Stable Oxygen Isotopes & Paleoclimate Proxies | GEO GIRL

[@alieward4142]

Aaaaah thank you so much for the Ologies shout out! Great video! Dadward approved. 👍

[@GEOGIRL]

OMG!!! I can't believe you actually saw this! Thanks for commenting! I am so obsessed with Ologies! Thank you so much for everything you do for science, seriously! Keep Ologies going forever please!

[@barbaradurfee645]

@@GEOGIRL Mom Geo Girl approved!!

[@bestfootballtv293]

i have a carbonaceous meteorite i wanna do isotope oxygen ,how can i do that.

[@abdullahfarhat9848]

You're more beautiful than your isotopes, I guess. Right?

[@stevengill1736]

Gosh, I never thought of the fact that isotope concentrations are going to be parametrically pumped in various ways! Pretty cool! Now I see how simple physical processes can concentrate or rarify element isotopes in predictable ways, as you demonstrated with CaCO3 in lifeforms with variable oxygen isotope concentrations - bravo! Can't wait to watch the videos on strontium and sulfur, and the rest - thank you kindly!

[@MrMjamm]

Great video! I was looking for this sort of repetition of stuff I learned 15 years ago at the University. Thank you very much. Please continue! :)

[@GEOGIRL]

Thanks so much for the comment, so glad you found it helpful :D will do ;)

[@a.randomjack6661]

I'm a year late, but left a 👍, Although, it deserves at least 5. I used to think black holes were fascinating... Paleoclimatology is mind blowing.

[@GEOGIRL]

Agreed! Paleoclimatology is so cool :D

[@DavidAmrod]

A font of knowledge, you are! I have watched this video 3x, and I am still learning new things!!

[@GEOGIRL]

Oh wow that is so good to hear considering this was one of my early (and not so well produced) videos haha, thank you so much! ;)

[@DavidAmrod]

@@GEOGIRL You are very welcome! It was excellent. Just because you have improved with time takes away none of the merit of this video. Smiles.

[@PlayNowWorkLater]

I’m a big fan of science. I understand it, and can follow it. And even though Oxygen isotopes is not my main field of study I can still follow the logic. Where I’m going with this is that I have met lots of people who aren’t fans of science, or in the least aren’t patient enough to follow the logic you’re presenting here. And while climate deniers drive me crazy, I can at least empathize with not being presented something that is (for the lack of a better way of saying this), it needs to be “dumbed down” for certain audiences. I think it’s important for those who are able to explain it to differ audiences to take the reigns and do so. I think it was Einstein that said “If you can’t explain it to a 6 year old, then you don’t really understand yourself.” Probably paraphrasing a bit. Anyways I love the “Ask smart people, stupid questions” that you’re going with here, but I think it can be taken One step further. “Plant seeds that allow ideas to grow”. It’s how I teach. And this topic is one I think can be broken down. Made more entertaining or digestible for a wider audience. That said, I personally love what you present. And your channel. I just frustrated with the people who come across this, and are presented with an opportunity to learn, but swipe up and move on to something that is easier and probably less accurate.

[@GEOGIRL]

I couldn't agree more! I actually made this video so long ago back when I thought my channel was only going to be watched by college students trying to pass an exam. Now I am (I think) much better at teaching to a broader audience. I still keep the information relatively advanced most times, but I think I am getting better at being more inclusive to lay audiences in my more recent videos. I agree that this is a super important aspect of good science communication and teaching. I will always continue to work on this moving forward. Thanks for sharing your thoughts! ;)

[@PlayNowWorkLater]

@@GEOGIRL yes. Definitely you are reaching a wide audience. Obviously. You have a lot of followers. I didn’t think to look at this video age. Sorry, if I’m coming across as frustrated. I try to educate people on my own way. Though I’m new to it with the whole KZbin way. I just think isotopes are a great way to educate people about SOOOO much in science that is misunderstood. I’ve searched KZbin for accessible videos on isotopes with lots of views. Veritasium has one. But again, it doesn’t take what is learned and bring it that extra step. I’m thinking RadioCarbon dating and Oxygen isotopes analysis with climate change. Two pretty big topics that there is a lot of ignorance on. Climate deniers. And age of the earth deniers. Anyways, appreciate your ear. And thanks for doing what you do.

[@jadefinchscene5644]

it is fantastic when a concept clicks into place and a level of understanding is increased. great explanation of fractionization and excellent choice of example using oxygen and ice. so many things suddenly make so much more sense.

[@GEOGIRL]

So glad you found it helpful! Thank you for the comment ;D

[@robhumphreys7952]

Absolutely fantastic . All your videos have just gripped me. Thanks Geo Girl.

[@GEOGIRL]

Thanks for the comment and kind words! So glad you have been enjoying my videos! If there are ever any topics I haven't covered that you'd like me to discuss let me know! ;D

[@ABDULLAH-yr6xc]

Easy to understand and the words you used in the video are now my notes😅

[@kira_draws_and_digs]

Thanks for video! Can you spell what kind of podcast you were talking about in the beginning? I can't get it.

[@GEOGIRL]

Sure, it is the Ologies podcast! It is hosted by Alie Ward, and she does amazing, I highly recommend ;D

[@josiadam987]

Thank you so much!! I am taking the class prehistoric anthropology in university right now, you explain this stuff soooo good!

[@GEOGIRL]

So glad you found this video helpful! Best of luck with your class, and let me know if you ever have topic suggestions for my future videos ;)

[@robinleow185]

Super brilliant parting words! 🤓

[@AnzorMahammatov]

Tank you so much for helpful video!I'm ekogeochemistrst! I'm interested in heavy metalls . Can you help me

[@KerriEverlasting]

I really don't get isotopes. I guess it's because I don't know chemistry. All those random numbers and circles seem to make zero sense in my brain. Grr. Do you have a video that would be good to watch with atom background type stuff so I can understand this better?

[@GEOGIRL]

No, it's my fault Kerri, I made my isotope videos a long time ago, before I got better at explaining things from the beginning. I believe I have a very old video that has a brief slide on what elements are vs isotopes and ions: kzbin.info/www/bejne/jHzKYntpprmFf68, but I hope to actually post another soon giving some background on isotopes because I really never have. Maybe something like "What are isotopes and how are they used in geology?"

[@leonderprofi420]

I just discovered this channel and i really like it. Great explanations and you provide sources! :D I think it could improve the video structure by putting the bonus information at the end a seperate video and maybe try to make less cuts.

[@GEOGIRL]

I am glad you find it helpful! Also, thanks so much for the suggestions! I started out making lectures for my students and was very new to this whole making and editing videos thing. I think my more recent videos are getting better, but I still have a lot to learn, so I appreciate the input :)

[@smileydaisy-qt3md]

Thank you so much! I have an exam coming up and I didn’t want to miss out on this topic. May i ask you what your PhD is in ? I m currently in the last year of my bachelors and i m really excited about palaeontology and palaeoclimatology.

[@GEOGIRL]

Mine is focused on paleoceanography & paleoclimatology! Specifically, I work on refining our understanding of how trace metals get preserved in the rock record so we can use them to reconstruct ancient oceanic/climatic conditions, like ocean pH, oxygen content, primary productivity (photosynthetic) rates, temperature, and more! :) It is the coolest thing ever! I think you'll love it :D Do you have any ideas of where you want to study for grad school?

[@noitalfed]

Your reference text appears to be graduate level and almost $400! Any more introductory suggestions at a more reasonable price for non -professionals?

[@bencydavid6089]

Thank you so much for the explanation, would love to see more videos on stable isotopes with tree ring proxy.

[@GEOGIRL]

Thanks for the topic suggestion! I plan to do many more stable isotope videos, so stay tuned! And I will work on another tree ring video too if you'd be interested in that :)

[@bencydavid6089]

@@GEOGIRL thank you:)

[@RosaFreitas-g2s]

Congratulations for such nice video. I am using gave it to my students at the university

[@caspasesumo]

Thank you :) Outstanding and highly informative presentation - as usual.

[@GEOGIRL]

Thanks! So glad you found it helpful :)

[@mab963]

I just discovered your channel and it is awesome! Hope you continue with many more cool videos!

[@GEOGIRL]

Thanks so much! I am glad you find it helpful! Will do😊

[@samuelkeller4745]

Thanks, I was going to ask how water temperature affects carbonate producing organisms but then you went and answered it! Will you be doing a video at all on the use of Barium as a proxy?

[@GEOGIRL]

Glad it was helpful! I hadn't thought about Barium, but it sounds super cool so I will definitely try to make one!

[@samuelkeller4745]

@@GEOGIRL www.sciencedirect.com/science/article/abs/pii/S0016703717300571

[@lemmerelassal2795]

Hi Geo Girl, how do you figure out the half life of C14? Where is a reproducible method to validate the half life of 5730 +- 40 years?

[@robertpierce1981]

I came here after watching “History of the Earth “ video talking about ancient earth and heavy oxygen. How do different forms of oxygen exist and what creates them? Would a heavy oxygen atmosphere support life?

[@GEOGIRL]

What a great question! For stable isotopes, technically nothing on Earth creates or destroys them. There was a set ratio of light and heavy stable oxygen isotopes in the supernova that our solar system formed from and since then these isotopes have been cycling through processes on Earth and becoming fractionated in ways I discussed in this video, but they are not becoming created or destroyed: when the ratio of heavy to light oxygen goes up in one oxygen reservoir it goes down in another because the entire heavy to light ratio of Earth's oxygen remains constant. That's why when we discuss oxygen isotope ratios of the past, we must define where the ratio came from (rainwater = atmospheric reservoir, marine carbonate material = ocean reservoir; when the atmospheric reservoir ratio increases the oceanic one decreases and vice versa-- there are other smaller reservoirs that might affect this, but this is the general trend). I do want to clarify, however, that I am only talking about STABLE isotopes here, RADIOACTIVE isotopes do decay (become destroyed) and RADIOGENIC isotopes (their decay products) do technically become 'created' but I talk about radioactive isotopes in other videos, here is a general overview if you're interested: As for the second question, yes, there is a set percentage of heavy oxygen in our atmosphere right now (yes it is a small percentage, but it is there), and humans and other animals don't typically discriminate between oxygen isotopes when respiring. So, I don't think it matters to life whether the atmospheric O2 is made of light or heavy oxygen isotopes or any mixture in between. :)

[@robertpierce1981]

@@GEOGIRL thank you very much.

[@wajdiallagui6057]

Are u sure about that I m already do my PhD in the carbon Isotope then the oxygen but I think there is other formations between them

[@GEOGIRL]

Hi there, not sure what you mean, or what question you are trying to ask. I want to help, do you mind reworded the question and asking again? Thanks! ;)

[@laurenmuller200]

Thank you, very helpful.

[@GEOGIRL]

Of course! So glad you found it helpful! :)

[@DevendraSingh-uy5ws]

Maam I have aquestion .. the del O-18 of forameniferal carbonate in a plistocene core changes from 2 0/00 at the bottom to -1 0/00 at the top .what sholud be the reason for this ?

[@GEOGIRL]

Are those values VPDB or VSMOW?

[@DevendraSingh-uy5ws]

@@GEOGIRL VSMOW

[@GEOGIRL]

​@@DevendraSingh-uy5ws Well it would indicate that the O isotope values are going from heavier to lighter values in that time range, but the reason may depend on how long a time range you are looking at. Because say you are only looking at a year, then these changes could be due to regular seasonal temperature fluctuations. However, if you are looking at the entire Pleistocene for example, and you see that the average goes down by about 3 permil through that time range, that could be due to a climatic shift from cooler to warmer climates. This would make sense because we were coming out of the LGM at the end of the Pleistocene. And throughout the entire period, there were major glacial-interglacial cycles that would've causes such climatic shifts. See my Holocene video for more on these Pleistocene glacial periods :) kzbin.info/www/bejne/Y4qqdWeMmNN-e7M

[@DevendraSingh-uy5ws]

@@GEOGIRL thank you, Ma'am, it's really helpful.

[@ronaldterieng9061]

Great video...thank you 👍

[@GEOGIRL]

Of course, glad you enjoyed it! ;)

[@ronaldterieng9061]

Can I get the ∆18O diagram that you used in your presentation? Would you mind sharing the link?

[@GEOGIRL]

@@ronaldterieng9061 Sure, here is the paper with the graph that goes all the way back to 60 million years ago: doi.org/10.1038/nature06588

[@ronaldterieng9061]

Thank you so much 🥰

[@junusavior65]

How accurate is the oxygen proxy in determining actual temperature? I understand that a change in oxygen isotope ratios might indicate a change in temperature, but how would you know the actual temperature it represents?

[@GEOGIRL]

Oh wow! That's not a question I can answer in a comment haha. It basically depends on A LOT of factors. For example, you have to take into account the material you are obtaining the ratio from (calcite, aragonite, water, etc.), the age of the sample, the location and depositional environment of the sample, what kind of organism if it is a fossil, the latitude of the sample at the time of formation as well as during its preservation, whether it represents marine or freshwater (atmospheric) oxygen source, the method you are using to obtain the oxygen isotope ratios, and I am sure I am missing some things, but these are the factors I remember having to be aware of when I was doing oxygen isotopes research. The good thing is, once you figure out these things, you just need to figure out how to express them mathematically and apply them to your raw oxygen isotope ratio data to obtain 'corrected' values that reflect all of this knowledge. Then once you have corrected values, you can see how much your data fluctuates and in what direction it fluctuates to get an idea of the temperature trend during the time your samples were deposited. OR you can try to get absolute temperature estimates by using modern correlations & models of oxygen isotope ratios with temperature values, but this may be less accurate and less useful than the relative (fluctuation) observations. Sorry it is kinda complicated, I hope this makes at least a little sense. (Also, if anyone is out there and does more oxygen isotope work than I do, please feel free to chime in if I missed anything or got something wrong, I am not expert, thanks!) :)

[@junusavior65]

@@GEOGIRL Thanks for the quick response! So the oxygen isotope proxy is really just used to determine fluctuation of temperature, not actual temperature. I have been pondering a lot recently on how we determine the actual temperature from thousands and millions of years ago. I have struggled on my search just using the internet alone. Is there a proxy we use that can tell us actual temperature? Or are all proxies just backdating temperature fluctuations from our current temperature readings? If you have a video on this forgive me, I have had trouble finding answers on these questions just searching on my own. If you don't know, would you be able to point me in the right direction? Again, thank you for any help.

[@GEOGIRL]

​@@junusavior65 Well I think it's not that oxygen isotopes can't be used to determine actual temperature in the past, it is just we most often do so by using multiple proxies just to double check our results, if that makes sense. For example, for marine environments that preserve fossils, we often reconstruct ancient temperature by using oxygen isotopes in conjunction with the types of marine fossils that are present in the same sediment. This can be very useful if the specific species can be identified (for example, microfossils like ostracods and foraminifera, or even macrofossils, like corals and certain types of mollusks, have very specific temperatures that they can tolerate), so with the species identified (or even genus or order) we can narrow down the temperature range quite a bit. We can also tell whether the sediment reflects that animals living environment because we know which species were benthic (lived on the sediment rather than in the water column) and we know that if they are preserved that the sediment hasn't gone through transport or diagenesis because carbonate fossils cannot withstand that very well. But fossils are just one more example, there are many other chemical and physical proxies we can use together we oxygen isotopes or even alone that reconstruct temperatures. With the use of all these proxies by different scientists on sediment around the globe, we have been able to reconstruct a pretty accurate picture of past temperatures by cross checking them with each other and the more they match the more robust our estimates become. I would say that going back until around 65 million years ago our estimates are very accurate and precise, then from 65 to 500 Ma, still pretty accurate but less precise, then before 500 Ma, accurate, but not very precise because we don't have many rocks that old to measure the chemistry of. Hope that all makes sense, if you want to see some examples of how we use many different proxies in conjunction to paint a picture of a past event, I would suggest watching either my GOE video (kzbin.info/www/bejne/gnyZiWZ7fKqXhbs) or snowball earth video (kzbin.info/www/bejne/g6u8qmyYer-hmNk), both discuss events that happened over 500 million years ago, but with the many lines of evidence in the rock record, we can paint a pretty accurate picture :)

[@junusavior65]

@@GEOGIRL Ok, I think I get it. So we calculate temperature from each proxy and then determine it's accuracy by comparing it to the temperatures we get from all of the other proxies together? Which in the end allows us to narrow the actual temperature range down as much as possible too? I apologize if that is basically what you said, it just helps me to summarize in my own words.

[@GEOGIRL]

@@junusavior65 Yes! You actually said it better than I did haha. But again, I want to stress that this is my understanding of how these proxies are used. I could very well be a bit off and it is best to check some recent publications before you trust me fully haha! ;)

[@pratyushkumar4439]

Plz.....ma'am give me any source upon marine isotope stage which will helpful for my seminar

[@GEOGIRL]

Sorry I am not sure what you mean by marine isotope stage? Could you specify? I would like to help ;)

[@ameydatye102]

grt video...keep it up

[@GEOGIRL]

Thanks! Glad you enjoyed it :)

[@CleberAssisUFPA]

Muito bom!

[@GEOGIRL]

Thank you, glad you enjoyed it! :D

[@lanetPulse101]

i dont think angels are in the haven some of them are in the earth too

[@agus2074]

Pintar..

[@johnnysystem2579]

Never make a time graph go to the left. They are simply to difficult to visualize. What your explaining is straightforward but then you complicate it with a badly made graph.

[@GEOGIRL]

I know, I didn't like that about the graph either, but I couldn't find one that went the other way. I will look harder for a different one next time. Thanks for the input!

[@johnnysystem2579]

@@GEOGIRL Thank you for responding. I wonder why some do this. The way we visualize data should be consistent but many graphs are not, Either way you cover the subjects well and you are easy to follow.

[@jeremytaylor9514]

Podcast ologies

[@GEOGIRL]

Yes! do you listen to it too? :D

[@mohsenalshagdari1686]

great, i will invite all friend in telegram channel here

[@GEOGIRL]

Thank you! Glad you liked it ;D