Methods of Dating the Earth Part 1: Relative Dating

We've learned about all the enormous time spans that describe the billions of years in Earth's history, but how did we arrive at these dates? How can we know the age of the Earth? Let's learn about some dating methods, starting with relative dating. This is where we use stratigraphic sequences to tell roughly how old a rock is.
Script by Jared Matteucci
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[@Brain-washed2]

I was pretty nervous about asking her out, I’m sure after this video I’ll have the confidence I need. Thanks Prof. Dave

[@christopherstanford5599]

😅😂

[@5gallonsofwater495]

BAHAHAHA i also misunderstood the title at first glance

[@wworsey954]

Pls don't date ur relatives

[@kellydalstok8900]

💎💍

[@kylemoore7746]

@@wworsey954 considering we're all related 🤷‍♂

[@Lorbius]

So glad someone like Professor Dave is explaining stuff like this to me. It’s so easy to understand stuff with him.

[@matteofinazzi5087]

Professor Dave coming thru with the dating advice we all needed

[@this_is_patrick]

Thanks for the dating tips, Prof!

[@mjjoe76]

Places where people date their relatives are also places where Young Earth Creationism is widely accepted. 🤔

[@howdoeatjerry3975]

Glad to see that Dave is back to making his usual tutorials. I was concerned for a minute that he was just doing debunking, but here he is, proving me wrong.

[@Its_Shaun_the_Sheep]

You got debunked 😂

[@user-vm3dd4yd2l]

huh?@@Its_Shaun_the_Sheep

[@user-vm3dd4yd2l]

🤡@@Its_Shaun_the_Sheep

[@Flexy59]

​@@Its_Shaun_the_Sheepstole my joke 😭😂

[@LanceHall]

Thank you so much for doing this work and making it concise and understandable for people who don't know (and those that do). It's SO important people have access to basic geology information so they won't be misled. Short videos with nice graphics like this are the best when trying to explain something and sharing on social media and forums. Other people make one hour and two hour long videos and you'll never get lay people and Geology skeptics to watch those.

[@LanceHall]

I've been an active fossil hunter for 20 years in the Fort Worth, Texas area (Cretaceous/Paleozoic layers) and I have yet to find anything that conflicts with the standard Geologic Column. I find the same things in the same order and in the same layers the original Texas geologists documented 150 years ago. There are no "out of place" fossils from what I have observed locally. If someone found a trilobite bearing layer in Cretaceous strata or mammal bearing layer in Paleozoic strata every local geologist, paleontologist and even rock clubs would rush to that locality. It would make the news and be published on.

[@GeoGolfer]

That is very similar to saying “I have yet to find a place where gravity doesn’t exist “.

[@michjefferson77]

wow must be fun😃

[@jeremysmith4620]

I tried dating the Earth once, but it just didn't work out. It was really the age difference, like we were from different eras. She was Precambrian and I was Cenozoic. we parted on good terms, but I'll never forget her hips. That 43 kilometer flare out always got me even hotter that the equator.

[@SirHenryHenson]

Video didn't help. She said she's only interested in a Pluto-nic relationship... I'll see myself out.

[@exhumus]

You shoul've Sat urn this one a bit longer before Ju pit er out there. It would've given you a chance to Nep-tune it for more Ext-Uran(e)us laughs and really come off as a Mars-ter.

[@hadhad69]

This is excellent I have watched a lot of geology videos but was missing some of this basic knowledge. It's illuminated the field for me even more, look forward to the rest of the series!

[@ScottBub]

One thing that creationists try to do is say that when geologists point to fossils to gauge how old rocks are they are using a circular Reasoning fallacy saying that the rocks tell how old the fossils are and the fossils tell how old the rocks are. Can you also do a simple explanation of why this isn’t the case in your next video of this series of it fits the script?

[@magicrectangleEnt]

I thought that was kind of addressed in this video? The video goes into several ways that a rock’s age can be told, and only includes “by the age of the fossils it contains” as a single method from that list. Since there are other ways given as to how we can tell the age of a rock, doesn’t that negate the initial circular reasoning complaint that a creationist might have?

[@Sampsonoff]

@@magicrectangleEntok but that would require watching the video 🤷‍♂️😂

[@ScottBub]

@realrunujhkj I agree that he talked about radiometric dating, but he was also talking about two different types of dating. One of which was relative dating. So, I thought that it would be important to point out that even in relative dating it's not a circular problem.

[@ScottBub]

@@Sampsonoff Are you saying that I didn't watch the video or it wouldn't be something he should put in the video because creationists wouldn't watch it to begin with? Because I watched the video and am not a creationist.

[@Sampsonoff]

@@ScottBub actually I’m the worst sort of person; I didn’t even watch the video

[@maciok4368]

I dont think u should be dating relatives

[@mikhailquashie9899]

Thank you for another informative video on the Geology Series @ProfessorDaveExplains!!!

[@user-qh9oj8qj7z]

I don't know how he does it but he makes learning Geology so much better and so much enjoyable!!!!!

[@fakepng1]

Thank you, once again, Professor. I can now understand lessons I couldn't with my smaller brain. Now I have a better sense of things

[@goodboi6540]

I genuinely thought this was going to be a joke video about dating the earth

[@aagereinertjakobsen4832]

Relative Dating is what they call a good old time in Alabama.

[@freddan6fly]

Isn't that incest?

[@vedantbhard]

@@freddan6fly that's the joke

[@nunya_bizniz]

🤣👍

[@Thirdbase9]

That's what family reunions are for.

[@haggismcbaggis9485]

My auntie said I could marry my 2nd cousin because we weren't blood related.

[@PavewayIII-gbu24]

Another banger video but all these comments got me wanting you to do a video on dating strategies; your personality would make that topic very amusing

[@SlicedZucchini]

thank you for explaining things! Call me silly but I actually thought the headline was referring to like relationship dating, so I was like, have common interests and goals with the earth haha

[@spankflaps1365]

First date with the Earth, I took her to the movies.

[@joshuathrasher9581]

Every time i date the earth she always catches me staring at the sky Love you dude have a good one 🤙

[@Cloveis]

We love you Dave, thank you for being such a good educator

[@NC_Isro_64]

Yes i totally agree

[@glennpearson9348]

The last time I read a book on the Principle of Relative Dating its cover was a genealogical depiction of a family in Tennessee.

[@killgriffinnow]

Relative dating…SWEET HOME ALABAMA!

[@tassimo9995]

the earth has always been my biggest crush, thx dave

[@agustinfranco0]

i tried giving her flowers, she said she already had lots of those...

[@markusbaker1161]

I read the title all wrong for this video! Great content Dave 😊

[@sneha10010]

Good! David it was actually helpful 😄

[@v4603]

movie and a nice meal always did the trick when the earth and i were still together

[@MotoGiant]

great job!

[@spitfire3311]

We gettin relative with it fellas

[@davidfitnesstech]

Love all the videos Dave. And the cherry on top, is that creationists will hate it ;-) And will most likely warn their congregations not to watch it.

[@agustinfranco0]

i swear, you need to fuse with Kursgesagt, their animation with your explanations would be the best thing humanity has ever made.

[@GeoGolfer]

About unconformities, you missed on structural un conformity which happens when a sequence is faulted and stacked on another sequence. As seen commonly with thrust faults

[@jamiegallier2106]

Thank you!

[@matherman1111]

Im too nervous to ask her out. Any tips on what i should do?

[@anthroponacious]

Relative dating is illegal in every state but 2.

[@fazergazer]

Hey Earth, I want a date. Can I have your number? 😂

[@sciencenerd7639]

thank you

[@davidsmith7653]

I'd been told that relative dating was a no-no but my cousin is hot and you make it sound so easy. I'm off to buy flowers.

[@FlyingSpaghettiJesus]

But muh book says things!

[@KoRntech]

Oh I can hear the Hovind hive minds groaning. 😅

[@thekwjiboo]

I swear to Gilgamesh I'll have a stroke the next time I hear a YEC say "you date the rocks by the fossils and the fossils by the rocks? Haha that's dumb, clearly Earth is 6,000 years old!".

[@Dunger974]

Kent hovind will still say the earth doesn’t have a time stamp

[@LanceHall]

He's the dumbest of all the YECs.

[@freddan6fly]

Well Kent the inmate always lies so that is that.

[@dogwalker666]

IF Kent's lips move he is lying.

[@Dunger974]

@@freddan6fly no shit lol

[@RealJiffyCones]

Look, earth is nice and all, but the age gap is a little too big between us, and I don't think the relationship would work out.

[@ChrisPierreBacon]

Thanks Dave, i was worried my cousin wouldn't be into me, but you've really boosted my Alabama confidence!

[@mikhailquashie9899]

I will be starting my Bachelor’s in Geology come Spring. I wanted to know if anyone had tips for me to be the one of the top students if not the #1 throughout my college degree?

[@publiozinj4882]

Be a female and minority.

[@tornadomash00]

probably the same requirements as graduating top of your class in highschool, just study hard, turn in assignments and (if your professor/college allows it) do makeups for things you missed

[@mikhailquashie9899]

@@tornadomash00 I wasted a lot of time in high school. In hindsight, I see now what must be done and what must change to better or to be the best. I can’t wait to start the journey and correct my past mistakes that held me back.

[@kylezo]

Relative dating is still legal in much of the bible belt.

[@Kyeudo]

Correlation or causation? You decide!

[@krisironcastle3178]

Hedean is rarely referred to as an Eon. we just say Precambrian when it comes to anything before the phanerozoic.

[@ProfessorDaveExplains]

That is not accurate. Start this geology series from the beginning.

[@krisironcastle3178]

There is no reason to divide the Eons like that when simply referring to them. Just follow the GSA terminology that classifies the Eons as Precambrian and Phanerozoic. @@ProfessorDaveExplains

[@haven216]

As Dave said, this isn't accurate. The Precambrian is formally subdivided into the Proterozoic, Archean, and Hadean eons.

[@krisironcastle3178]

I cited the GSA terminology. The Geological time is dived into two Eons, the Precambrian and the Phanerozoic. Dave literally just googled "geological time scale" and used a random image. Just use Science Direct next time if you want to do a presentation.@@haven216

[@12carbon]

​@@krisironcastle3178"Precambrian" is not even a formal term. It should only be used when focusing exclusively on the Phanerozoic and making a reference to the time span before it.

[@AshwaniKumar-tx3cq]

I request you to increase frequency of uploading lectures

[@ProfessorDaveExplains]

I post three times a week, chief. That's pretty much unheard of for someone who runs this type of channel by themselves.

[@AshwaniKumar-tx3cq]

@@ProfessorDaveExplains Thank you. But, I was referring to geology series😊. Anyhow, I've huge respect for you who can run single handedly such a big initiative. 🙏🙏🙏❤️

[@ericvulgate]

O I assumed this would be about pick up lines

[@ErrantMasa]

This makes me wish WildwoodClaire1 was still making videos...

[@AlbertaGeek]

Truly a legend from the earlier days of KZbin.

[@ErrantMasa]

@@AlbertaGeek her main chew-toy NephilimFree pals around with Darth Dawkins these days

[@AlbertaGeek]

@@ErrantMasa How bizarre.

[@ErrantMasa]

@@AlbertaGeek indeed. and Nephy also crosses over into another circle of lunacy via this one wackjob known as G Man, infamous for ringing Matt Dillahunty late at night

[@lukemoisant3917]

Good video Dave, I am a Christian myself and have disagreements with you on origin of life, however your videos are very useful and you seem like a decent guy. This is useful for me in arguing against young earth creationism that some Christian friends of mine believe in and which I am definitely not a fan of.

[@chbu7081]

Dating, rocks.

[@nowhereboy]

Negatron approves this video.

[@jojolopez5234]

Nice

[@donchristie420]

Stay safe Wa el

[@waelfadlallah8939]

Thanks man, i know i am late 😅

[@ythegameritaisthebest]

I thought you meant how to take the earth on a date

[@AlbertaGeek]

Wow, what an original joke!

[@ythegameritaisthebest]

@@AlbertaGeek I did think that tho

[@benjaminkoch2380]

"relative dating" out of context is weird

[@KrytoRift]

Dating thr ENTIRE earth? That seems exhausting

[@manuell3505]

All sides are probably of roughly the same age...

[@JesterSatans]

I hope to find some cross-bedding while out dating.

[@pramodsingh7569]

❤❤ from 🇮🇳

[@Rkenton48]

Oh... I thought you would ask her out for coffee or something, my bad.

[@Frankkk793]

My lonely ass thought this was a guide on how to date on Earth

[@SkinkUA]

romantic dating

[@Gandhi_Physique]

I'll spare you in repeating the same joke over and over again. I never really thought about how rocks could move over time and that would cause issue with dating. I really wish I could see what Earth was doing in a timelapse, just to witness more of the sheer power of Earth's natural phenomena. Talking about sedimentary rock though, say 100 million years goes by. Will the dirt I see today eventually get covered and compressed into some sort of rock, or is that sort of possible but way more complicated?

[@antongomez4336]

so it's definitely most likely not 6000 years old right?

[@adriana-istrate]

There are even human civilizations older than that, e.g. Sumerians.

[@AlbertaGeek]

@@adriana-istrate OP was making a funny.

[@nowhereboy]

I have socks older than that.

[@alicem9582]

Step 1: Ask her on a date

[@ZenBearV13]

I’m pretty sure Relative Dating is illegal in most states.

[@rbfailomkyodn4537]

Furst

[@Ewgene]

This is the weirdest dating advice I've ever had

[@MarcPagan]

"When I go in for a physical, they no longer ask me how old I am, ...they just carbon date me." Ronald Reagan

[@timonhallas2709]

Ha! Never heard that one.

[@kefhomepage]

Im not sure you can date , your relative, distant ones ok i guess

[@cdpalmo]

might as well just date the earth atp

[@jeremyhofmann7034]

Date her? I hardly know her

[@EricBurns1]

Grab popcorn here before you start seeing creationists' comments

[@kekchanbiggestfan]

Ok now do a video on how to get to second base

[@taherbertolinirodrigues9104]

First off you gotta offer her some chocolate or something, show her that you care

[@jamesczekalski9349]

I read the title and thought this was some sexual kink... The Internet has ruined me

[@johnsonfitzgerald2696]

Your flat earth friends pioneered and strongly endorse relative dating

[@Forest_Fifer]

Relative dating. Or, the contents of the Book of Genesis, as its also known.

[@TheDarkSide11891]

No you’re talking about absolute dating. Absolutely wrong, that is.

[@Katy_Jones]

@@TheDarkSide11891 Definitively wrong?

[@publiozinj4882]

And which rock formation are the result of the book of Genesis? Explain it all. I'm listening. And when you're done, you can explain to the geologic community that they have it all wrong.

[@Forest_Fifer]

@@publiozinj4882 r/whoosh

[@Kyeudo]

@@publiozinj4882 It's a joke about inbreeding.

[@dominiclester3232]

It may not bother you but 99% of your U.K. fans will stop listening at “horizontality” because it’s not a word any of us are familiar with. I’d call it an Americanism, a bit like “dove” which we never use in place of dived...Probably not a big deal, but strata already has enough unnecessarily long words!

[@alanthompson8515]

Not so. Google: Nicolas Steno (1838 -1686). He was Dane working in Italy a long time before any Americanisms were able to develop. His De Solido was in Latin and the word he used was horizontalis.

[@dominiclester3232]

@@alanthompson8515 Bizarre comment! If you are English you will know exactly what I mean. I was polite and I was genuinely distracted by the word which is not in the Cambridge dictionary.

[@GeoGolfer]

Very commonly used in geology across the globe.

[@alanthompson8515]

@@dominiclester3232 Your comment was strange (hence my effort to respond) but hardly bizarre. I was just pointing out that your ignorance of the word, and especially your thought that it was somehow an "americanism" is not shared

[@alanthompson8515]

​@@GeoGolfer Agreed. Also in KZbin Geology videos.

[@planetpeterson2824]

Imagine thinking layers of completely different composition were deposited slowly overtime instead of during the worldwide cataclysm 4000 years ago 🤡🤡🤡

[@ProfessorDaveExplains]

I mean, are you being sarcastic or are you genuinely this stupid?

[@dogwalker666]

Hope you are joking otherwise you need professional help.

[@nunya_bizniz]

​@@ProfessorDaveExplainshe's joking, sir. He also debunks flattards and young earth creationists.

[@NinjaMonkeyPrime]

Maybe try /s to avoid poe's law

[@planetpeterson2824]

@@NinjaMonkeyPrime Your inability to see the obvious is your failing, not mine

[@colorlesscircle5743]

Why do you complicate it so much when you can just say "god did it" and be done with it? I mean come on. We got more important things to do. Like praying to god. I don't really know about what. We can't just ask him to stop the war because.. isn't that a part of his "greater plan?" It seems kinda arrogant to interfere with god's plans, doesn't it? Then the same goes with all other things.. the disasters, the plagues, the poor and crippled, it feels futile. But we can do so many other things! Or... hmm... I don't know, we could collect stamps? I have four. Well, they are all the same and I have to use two today, but would someone like to trade one? I specifically need the one from Northern Sentinel Island for my collection. Viva la god or something, science bad because not in bible. Checkmate atheists

[@Gandhi_Physique]

Why did you even write this lol.

[@colorlesscircle5743]

@@Gandhi_Physique I was sitting constipated on the loo and I needed some inspiration, so I tried to put myself into the shoes of a religious flat earther. It worked! So, you don't have any stamps to trade, I take it?

[@Gandhi_Physique]

@@colorlesscircle5743 Okay, interesting. I don't collect stamps, so nah. Hopefully you feel better now lol.

[@colorlesscircle5743]

@@Gandhi_Physique I do feel better, thank you. You should get some stamps, man.

[@Gandhi_Physique]

@@colorlesscircle5743 I prefer coins and electronics myself, stamps just aren't that interesting to me tbh. I do like stickers though.