An Overview of Earth’s Layers 

Man, I just love this series. Somewhere along the way in my college education, decades ago, I had to make a choice about what I wanted to study. I ultimately decided on civil engineering, but I had so much interest in geology that I used most of my elective courses on topics like this. Looking forward to the next installment which will, no doubt, cover P-waves and S-waves and how we used seismic events on one side of the planet to better understand the deepest reaches of our planet from the other side. Great work, Professor Dave!

I always imagined that the subducting plate was being pushed under the overriding plate instead of pulled. That never jived with how those splits look in the oceanic crust where new material is being exposed. This makes sense now.

In these tutorials I especially love that you don't shy away from dumping a lot of information at once, since everyone can watch the video multiple times and review. This is very informative and condensed, and at the same time accessible even if you only half-remember high school introduction to geology.

Very good explanation! i spent 33 years in the mining industry as a mining geo and a Senior Engineer. Most recently at a project/mine owned by Sibanye/Stillwater her in southern Montana. Our deposit is a VERY old Intrusive unit that was uplifted during the Beartooth mountain uplift. Our deposits are dated at 1.2 Billion years old (yes, 9 zeros). Never got subducted again. Uplifted over MUCH younger Limestone unit. We mine Platinum and Palladium. We mine a little "sliver" of the entire original magma settlement. Just 1 corner (0.001%). but still our mine life is 50+ years that we know of. If you ever want an underground tour, you're more than welcome!

The illustrations are wonderful. Very informative and yet have an artful elegance to them.

This was an awesome update to my high-school sophomore "Earth Science" class. Thanks, Dave!

I cannot thank you enough for this video. My young son was asking me about what caused volcanos and I was not able to articulate it well. We watched this together and paused whenever he needed to study the image. He even correct his uncle when they talked about lava vs magma which made me so proud as we had talked about it after your video. Thank you as always Professor Dave.

I believe there's a pretty big facility in the UK where they have a machine that simulates magnetosphere generation with a large sphere of molten metal. They've found that the magnetic field can appear spontaneously

Professor Dave you always make science interesting please keep on going with the thing you do

Science and learning is awesome!

The Geodynamo has to be the coolest thing I've ever heard. Metal af

okay I got a weird question how do we know what the earths core looks like? Also how do we know what its made out of? Also love the content Prof. Dave Started with u roasting conspiracy stood for learning about cool new stuff and going back to school to learn physics

This was absolutely fascinating. I knew some of this but by far, not all of it.

I have often wondered the effect Theia slamming into Earth was the beginning of forming plates on the Earths crust.

Beautiful presentation Professor Dave❤

Amazing depth in this lesson.

So, what you're REALLY saying is, watching the movie "The Core" was not enough in and of itself to get my PHD?

Flat earthers should watch this LMAO

You are amazing Professor Dave! This is one of the best videos I've seen about the layers of the Earth!

Its really help to my science subject thank you

These videos are bringing me back to my historical geology days in college. Was my favorite class I took and love these summary videos!

I love this channel; it's pretty nice to check back here every few days or weeks to refresh my knowledge on some interesting subjects

Dude i love your channel. I never took education seriously when i was young. Planning on going back, nice!

This is super fascinating. Takes me back to college geology.

Before I begin my actual comment... Before I begin my actual comment, I would like to apologize in advance for my inadequate level of English proficiency. I am not a native speaker of the world's current lingua franca which unfortunately leads to me making numerous embarrassing mistakes being made whenever I attempt to communicate using this language. Whenever I am reminded of how I lack the ability to convey my thoughts in an eloquent manner, I feel as though I have committed a cardinal sin, as though every English teacher in the world is simultaneously shaking their head and sighing due to how utterly disappointed they are at me. Although I know that saying sorry to those of you who are reading my comment will not change the fact that I fail miserably to write and speak perfect English, I am writing this as a way to deter a certain type of people who cannot stand poor English from mocking me by posting unwanted and unnecessary comments detailing my every blunder although you may be angry or made at me. so please don't. Here is the comment i wanted to make: first.

You have better teaching skills Than my professor

One thing I didn't understand though. I think you mentioned that the inner core is rotating faster than the crust/mantel and then explained that it was due to the magnetic field, similar to an induction motor. But induction motors always spin SLOWER than the magnetic field. This is a necessary part of how they work. If the rotor was spinning faster, the induced currents and field interactions would apply torques in the opposite direction, slowing the rotor down. (for example a magnetic field in an induction motor stator might rotate 1800 RPM, but the rotor will spin at 1780 RPM) So, how does the magnetic field make the inner core spin FASTER???

YO sir Dave Do i get a hi Massive fan 🙂

Ah Dave! Love your videos.

Dave, it's like you're not even trying: what about middle of Earth and the mole people? Get it together. But seriously, are magnetic reversals fast in people time or on the geological time scale and more of a gradual thing?

I was looking for a detailed explanation and I found it lol. I didn't think it would be so in depth that most of it went over my head tho lol, still an awesome video! My Thanks

Ok, I'll be the idiot to ask. @5:34 why does the geo dynamo need a seed? Thanks

Thank you Professor Dave.

thanks for making these videos

Nice work, Dave!!! David

I'm watching this because I misread the title as: "An overview of Earth's Lawyers"

This is fascinating, thank-you!

Hi, just to complement the info. You can read about the Fragment-Asperity model. It explains earthquakes using a physics model point of view. Using Tsallis entropy! I love your videos!

at around 8:50 you say that the inner core grows by a rate of 1 millimeter per year, but is that an increase in radius of 1mm, or an increase in diameter of 1mm?

There's no rule that oceanic crust has to be under sea right? I wonder how it would look like above the surface.

Heya. I'm a Geophysist, worth noting that we can image and see some these layers both by mapping and inverting the travel time of earthquakes but also observed with reflected seismic data. We can map for example the crust-mantle boundary across the earth's continental margins.

Thanks, Dave!

As usual, the energy source of the Earth's heat got glossed over with a generalized radiogenic heat. There seems to be a great variability in geological activity within the Earth. Flood basalts and super volcanos come to mind. My thought is that there is probably nuclear fission naturally occurring deep in the Earth creating significant heat. Natural fission is variable in output as the parameters of the critical mass change. This is all probably true but geologic science does not say so or explore the concept. I think its moving at geologic speed.

Basically the oceanic crust, as it pushes underneath the continental crust, turns back into molten rock. And If I'm not mistaken, it's a continuous cycle as the mantle and circulates with the outer core and creates convection just like a lava lamp, as Professor Dave explained. Man, I really enjoy brain food.

I've already known this stuff a long time but I would listen to this guy read the phonebook, I enjoy his voice do much. He's not a deep-voiced Morgan Freeman type, but still, I really like it! Great to fall asleep, to, as well!

how long does it take for the oceanic slabs to heat up in the mantle like could we have bacteria or even complex life just vibing in a closed cave in the middle of the mantle

Always loved your videos and presentations Professor Dave. And I especially love your debates, I've used some of your points to argue against Flat Earthers a few times. Would you mind me asking if you'll ever do any kind of Live debate again, or would you prefer to move onto something a little more calm?

With the scientific methods you use in your videos can you produce a video on ghosts & the supernatural. It would be really interesting to see your take on the subject using sciences.

Thank you: Really grand. 🌍👍

Dave could you do one on the Sun? Or maybe you have already? Fascinating stuff thanks.

The more I learn how lucky we are, taking all these variables in account it’s almost certain we are an anomaly at best.

So do i stop real quick and learn about electronical engineering so i can learn about geodynamo?

Curious if the flat earthers will jump on the mention of buoyancy.

I've only heard of the D' ' layer in a critique about how geologists need to come up with better names.

In no way these layers magically came together and formed earth. This is well designed intelligent designed with purpose.

I'm tackling a bachelor's degree in biology and geology in early September, and this man is a hero! All hail Professor Dave Farina, Holy Slayer of Ignorance! EDIT: Well, it turns out I couldn't solve my illiteracy in mathematics and thus had to abort the whole project. Oh well. At least I can still enjoy science thanks to RU-vid channels such as this one!

So the earth is basically one giant onion?

An overview of the underview!

Hey professor dave, will you ever make a philosophy playlist?

Here is something I don't understand. If the heavier materials sank when the Earth was entirely molten, then why are there heavy elements near the surface which can be mined?

Hay Dave I love your videos but I was wondering if you could do a video of a metal that’s apparently as strong as diamonds it’s called platinum gold

I am in class watching this

good stuff. however i am very dissapointed to learn that i am going to not be able to celebrate my 92nd billionth birthday on earth

Radiogenic heat, wooo!!!!

How thick is the crust on our pizza earth? Rotfl

Hi Dave

btw: its debated if the collision and absorbtion of theia played a huge part in injecting additional heat and core material into earth, and thus we can enjoy a magnetic field still, while all other rocky planets in the solar system are magnetically dead, as they did not have this injection of heat and core material. their cores are already too solid and cant produce such a life saving field anymore....

Dave, sir, I have a question regarding homeopathy. It stems from a video you put out 4/3/19 titled "astrology: fact or fiction". I'm a bachelor-degree-level nurse, and I believe in science. However pseudoscience can be helpful in some cases. For instance, aloe vera does seem to heal burns and wounds as quickly as medicinal ointments. Certain homeopathic remedies do help to control blood pressure and regulate cholesterol and blood sugar. Although these are homeopathic, they are also widely used. Do these remedies ever get accepted by true science?

can you check out terryology

Hey Dave have you ever considered making a video about the moon landing? I’ve been seeing that topic pop up a lot lately, amongst (most predictably) flat-Earthers. Oh, and I’m also seeing denial that nuclear bombs exist as well… that Hiroshima and Nagasaki were just standard incendiaries-like Dresden-and Chernobyl was apparently just a hoax 😂

so its like onion

How it works on the Flatearth model?

❤❤❤❤

🎉🎉

Where’s the hollow earth?

Onelove

Diehold foundation!!!! Lqtm

The earth is filled with layers, like an onion

Can SOMEONE please explain "HOW" do we know about these layers, since we've never dug even half way of the first layer!? Or shall we just believe because "it's science"?

JESUS CHRIST IS KING 👑✝️

❤️👏👍

Any flat earthers in here ? 😂😂

Bro you sound American why’re you using kilometers

It's all scripted for you by subject matter experts right?

Ok n...Read more

Earth is basically just a big ball of lava

Interestingly, I have read about oil drilling, & in the Alaskan oil fields between 1,100ft & 1,700ft down there is perfectly preserved ancient tropical forests. They are frozen, not petrified. Oil drillers have pulled up many palm trees, ferns, pine cones, & other frozen tropical forms of life in the Alaskan oil fields. Scientists have studied this, but its not information given to the general public, except in a few books. They also say that oil is the 2nd most abundant liquid on Earth, & not from dinos. 'Oil shortages' are complete BS created by TPTB.

1hrlate births cros

At the risk of committing a dad joke: Mother Earth really is a multi-layered character, huh? You're welcome.

I'm sorry but your pronunciation of "peridotite" is driving me crazy. It's actually pronounced "peri-dough-tight." Additionally, the rock shown consisting mainly of olivine is likely dunite named for Dun Mountain in New Zealand. The only addition I'd make to the presentation is that there are melts of intermediate chemistry between high silica felsic and low silica (ultra)mafic rocks. The Andes Mountains are a prime example of an intermediate composition. The amount of silica affects the viscosity of a melt that directly determines the kind of volcanic eruption might occur. High silica results in trapped gasses and water vapor resulting in an explosive eruption like Mt St Helens vs a runny lava like in Hawaii. Then you could get into that sexy Bowen's Reaction Series. But I'm just a nerd that taught that so it's my bias. But as always, great presentation and completely on point. It's always a good day when you know that folks are being presented with accurate information and getting educated. As we'd say in the Navy, "Bravo Zulu!'

make some videos about the what scientists have discovered inside of other planetary bodies. Inside of gas giant planets the idea that gasses like hydrogen can be compressed into a metal like substance is mind blowing

Do we know how long a pole-reversal process takes? When it's said we may be due for one, does that mean that it flips near instantly (over a few days or year), or over a few hundred years (also geologically "instantly"), or over a much longer time?

so diamonds aren't from y level 16 after all

What are you doing with the $1m dollars you were given to hide that the earth is flat? This is sarcasm by the way. Even though it sounds completely ridiculous there are people as you well know that believe this.

The power of such a good summary. Thank you very much, this video clarified a lot for me.

@ProfessorDaveExplains make immunology

Gret video, Professor Dav. I look forward to the next lecture. Geology (esp. marine geology), violcanology, and seismology being three fields of interest.

Will there be a video on the giant underwater oceans, like under africa(I think)

nice!