This is so interesting. Back in my geology courses in the early 80's my professors told us about the concept of "Suspect Terranes" and then told us that the area west of the Rockies was so complicated that no one understood it at all. It's great to know that we've been figuring out with the benefit of new tools what was once unknown.
Time Stamps: 00:00 Hellos and Thank Yous 17:57 Lecture Start 18:32 Previous Sessions 18:56 Future Sessions 19:53 Craton of North America 24:39 Terrane vs Terrain 27:52 Paper: Cordilleran suspect terranes 30:46 North American Craton Areas 33:00 Craton Additions 35:57 Where are the closest places to Ellensburg to see NA Craton? 37:12 Roadside Geology of Washington 38:20 Roadside Geology of the Northern Rockies 39:48 Exposed North American Craton 42:00 Supercontinents 43:32 1.8 billion years ago 44:59 Craton Boundary 45:59 How do we know the NA craton stops? 46:26 Platform Sedimentary Layers 46:52 Lithosphere Thickness 48:40 Seismic Line Across the Western Idaho Shear Zone 52:31 Strontium 0.706 Line 01:03:02 Shell Oil Darcell Well 01:06:25 Next Session Preview 01:08:55 Q&A 01:25:56 Toast and Goodbye
Hey boss, Nick From Home #47 Lahars is no longer available. I'm really disappointed because that was the last NFH I needed to see to catch up once I've seen this one. Love your content Nick, thanks for teaching me (and I guess everyone else) so much!
@@Ellensburg44 Hahaha, I appreciate the response Professor, but it's just a link to the same video that is unavailable. It says A+E Networks has blocked it on copyright grounds. It's okay, I know some stuff about lahars. I just like listening to you talk about anything.
Books mentioned or shown today (full list of Roadside Geology books see comment under Exotic B): Barry Lopez & Debra Gwartney: Homeground: Language for an American Landscape, revised edition, Trinity University Presa, 2011. Dave Tucker, Geology Underfoot in Western Washington, Mountain Press, 2015. David D. Alt & Donald W. Hyndman, Roadside Geology of the Northern Rockies, 1st edition, Mountain Press, 1972 (no long $3.95!) Also mentioned: Keith Heyer Meldahl, Hard Road West; History and Geology Along the Gold Rush Trail, university of Chicago Press, 2007. And our “textbook”: Marli Miller & Darrel Cowan Roadside Geology of Washington 2nd Ed., Mountain Press 2017. Also google search for Robert Hildebrand, Cratonic North America map Cordillaran Suspect Terranes by Peter J. Coney, David L. Jones, & James W. H. Monger , Nature, 288, 329-323, November 27, 1980.
I was really surprised to see the St line going down the crest of the Sierra. There's an absolute s-ton of volcanic/hydrothermic activity both old and current, on the eastern side. At the same time, it may have to do with the Sierra being lifted, so it may have poked through. I would have guessed the Whites/Inyo/Panamint chains. I found it fascinating, something to ponder!
By what point, I mean, when in time or under what criteria would we start to consider the new terranes old Craton. like maybe in 200 Ma from now or something? How I understand it is that the craton is made up of terranes that have come in at some point in history and eventually became craton at some point. Is that a correct understanding of it?
Maybe that difference in depth in the trench that bisects the WISZ has something to do with the Yellowstone hot spot. Seems to lead in the direction where Yellowstone is located today .
In an effort to impress Professor Nedard A. Zabalaba here is my Abstract: Exotic Terranes vs Cratons Laurentia, is a large continental craton that forms the ancient geological core of Eastern North America. Let’s associate the North American Continental Craton (NACC) as ‘hard candy’ chemically broadened into two groups: crystalline candies, generally smooth in appearance (chewy, hard caramels, toffees, and nougats), and amorphous candies, generally hard & brittle (Jaw Breakers, Atomic Fireballs, Jolly Rancher). In addition to Laurentia, we are adding the Deformed Craton of Western North America (DCWNA) to our terrain discussion of the North Western American Continent Basement Rock Study. Therefore we can describe the DCWNA as The Wyoming Craton forming the west-central United States and western Canada - more specifically, Montana, Wyoming, Utah, parts of Eastern Nevada, most of Idaho, Southern Alberta, Southern Saskatchewan, ( In an abstract description a large ‘peanut ‘brittle, semi-hard and crumbly, attached to the western ‘hard candy’). In conclusion, the DCWNA was attached to the NACC before our 200million year ago time frame by plate tectonic subduction
Regarding the Sr 87/86 ratio, Matt Jackson's Radiogenic Isotopes in the Earth's Mantle video gives a nice overview of what you're talking about. It's likely that many of your subscribers would find it interesting. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-8fPo91S3_FE.html
Nick, look at this paper: cires1.colorado.edu/people/jones.craig/WUStectonics/Hildebrand/Q6-1.html They discuss the Sr 0.706 "isopleth" (contour), and they find that it isn't a good demarcation of the North American craton.
I’m a simple carpenter but greatly enjoy learning about all of our pacific wonderland. True story, I hated geology as a child and now find it to be one of my favorite research projects
I found this series while it was still going three years ago - we had just moved from the east coast to Washington State. I loved this series and have stuck with you ever since. I'm currently participating in your Ice Age Floods A-Z series and have discovered that twice a week is not enough for me! So I'm re-watching this series and plan to re-watch Baja-BC series also! It's amazing how I see new things in these videos, even though I was with you three years ago when you originally led these sessions. I think my geography interest and knowledge have grown so much (plus all of the MANY field trips we've gone on to visit things you've pointed out in your sessions) and my grasp of the area has grown, I'm just *able* to hear new things in these sessions! I'm finding it just as exciting as the first time I watched.
Once upon a time, WA & OR smashed into NA. Is there still a collision happening along the WISZ? Or are they a VW Beetle flattened against the front of a semi-truck and carried along?
Thank you for posting this lecture it really helped me understand some of what I'm studying. Online is convenient but not always the easiest so your videos are much appreciated Professor
Not sure if this is relevant, however, i found it interesting. You can go as far back as 750 million years...its just like google earth dinosaurpictures.org/ancient-earth#240 .. you can zoom into your part of the globe to see varying dates, even enter your adress now and see where you would have lived way back when. Regards, Gleno From Australia.
Thanks, Gleno. That was fun, although the various views raised lots of questions that I can't answer. I too am from Australia, so I chose Melbourne as my location.
heres's a link that may help with the strontium ratios Nick is talking about.... so the '706 line' is a ratio between strontium (Sr) 87 & Sr 86...87/86=0.706 The western edge of Precambrian North America is mostly obscured by sedimentary cover. Its location is often inferred by a chemical indicator carried by magma as it samples the lithospheric mantle on its way up. The most commonly used indicator is uses Strontium, commonly called the Sr 0.706 line (initial 87Sr/86Sr = 0.706).
Nick I would like to join in the chats but I don't know what app to use. Glad that you left comments on! Mary I am the Mary that you responded to when I mentioned that I prefer a set schedule so I don't miss anything. Thanks. It's
I wasn’t aware of that strontium 706 line, so here’s some papers that popped up alluding to it, relating to identifying strike/slip faults: 1998 Wooden pubs.usgs.gov/of/1998/of98-338/chapters/chp04.pdf 2007 King geoscience.wisc.edu/icp-tims/wp-content/uploads/sites/5/2015/08/King_et_al_2007_Lithos.pdf 2008 Lackey: academic.oup.com/petrology/article/49/7/1397/1444040
Here's a nice article describing the meaning of the Sr ratios: www.ncbi.nlm.nih.gov/pmc/articles/PMC4996820/ The idea is that a Rubidium isotope decays into 87 Sr with a very long half-life, and looking at the ratio of 87 Sr to 86 Sr (a naturally-occurring stable isotope of strontium) yields a very long-duration "clock". The given ratio 0.706 refers to geology with roughly the same age.
ker·fuf·fle /kərˈfəfəl/ noun INFORMAL•BRITISH a commotion or fuss, especially one caused by conflicting views. "there was a kerfuffle over the chairmanship"
I have read about Professor Zenter in books regarding Cascadia and Juan De Facu. Happy that I have found him on RU-vid, giving a free university lessons on geology. God Bless.
It is so fun and familiar to see your livestreams going again! You have been a breath of fresh air during these strange days! You are like a knowledgeable neighbor! Cheers!
Fellow former 'Sconnie with an ISU grad degree (was Paul Link there 35 years ago?), enjoying these tremendously. I mostly work in soils over on that Great Plains orogeny block of the craton--fun to have a chance to learn a "story in the rocks" again!
earthquake.usgs.gov/earthquakes/map/?extent=-67.33986,-394.45313&extent=70.37785,-34.45313&baseLayer=terrain&list=false This is the link to the NSGS earthquake map I told some people about. It self-updates.
Three years on l wish there was somenody we jo could do this just as enga gu ingly for the North American Continent as a whole. From the early Craton thru the incorporation of other early cratons and exotic terranes.
I have been enjoying your presentations for the past several years. I studied geology on the East Coast -- UMass Amherst. Planning on returning for advanced degree -- maybe -- and your presentations both expose me to new geology in detail and refresh my old education -- LOL!!!
So Nick, basically in these a few streams, you are talking abou the Old North American Craton (>200millions)so that we later can have a better understanding of Exotic Terranes beyond strontium 706 line which had become in a picture between 200~50 million years ago..., right?😏
I really expected to hear a comment about how the Farallon plate can extend all the way to the eastern coast of America beneath the North American Crayton is there a video where you discuss it
Because of the 2:00 Friday format, I've chosen to not miss sessions, so I haven't been logging in on Sundays. Today started my learning - thank you so much! RE: 1972 Roadside Geology. I was earning a cool $1.10/hour in 72--73, so the book represents 4-5 hours of labor (because taxes, too)! It seems so inexpensive now, but back then that was a goodly amount to pay for a book! Happy Birthday, Patrick! And Nick, I used a credited image by Tom Foster in my stormwater classes, because my students now get a smidgeon of Central Washington Geology, too. I miss all of you - Sea from Woodland WA.
Nick you have me confused, which doesn't take much..Becraft and Weis speak of Cambrian-precambrain correlation, and an unconformity..the Deer Trail group is Precambrian, the Togo formation,the belt series
I think I never noticed rocks in photographs until watching the Nick from Home live streams. Now I seem to look for them and feel "at home" when I see them. Weird, I know.
I enjoy watching all of your videos they are so fun and educational. My family makes fun of me for my love of geology, saying its boring. I love coming here and being with like minded people!! Keep up the amazig videos!!
Grew up near Yellowstone (to the north/northwest), and we never really got as far east as the Beartooths. But some of those orange blobs seem mighty familiar. Madison Range, Gravelly Range, Tobacco Roots, the latter 2 seemingly some of your craton exposures. I've mentioned before my mom was a geology hobbyist (not just a rockhound; she liked to study the geology texts of the time which she snaggled out of the library at the then School of Mines in Butte). Watching your vids, BTW, is pure nostalgia for me. I used to know, and could identify, on a Montana map, all of the mountain rainges, but it's a slog now; I had to learn em for my Montana history class in 8th grade (1963-1964 so it's been a few years now). Speaking of Nostalgia, I also have a connection with ISU. She's gone now, but my mom's younger sister, Silvia, was secretary to the university president while you were a student there; lived with her hubby and kids in Chubbuck.
I love your presentations on NW geologic history. Regarding the Darcell well, why are the core box depths labeled ~8360 ft, whereas you have the total well depth only 7,000 ft deep? Core boxes are labeled with drilling depth from the surface.
Looked at Hildebrand's papers online, did not see that gorgeous map you showed in this session. Found several portions of it in different papers. Is this a file we can download and print? and if so, where is it?
The Road Side Geology books are and have been perfect for my mind and interest. But still would rather have a real geologist in the passenger seat. P.S. I love being able to watch these when I am free from working obligations.
sorry i didn't make the livestream... love all your video classes Nick. i think i want to go back to class A and take notes to get a deeper understanding
*ding* new idea hit me at 1:23:45 the chemistry of the land was/is different in Washington on this side of the line, which could have allowed the german chocolate cake to emerge there, with the weakness added with rotation
Portland, Oregon had a 33-1/3% chance of being named Boston in 1845. The City’s two founders, Francis Pettygrove from Portland, Maine and Asa Lovejoy from Boston, Massachusetts, both wanted to name the fledgling site-then known as The Clearing-after their respective home towns. The coin toss was decided with two out of three tosses.
I have joined the internet Zentnerds. remembering an an old anti nuclear bomb song fromthelate 1960's (to the tune of Mack the Knife) " When the shark bites/ With his teeth, dear/Scarlet billows/start to spread // Strontium 90/Leaves no colors/But it leaves you/Just as dead.
Craton, just some rock older than some other rock really. So North America has actually had exotic terranes being attached to whatever the original material was about 3.5 billion years ago. Its been going on for 3.5 billion years! We are way to focused on recent history. Last 200 million years. 🤔
