow!

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[kayakat]

That's why there are a bunch of beautiful tiny mountains in northern Minnesota. They are all little extinct volcanoes, and I think that's pretty neat.

[philpaine]

I spent my early childhood in Northern Ontario, with the Canadian Shield under my feet. The stone everywhere was as hard as the strongest steel. Even the simplest construction --- digging a basement, laying down a sidewalk, or laying pipes, required endless blasting. As a result, every kid had access to the dynamite caps that were tossed about in the explosions. So much dynamite was floating around that some clever kids even had dynamite sticks, as well as the caps. It was a favourite game to launch empty tomato cans into the air with these toys. Later on, I visited places like Arizona, where "rocks" turned out to be crumbly stuff with the consistency of cheese.

[espjoshua]

So THAT'S why I can't seem to lose weight! The density of the rocks under my bathroom scale must cause increased gravity at that point and the weight registers higher! What a relief...I thought it was just my bad diet and lack of exercise.

[TheRogueWolf]

Political pundits: "America has never been so divided."

Geologists: "Well, we came close one time...."

[jamesburgessk]

Learning about tectonic plates can be a coin toss on being either extremely boring or interesting as hell

[TheLucidDreamer]

North America 1 billion years ago: *destroying itself*
North America today: *destroying itself*

[InstallaFriend]

They went to counselling and with a lot of long and hard work, they saved their relationship

[jessjitsu]

Little known fact about the state of Minnesota, my home state... We are actually at risk for seismic activity near this Rift... But not because of the failed Rift itself, but because the ground here is still inflating after the compression it took during the Ice Age. The Upper Midwest is a very cool geological place :-)

[Swanke]

Yeah well, it's kinda trying to do that right now..

[theotherVLF]

We just learned about this today in my geology class! What a coincidence.

[cinderball]

Be real here - if you hadn't watched this video, the "Midcontinent Gravity High" would either sound like the world's coolest high school, or the world's most illegal drug.

[whtbobwntsbobget]

1:40 Gravity maps are REALLY useful for nuclear war. The gravity inconsistencies are enough to throw off the accuracy of an ICBM. So having accurate maps was VERY important to the military.

Just thought I'd throw that in there! :)

[aldenconsolver]

Good Job to SciShow, a difficult part of the geology of the mid-continent explained pretty well in just 10 minutes - and this is from a geologist who lives in Kansas. Most instructors would not have even finished up confusing the students when you had moved on to glaciers 15000 years ago when you started out at a billion

[horset]

I vaguely remember my grade 2 teacher talk about this.
Though she didn't go into it with much detail. Got to the point many years later where I thought she might've gotten her facts wrong or something. Good to know that she wasn't entirely wrong!

[ScrybeSG]

I travel for work professionally. I collect unique mementos from wherever I go. I have a sample of volcanic basalt laced with olivine as a souvenir from my time in Wisconsin (near Brule River State Park). They use it as loose road gravel. This is where it came from. :)

[hgbugalou]

The New Madrid fault is thought to be related to the intrusion of magma into the crustal rock causing major density differences in horizontal strata.

[beaurenov]

When he says "1.1 Billion years", the .1 is still 100 million years

[johnopalko]

I saw the title and immediately began singing:

"Oh, the land sank down and the ocean hurried in
And we lost a fifth of our geography.
Nearly fourteen million souls found their way to Heaven's rolls
With the coming of The Great Nebraska Sea."

It's a filk song by Blake Hodgetts and is based on a 1963 short story by Allan Danzig.

[post-leftluddite]

If anyone is really interested in geology like I am, look up a documentary series by the BBC from called "Earth Story" hosted by Aubrey Manning.... It's THE BEST history of the earth series I've ever seen and it's because it doesn't just tell you what they know, it explains how they figured it out, when they figured it out, and who figured it out, which I love because if you're intelligent, you don't just want to know the facts, but how they were arrived at.

[systlin]

Live in Iowa, so this runs literally almost right under my feet. The Plum River fault, a remnant of this, is not far at all from my house.
Strange to think that the land I walk on every day was once such a geologically active place.