Well, National Geographic further explains that this area actually used to be part of an incredibly old ocean—the Iapetus Ocean—which covered the region millions of years ago. Then a piece of land broke off what is now known as South America and Africa, making its way towards North America and, thus, closing off the ocean.
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Community Rules apply to all content you upload or otherwise submit to this site. That is the reason I have given up reading on so many "social science" articles. They have anecdote after anecdote, and take their sweet time to come to their point. And usually their point would be moot.
Back when I learned how to write articles, we were told to start with the actual idea, and open it up, not the other way around. To reiterate: anecdote! As always: Not saying it's wrong. But that without that, it's anywhere between useless and harmful, even if it would be true. You know: The ternary logic of knowledge: Yes, no, dunno. Layman geology enthusiast here. They know it's from the mantle primarily by the unique combination of the minerals and rocks that are present in the samples they dug up.
By "unique" I mean they bear no resemblance to other surrounding rock. You're looking at rocks that are formed by one process, and then bang in the middle, a pocket of rock formed by an entirely different process. The rocks being discussed here are "ophiolites" -- rocks composed of the same kind of minerals one finds in places like the mid-Atlantic ridge, not the weathered remains of the Appalachian mountains where they dug it up.
But, there they are. Like, the simplest: How does a geologist ever get started then? He looks at the ground beneath him and determines its composition. Then he walks somewhere else where the ground is different, and determines its composition. Following your argument, since it is different than what he knew before, it must have come from the mantle. But why? Or is it a requirement that it is surrounded by the first type of ground? And if yes, then is there a size requi.
There's about a dozen paragraphs that describe it in bits in a pieces, so it's worth reading the whole thing, but perhaps the 1 best part I could extract from the article is:. The key, Guice says, is in the chemistry of the mantle. The upper mantle is frequently melted a little bit at a time, but different minerals melt at different temperatures.
So when the mantle partially melts, it becomes increasingly devoid of a predictable series of elements, which creates a specific chemical fingerprint. Ok, that's useful. Now I of course still wonder if they checked how melted the mantle is. I mean drilled down to it and took a look.
And yes, ain't nobody got time to read a 12 page whatever just for that one bit. That's why I use Slashdot, after all! To condense it to the gold nuggets. Like ALL of quantum physics, relativity, neurology, psychology,. There was a proposed attempt to drill down into the mantle and examine it in situ , Project Mohole [nasonline. The deepest drilled hole to date was the Soviet Kola Superdeep Borehole [bbc.
That's deep Then go and read the frigging paper. Don't be some slashdotting "I know better than the experts do" naysayer at the drop of a hat. You read the title. Possibly you read the first paragraph. And now you're all pish-poshing it because you had a gut feeling that they must be wrong because they are experts, and experts are always wrong.
You're strongly mplying that there is no evidence or logic or experiments at all without taking any effort to find this out first. I guess they know the same way we know there are planets around other stars, by inference rather than direct observation. Not for a lack of trying. One of Canada's National Parks will let you dance on it or anything you like.
The OP Article makes it sound like a unique discovery. I think this is "rare" in the sense that rare earth metals are "rare": i. The vegetation struggle in the poor soil derived from the serpentine rocks. There is an abandoned chromite pit mine where they collected one of their samples. Yes, Soldier's Delight is a neat hiking area.
You can really see the exposed geology, and the very sparse scrubby conditions due to the lack of soil. I hiked there last fall. Start your Independent Premium subscription today. More about Maryland Baltimore. Already subscribed? Log in. Forgotten your password? Want an ad-free experience?
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