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So here's a question. What event are we using as a metric for the "birth" of a rock? All the atoms are probably much older than the solar system and the process of the accretion disk grouping into rocks seems like it would be a largely gradual process. For super old earth rocks all the stuff we need to make rocks is just flowing in and out of the mantle over time so what is happening that we can measure as a birth event of those rocks all these billions of years later?
The "birth" of a rock can be considered when the magma for example turns solid. The small proportion of radioactive elements gets imbedded into the structure of the rock and some of the elements decay into elements which would normally gas out, but due to the solidity of the rock have no chance of escaping. Later when you want to analyse the age of the rock you can measure the gas content and calculate by that the age of the rock. Hope that makes sense
Sebastian Elytron You know Earth is jealous of Mars right? Lots of us even want to go there. We even have better pics of the entire surface of Mars than of Earth (most of Earth's surface is under water and we haven't don't much looking) She is not happy.
Putting aside the jokes, I really do hope the fallout from the florida tragedy leads to something productive, like the downfall of the NRA, and a actual discussion about how to solve the gun-issue.
steveXracer M8, I have some serious Poe's law issues here, I can't tell if you're a conservative troll or are normal person parodying a conservative troll.
To think of it, space is cold, and it's unlikely that Earth had a thick atmosphere 4.5 BYA as magma outgassing still had to build up, so seems plausible it would have solid crusty bits around
there should be a link to scishow.com in the description with all your other links, especially when you mention it. fb, twitter, tumblr, instagram, website.
I am confused how a rock can be older or younger? I get that we maybe guess a guess when a layer was formed based on the a volcanic eruptions but is that rock really older or younger? I mean how old is lava? Say you had a bucket of lava and threw some young rocks and old rocks into that bucket and melted it all into lava, then how old is it? Isn't everything the same age? That is like saying the water on the bottom of the ocean is older than the water on top. How can we know how many times these rocks and sediments have gone through these processes again and again. Matter cannot be created or destroyed so if you think about it all matter is the same age right?
I have always found saying that humans have been a blink in the geologic eye is a little misleading, due to scale. To properly scale the idea, imagine that you sit down in front of a wall, staring unblinkingly for 2 hours and 5 minutes. Then at the last moment, in 1/3 of a second, you blink. That is about how long the earth has been alive relative to humans. The math: Human life on earth: 200,000 years Age of earth: 4,500,000,000 Blink of an eye: 1/3 seconds Seconds per hour:3600 4,500,000,000/200,000 = 22,500 species lifetimes on earth 22,500/3=7,500 total species lifetime blinks in seconds 7,500/3600 = 2.083333 hours
Sounds to me like it is not that the hadean eon was cooler than previous hypothesised, but that it was shorter than previously hypothesised. If it was only 200 million years long, then some zircon crystals formed near the end of that period could survive.
You know considering that actual mythological Hades isn't a fiery hellscape the idea that the Hadean period wasn't as hot/fiery as we first thought is *more* accurate to the name.
Serious question: where are all the rocks from when the earth was formed? These rocks were only 4.4 billion years old, suggesting that there were OTHER rocks that were already there for 200 million years.
Interestingly, there's no mention here of the oldest crustal rocks on Earth, the Acasta Gneiss in the NWT of Canada. It is dated 4.2 to 3.9 Ga. I have a pal that staked a claim on the rock. He's sent me pieces of it. I call it my Genesis rock. I believe that the Acasta Gneiss and the zircon in Australia are related. At one time, a long long time ago, Australia was connected to the NWT of Canada. That's why the rock and the zircon are so close in age.
based on how certain atoms within the crystals had decayed... How do they know how things decayed before? Like they mentioned humans were not around to document anything; how can science ever really check their hypothesis, & have repeating results?
Michael Harig Supernovae explosions produce radioactive isotopes which produce gamma rays and the fading rates of those gamma rays can be measured. This has been done on various supernovae that are at various numbers of light years away from us so it tells us what the decay rates were at various points in history. And they are all consistent with today's decay rates.
BezoomnyBratchny how do they check or know things are the same without being able to get repeated results, since we won't be around billions of years from now to observe. Isn't their calculations based on what they guess about the past of earth was like? Isn't the present (human history/existence) the only thing science can accurately measure? To be scientific their must be observations, data collection, & repeatable results, none of which can't actually happen before human existence..?
Michael Harig I just explained how we can get repeatable results from the past. I'm not sure why you're repeating the claim that we can't get repeatable results and can't measure anything outside of the present.
BezoomnyBratchny I ask because I'd like to explain this to my "creationism" friends. I have to dumb it down, but be prepared to break it down for them. For my understanding you're saying that things outside our galaxy/ solar system tells how things work within our solar system. I can hear them now; how can we know if we've never "personally" measured anything because nothing has left our solar system... without a time machine how do we know physics has never changed..? The experiments on the space station would give us some information about space, but that's still within our galaxy, our solar system, earth's gravity... I've heard all these arguments & I'm trying to understand how to answer them without the rebuttal of "how do they know".
Michael Harig Ok, so let's take a few specific examples to make it more clear what I'm saying. There's a supernova called SN1987A. SN1987A is 169,000 light years away from earth. When SN1987A exploded, it produced lots of radioactive isotopes. Those isotopes produce gamma rays. Gamma rays travel at the speed of light. So, remember that SN1987A is 169,000 light years away from us. So, when the gamma rays reach us, they reach us 169,000 years after the explosion took place. So when we look at the gamma rays, we're literally looking 169,000 years into the past. And the fading rates of the gamma rays are consistent with the decay rates today. Therefore, the decay rates were the same 169,000 years ago as they are today. There's another supernova called SN1991T. SN1991T is 60,000,000 light years away from earth. And the gamma rays from that explosion are also consistent with today's decay rates. Therefore, the decay rates were the same 60 million years ago as they are today. And there's various other supernovae that go into the billions and they are consistent too. Every time we have checked at various points in history, the decay rates have always been the same as they are today.
I don't really see the problem with being off 600,000 years. That's not a large margin of error over 4.5 billion years. So maybe our accuracy of the Earth's age is off a tiny fraction more than we think it could be, and the Earth cooled just a very tiny bit faster than we think... 600,000 years is nothing. (Edit) By our age being off, I mean the Earth could be a few hundred thousand years older than we think)
Great question! We don't have our hosts on there yet. Olivia, Michael, Reid, and Brit come in just to film and they all have different schedules, so we're still getting their photos because we want to set up a lighting set up like we have for the rest of the team.
Oh, ok then. Stefan said the whole team was on the website, so that was confusing. She doesn't seem to have an instagram account, so I thought she had a "thing" about internet profiles, haha
Musa Mhlanga ...iam not a geologist but I have a question about rock-formation: based on the lower activity of the Sun billion of years ago was the cooling off the surface elevated and therefore solidification of certain minerals? Did some one ever found some air bubbles trapped in rocks this kind of age?
Geochronology (dating of rocks) is not my line of specialization nor is astrophysics (with regards to lower sun activity). This is what I know about solidification of minerals: As magma rises up through the crust it cools and minerals crystallize. If the cooling process happens quickly, only small crystals can form before the rock becomes solid resulting in what we call a fine grained rock ( with crystals less than 1 mm). If the cooling is slow (from decades to millions of years), then large crystals will form. Not only do you need elements to be present in sufficient quantities in order to form certain minerals, but you also need ideal physical and chemical conditions during magma emplacement (e.g) oxygen content, water, temp., pressure etc. So i'm sure not whether lower sun activity will have a profound effect on solidification (or crystallization) of certain minerals if any at all. But it has importance when it come to breaking down certain minerals by process of weathering and erosion leading to their redistribution and subsequent formation into other rock types (e.g sedimentary).
Lol we basically live on a giant piece of rock that floats endlessly in the vacuum of space. Makes sense to study it at the best of our capabilities. Not sure we deserve that 'Kardashian' rank at all
Musa Mhlanga ... fascinating! I asked in regards to gasintrapments because of the "faint young sun paradox" ... Maybe we have in a few years mass-spec techniques to determine gas compositions in early earth years that have diffused to the stone.
Can we just take a second to think about all the things that had to have gone right for life to start on Earth, and if a small detail may have changed we may not be here?
What you said is true. I just want to emphasize that some degree of belief is always involved in science. I often hear that "science is true whether you believe it or not". That's just not the case.
I think that little gem is typically reserved for people who enjoy asserting things such as the Earth is 6,000 years old and using scripture as evidence. Scripture ≠ convergent fields of scientific research as far as evidence is concerned. Scientific evidence converges upon the truth. And when it's modified, it's not necessarily proven "wrong," but typically expanded upon.
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Why is Michael missing on the "Team" page of the website? Please don't tell me he quit o:
Woohoo! Go us. Where are my fellow West Aussies? :)
Now for the toughest rocks: These Rock Hard ABS!
Obese Hank *Kidney Stone.
Muscle Hank then you wouldn't be able to move.
Muscle Hank Nothing my Chainsaw can't cut through.
Wtf with these hank
So many Hanks
Gonna steal some rocks to change history
Hustle Hank nice...... and I got robbed....
you missed a chance to say “steel”
Why isn't the geologist Hungry? He had no apatite.
Tom Meng impressive...most impressive...
Good jib! LOL
Gneiss one!
I changed history by posting here. I rock!
This is where I would expect Angry Old Hank to have something to say.
So here's a question. What event are we using as a metric for the "birth" of a rock? All the atoms are probably much older than the solar system and the process of the accretion disk grouping into rocks seems like it would be a largely gradual process. For super old earth rocks all the stuff we need to make rocks is just flowing in and out of the mantle over time so what is happening that we can measure as a birth event of those rocks all these billions of years later?
The "birth" of a rock can be considered when the magma for example turns solid. The small proportion of radioactive elements gets imbedded into the structure of the rock and some of the elements decay into elements which would normally gas out, but due to the solidity of the rock have no chance of escaping. Later when you want to analyse the age of the rock you can measure the gas content and calculate by that the age of the rock.
Hope that makes sense
When was the Earth's 4.5 billionth birthday and why wasn't I invited?? 😭 I'm only flirting with Mars I swear!!
[Passing cake to the next person] But, the last time I didn't receive a piece, and I was told...
Sebastian Elytron I don't know the year, but it was on april 22nd, called "earth day"
Every one was invited just because we are alive on earth.
Sebastian Elytron Yeah just like how you "flirted" with Venus for a few million years.
Sebastian Elytron
You know Earth is jealous of Mars right?
Lots of us even want to go there.
We even have better pics of the entire surface of Mars than of Earth (most of Earth's surface is under water and we haven't don't much looking)
She is not happy.
At 3:30, great to use the metric system. But with just a single significant digit those metric, short and long tons all round to the same value.
Jens Schmidt i
Love old rocks. Old rocks are the best rocks.
Geologist 1. Can we study the early Earth?
Geologist 2. We zircon.
Ba-dum tchh
Shale I say some puns? We shouldn't take you for granite.
Theft XD LOLOL
Delve
No problem. Please do. ^_^
sorry, the joke flew pass me. we zircon = we certain?
THEY ARE NOT ROCKS MARIE! THEY ARE *MINERALS*
Thanks for showing a picture of them.
Good info!!!
I miss the old days of chucking rocks at people as an efficient method of communication.
Kids these days don’t remember the good old days
You still can, but you have to put a QR code on it. Otherwise, people won't know what you're talking about.
You still can! Chuck a rock at somebody you don't like, I'm sure they'll get the general idea of what you're trying to communicate.
Putting aside the jokes, I really do hope the fallout from the florida tragedy leads to something productive, like the downfall of the NRA, and a actual discussion about how to solve the gun-issue.
steveXracer
M8, I have some serious Poe's law issues here, I can't tell if you're a conservative troll or are normal person parodying a conservative troll.
Where can we buy these crystal?
To think of it, space is cold, and it's unlikely that Earth had a thick atmosphere 4.5 BYA as magma outgassing still had to build up, so seems plausible it would have solid crusty bits around
Geology Rocks!
-_-
there should be a link to scishow.com in the description with all your other links, especially when you mention it. fb, twitter, tumblr, instagram, website.
I am confused how a rock can be older or younger? I get that we maybe guess a guess when a layer was formed based on the a volcanic eruptions but is that rock really older or younger? I mean how old is lava?
Say you had a bucket of lava and threw some young rocks and old rocks into that bucket and melted it all into lava, then how old is it? Isn't everything the same age? That is like saying the water on the bottom of the ocean is older than the water on top.
How can we know how many times these rocks and sediments have gone through these processes again and again. Matter cannot be created or destroyed so if you think about it all matter is the same age right?
Earth has been around or 4.5 billion years and yet so many of us live at the same time as Guy Fieri. W O K E.
Zircon makes me think of "Zenon: girl of the 21st century" for some reason.. 😁
My notification said "How the Oldest Rocks on Earth Chan.."
Matthew Conway more like small phone screen is small.
What kind of lunatic wants to collect moon rocks?
I get it x,D
I will not forgive you
I see what you did there...
@To the point. 'Lunatic' comes from 'Luna,' the name of our moon, due to the belief that the moon affected the mental state of people
Sounds like something you'd power a space ship with.
This gentleman is my favourite male SciShow presenter
Damn that cool early Earth! With all those zircons it must have had a Bedazzeler!
Which actor is a long-time favorite with rocks?
"The Rock"
yep
What's 600 million years between two Earthlings? A mere blink of an eye!
When science slaps creationism in the face
Turns out the Zircons had the evidence. I can't help but think about Steven Universe now.
I have always found saying that humans have been a blink in the geologic eye is a little misleading, due to scale. To properly scale the idea, imagine that you sit down in front of a wall, staring unblinkingly for 2 hours and 5 minutes. Then at the last moment, in 1/3 of a second, you blink. That is about how long the earth has been alive relative to humans.
The math:
Human life on earth: 200,000 years
Age of earth: 4,500,000,000
Blink of an eye: 1/3 seconds
Seconds per hour:3600
4,500,000,000/200,000 = 22,500 species lifetimes on earth
22,500/3=7,500 total species lifetime blinks in seconds
7,500/3600 = 2.083333 hours
You've been indoctrinated my friend. Snap out of it.
WoW. That haircut really changes Hank.
Sounds to me like it is not that the hadean eon was cooler than previous hypothesised, but that it was shorter than previously hypothesised. If it was only 200 million years long, then some zircon crystals formed near the end of that period could survive.
Mr. Zurkon doesn't need bolts, his currency is pain!
Whooo Hooo,
I'm from Perth Western Australia !
Everything fine until they realize they made a mistake dating it. Great video thank you!
The zircon crystals were discovered by a team from UW-Madison! I'm a proud alumnus and got to see the crystals at UW's geology museum.
You know considering that actual mythological Hades isn't a fiery hellscape the idea that the Hadean period wasn't as hot/fiery as we first thought is *more* accurate to the name.
Hadean period? So thats why they make Maxi pads...for those heavy hadean days.
Time travel, Zircon's, nothing was a it should be...getting Doctor Who vibes here :)
Issue #1 - Prove these crystals formed on Earth and didn't just land here relatively recently (in the past few hundred years) via a meteorite.
Most interesting.
Serious question: where are all the rocks from when the earth was formed? These rocks were only 4.4 billion years old, suggesting that there were OTHER rocks that were already there for 200 million years.
Interestingly, there's no mention here of the oldest crustal rocks on Earth, the Acasta Gneiss in the NWT of Canada. It is dated 4.2 to 3.9 Ga. I have a pal that staked a claim on the rock. He's sent me pieces of it. I call it my Genesis rock. I believe that the Acasta Gneiss and the zircon in Australia are related. At one time, a long long time ago, Australia was connected to the NWT of Canada. That's why the rock and the zircon are so close in age.
Zircon found in Australia are 200 million years older than the Shields.So is the Pilbara crust north of Jack Hills.
So much to learn....thanks dude for making it easier 🤣
but there is no michael aranda in the team section of the site!
I really like Stefan as a presenter. :)
The ziron crystal ight have come from the Theia Impact that created the Moon. Now you have another question... Which was cooler, Theia or Earth 1.0?
Damn, all I can say is that we are so young in terms of geological stand point.
Why not ask cranky old Hank, I'm sure he remembers those good ol' days.
Do you like my rock jokes?
I hope you don't take it for granite
Don't care how old this rock is, my favorite rock is still the rock
Liam Aaron Grant OF YAAAA SMEEEEELLLL!
Dwayne (the (Dwayne (the rock) Johnson) rock) Johnson
Kudos on pronouncing "micrometers" correctly :)
Elizabeth already exists when these rocks formed
More geology videos :D
What's a rock's favorite magazine?
The Rolling Stones
based on how certain atoms within the crystals had decayed... How do they know how things decayed before? Like they mentioned humans were not around to document anything; how can science ever really check their hypothesis, & have repeating results?
Michael Harig
Supernovae explosions produce radioactive isotopes which produce gamma rays and the fading rates of those gamma rays can be measured. This has been done on various supernovae that are at various numbers of light years away from us so it tells us what the decay rates were at various points in history. And they are all consistent with today's decay rates.
BezoomnyBratchny how do they check or know things are the same without being able to get repeated results, since we won't be around billions of years from now to observe. Isn't their calculations based on what they guess about the past of earth was like? Isn't the present (human history/existence) the only thing science can accurately measure? To be scientific their must be observations, data collection, & repeatable results, none of which can't actually happen before human existence..?
Michael Harig
I just explained how we can get repeatable results from the past. I'm not sure why you're repeating the claim that we can't get repeatable results and can't measure anything outside of the present.
BezoomnyBratchny I ask because I'd like to explain this to my "creationism" friends. I have to dumb it down, but be prepared to break it down for them. For my understanding you're saying that things outside our galaxy/ solar system tells how things work within our solar system. I can hear them now; how can we know if we've never "personally" measured anything because nothing has left our solar system... without a time machine how do we know physics has never changed..?
The experiments on the space station would give us some information about space, but that's still within our galaxy, our solar system, earth's gravity... I've heard all these arguments & I'm trying to understand how to answer them without the rebuttal of "how do they know".
Michael Harig
Ok, so let's take a few specific examples to make it more clear what I'm saying. There's a supernova called SN1987A. SN1987A is 169,000 light years away from earth. When SN1987A exploded, it produced lots of radioactive isotopes. Those isotopes produce gamma rays. Gamma rays travel at the speed of light. So, remember that SN1987A is 169,000 light years away from us. So, when the gamma rays reach us, they reach us 169,000 years after the explosion took place. So when we look at the gamma rays, we're literally looking 169,000 years into the past. And the fading rates of the gamma rays are consistent with the decay rates today. Therefore, the decay rates were the same 169,000 years ago as they are today. There's another supernova called SN1991T. SN1991T is 60,000,000 light years away from earth. And the gamma rays from that explosion are also consistent with today's decay rates. Therefore, the decay rates were the same 60 million years ago as they are today. And there's various other supernovae that go into the billions and they are consistent too. Every time we have checked at various points in history, the decay rates have always been the same as they are today.
That thumbnail... lol
Thanks. Now I don’t feel so guilty about buying my wife a cubic zirconia ring. 😜
wow, and i always took these things for granit...
I do have a piece of zircon from jack hills…
I don't really see the problem with being off 600,000 years.
That's not a large margin of error over 4.5 billion years. So maybe our accuracy of the Earth's age is off a tiny fraction more than we think it could be, and the Earth cooled just a very tiny bit faster than we think...
600,000 years is nothing.
(Edit)
By our age being off, I mean the Earth could be a few hundred thousand years older than we think)
Why isn't Olivia on the website??
Great question! We don't have our hosts on there yet. Olivia, Michael, Reid, and Brit come in just to film and they all have different schedules, so we're still getting their photos because we want to set up a lighting set up like we have for the rest of the team.
Oh, ok then. Stefan said the whole team was on the website, so that was confusing. She doesn't seem to have an instagram account, so I thought she had a "thing" about internet profiles, haha
nice
Woohoo! Go us. Where are my fellow West Aussies? :)
these Hanks are gradually turning into the Gog and Magog army....the END is Nigh.
Earth is a giant rock with water
my teacher said that World 2nd Oldest Rock is in our town so I was shocked to hear this . But people no one knows about it . No body care thi rock 🪨.
I just watched a video in science about this...
Illuminati Concerned
Anyone else here a geologist?
Musa Mhlanga ...iam not a geologist but I have a question about rock-formation: based on the lower activity of the Sun billion of years ago was the cooling off the surface elevated and therefore solidification of certain minerals? Did some one ever found some air bubbles trapped in rocks this kind of age?
geology is like the Kardasians of science
Geochronology (dating of rocks) is not my line of specialization nor is astrophysics (with regards to lower sun activity). This is what I know about solidification of minerals: As magma rises up through the crust it cools and minerals crystallize. If the cooling process happens quickly, only small crystals can form before the rock becomes solid resulting in what we call a fine grained rock ( with crystals less than 1 mm). If the cooling is slow (from decades to millions of years), then large crystals will form. Not only do you need elements to be present in sufficient quantities in order to form certain minerals, but you also need ideal physical and chemical conditions during magma emplacement (e.g) oxygen content, water, temp., pressure etc. So i'm sure not whether lower sun activity will have a profound effect on solidification (or crystallization) of certain minerals if any at all. But it has importance when it come to breaking down certain minerals by process of weathering and erosion leading to their redistribution and subsequent formation into other rock types (e.g sedimentary).
Lol we basically live on a giant piece of rock that floats endlessly in the vacuum of space. Makes sense to study it at the best of our capabilities. Not sure we deserve that 'Kardashian' rank at all
Musa Mhlanga ... fascinating! I asked in regards to gasintrapments because of the "faint young sun paradox" ... Maybe we have in a few years mass-spec techniques to determine gas compositions in early earth years that have diffused to the stone.
What if the method of dating used was just a little bit off?
no Hawking special?
ruclips.net/video/-3iFozbw_pE/видео.html
SciShow no about his life
How do they know wether a rock was formed on earth or stems from a meteorit?
So cool
Oh god who tore a hole in the multiverse? Too many Hanks are leaking into the comments, we cant handle it!!!
Age is just a number
R is obviously a letter.
Bob Hope no it’s not :|
Do you know what a pirate's favorite letter is?
Their only true love is the C.
Bob Hope 🤣 Wow...
I like rocks
Dont read my picture but i just did
Do you like this song? ruclips.net/video/SRwrg0db_zY/видео.html
I like turtles.
They're minerals, Marie!
They never mentioned the Acasta Gneiss :( makes my geology brain hurt
I'm a big fan of rocks. When I was a little kid, the bottom drawer of my 3-drawer dresser was full of pretty or unusual rocks.
So, how old are my Zircon encrusted tweezers?
Jewel Encrusted Blade?
How the solar system was formed?
Verónica Darrell Big Bang!
The host looks like Frank Grimes.
I was told the earth is only 6000 years old and it was formed by a magic sky man
How can you fart without "stuff" leaking out?
Paule Patterson , the trick is to make sure you're really dehydrated, then fart very carefully.
Eat plenty of sand. Eventually your farts will be dry as the Sahara.
Crazy to think us human have been here for such little time but caused so much damage, we're like the earths plague 😳
I'm pretty sure the oldest stones ARE the history...
Top 10
Can we just take a second to think about all the things that had to have gone right for life to start on Earth, and if a small detail may have changed we may not be here?
Or maybe evolution in a different climate might have changed things
Rock = Colonel Sanders
i only clicked this to be early lol
XD
Or could the earth be older then estimated?
reezdog than*
Shawn Caton thanks :)
Maybe
See, science is about believing. Because we can never have a complete facts.
Science is about testing evidence. It's true we don't have all the facts, but that doesn't make all claims equally valid.
What you said is true. I just want to emphasize that some degree of belief is always involved in science. I often hear that "science is true whether you believe it or not". That's just not the case.
I think that little gem is typically reserved for people who enjoy asserting things such as the Earth is 6,000 years old and using scripture as evidence. Scripture ≠ convergent fields of scientific research as far as evidence is concerned. Scientific evidence converges upon the truth. And when it's modified, it's not necessarily proven "wrong," but typically expanded upon.
Rock
Where is the "Madina lake" guy i miss him and his sexy hair ):
Where does a rock sleep?
Bed rock
I'm *stoned*
Bam
Aussie Aussie Aussie......
Rocks are for the weak