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Scientists Have Finally Sampled the Most Abundant Material On Earth
rossgneumann writes: The most abundant material on Earth didn't have a name, and, in fact, hadn't been seen — until now. For the first time ever, scientists have gotten their hands on a sample of bridgmanite, a mineral that is believed to make up more than a third of the volume of the Earth. In a new paper published in Science late last week, Oliver Tschauner of the University of Nevada, Las Vegas, and his team describe bridgmanite for the first time.
actually the total amount of water would only cover the entire surface with a uniform layer one fifteenth of one percent the total radius of the planet. Water is in fact, therefore, pretty scarce on Earth.
Political debates have me rolling my eyes so much I think I got optical whiplash. I should sue. - Foamy The Squirrel
Water is in fact, therefore, pretty scarce on Earth.
That's like arguing the material a balloon is made of is scarce on a balloon. Its true that there's not much of it in the total volume of a balloon. But it still makes up pretty much 100% of the surface area ON a balloon.
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Two strikes for you - first you make a poor analogy (In a completely deflated state the rubber is the entire volume and mass of the balloon), and second you missed the opportunity to make it a car analogy.
A better analogy would be that paint (or enamel) is pretty scarce on a car since such a tiny fraction of its total mass consists of paint, even though us "surfacists" consider the paint a very important characteristic of the car.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
Interesting.
But the summary is slightly misleding. The stuff they found came from a shocked meteorite. And it fits the theoretical models of the makeup of the lower mantle. But it sounds like we still haven't gotten a significant sample from inside the earth to validate the theory.
Have gnu, will travel.
This was sort of my point. It is my understanding that the correct structure of Bridgemanite is not stable on the surface of the earth. So what we find lying around are samples that have been cooled and decompressed.
One of my hobbies involves hardening and annealing metal. And time at temperature is a critical factor (fast vs slow cooling) to produce the desired material characteristics. So I'm not convinced that the stuff inside a meteorite, which experiences these extremes for only a few seconds correctly duplicates something that has been exposed for a few billion years.
Have gnu, will travel.