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  • So, guys, I just learned that drilling into the earth can tell us about outer space.

  • What is going on here?!

  • Hi guys, Lissette here for DNews.

  • Scientists are drilling into the earth.

  • We all know the Earth is made of three major layers - the core, mantle, and crust, which

  • is where we all live.

  • The crust floats on the mantle, a super-thick layer of mostly slowly moving rock.

  • We've been trying to reach the mantle since the 1960s, but despite numerous expeditions,

  • have still not dug past the crust.

  • By all accounts, attempting to reach the mantle is dangerous and expensive, so why are we

  • trying so hard to get down there?

  • Because the mantle can tell us a lot about the history and formation of our planet in

  • the universe.

  • The mantle makes up 84% of the Earth's volume and is incredibly hot with temperatures that

  • range from around 1000 degrees celsius close to the crust and about 4000 degrees celsius

  • near the core.

  • The weight of everything above it creates pressure that builds up tremendously the closer

  • we get to the core.

  • The crust varies from 5 to 60 km thick, with the thinnest layers found under the ocean.

  • The farthest we've gotten was in the 1980s in Russia's Kola peninsula, where they dug

  • for 20 years and managed a 12 kilometer-deep hole, which was probably not even halfway

  • to the mantle.

  • This and many expeditions have failed because of technical difficulties like improper equipment

  • and just plain bad luck in choosing spots to drill.

  • But this doesn't mean scientists have given up.

  • More recently, a team of scientists from the International Ocean Discovery Program (IODP)

  • drilled into the ocean crust and were able to retrieve rocks that showed signs of life

  • . We're not talking about mole people or green big eyed kind of life, but microbial life.

  • The rocks contained methane and hydrogen, which as one of the researchers statedmicrobes

  • can 'eat' to grow and form new cells”.

  • This is huge!

  • Similar rocks, gases, and conditions are found in other planets.

  • So, according to the researchers, these rock specimens can aid our search and understanding

  • of how extraterrestrial life may exist in similar inhospitable conditions in the depths

  • of the universe.

  • But reaching the mantle doesn't just teach us about space, it also teaches us about earth.

  • The mantle's activity is largely responsible for the movement of tectonic plates, which

  • scientists theorize influences volcanic activity, earthquakes, mountain ranges, and movement

  • in the oceans.

  • So understanding the mantle more can help us better understand the earth's current

  • topography and it's history - Including how our continents shifted throughout the

  • ages and are shifting today.

  • If we can drill down to the mantle, researchers could have this type of information straight

  • from the source, increasing the accuracy.

  • Right now we can only make inferences about the structure of the earth based on how fast

  • an earthquake's' seismic waves, travel through the planet and the routes they take, what

  • we can see on the crust, and the composition of rock samples.

  • It wasn't too long ago that by chance a volcano ejected a diamond from the mantle

  • that confirmed that there is an ocean's worth of water in the mantle's transition

  • zone!

  • Scientists learned this because it contained ringwoodite, with a certain amount of water

  • in it.

  • This tiny rock made a huge difference.

  • And look, these rocks are great, but they are inconsistent - we don't know when the

  • next mantle rock will be spewed out of which volcano or if it will be intact enough for

  • scientists to derive meaningful conclusions.

  • We got lucky with this diamond, but often these rocks are too damaged.

  • Most have been belched out from volcanoes, ejected by tectonic plate crashes, or carried

  • upward to the ocean floor.

  • These treacherous and often erratic journeys leave scars on them, and leave scientists

  • with messy data.

  • It's hard to know what characteristics were a result of the journey vs reflective of the

  • mantle itself.

  • So drilling down to the mantle could mean that we would finally be able to get pristine

  • samples of the mantle, and even an entryway for further exploration.

  • It could give us a clear look at the mantle's composition, how it's moving, and more accurate

  • readings of its velocity, pressure, and temperature.

  • In essence, what the earth and possibly the universe is made of.

  • But the drilling we most often hear of is tied to oil.

  • To learn where oil comes from, check out this video over on TestTube News.

So, guys, I just learned that drilling into the earth can tell us about outer space.

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通过钻入地幔我们可以学到什么?(What Can We Learn By Drilling Into The Earth's Mantle?)

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    joey joey 發佈於 2021 年 04 月 16 日
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