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 stated “microbes
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.