CWU's Nick Zentner from his home in Ellensburg, Washington on Thursday, April 2, 2020 during the global coronavirus pandemic. 0:00 Livestream Starts. 10:05 Lecture Begins.
So cool! I bet that explains the reason for the red granite, gold and other odd things you find here in Central Texas. Guessed it was more than an uplifted ocean sediment story. Always suspected a few old eroded volcanoes in our area with Enchanted Rock and some of the weird hills. Trying to find someone local online to check out with Texas info like you do for Washington! You got me curious! Thanks!
I knew the Cascades fed into the Sierras. There's a smidge of overlap in the north Sierras, in fact, with the Long Valley Caldera just east of the Sierra crest. But when I think of Granite Batholiths and erosion, I remember taking a good look at that magificent hunks of granite called Half Dome and El Capitan in Yosemite (granted, it was via a telescope at Mr. Hamilton Observatory above San Jose, but hey. I saw it.) Also saw lots of granite in King's Canyon NP south of Yosemite (and adjacent to Sequoia NP) when I actually visited.
Thank you to the person who posted the link to Cynthia's poster, for the life of me i couldn't it for sale. Nick, I'm trying to catch up, don't want to watch out of order. I have a ways to go. I will say I've been cheating though, it's a lot of fun with the live stuff! (I've seen everything you've done on RU-vid more than once anyway,) Glad I found you again!
This was interesting to watch, thank you Sir! I have got a question poppin up, while watching! The JDF plate is being created at the JDF ridge and is moving east and diving under the NA plate. The NA plate is moving west and will move towards the JDF ridge, which is stationary. So at 1 point the NA plate crosses the JDF ridge. The pacific plate is moving W or more NW? What will happen with that movement of the PA plate if the JDF ridge is gone...will the NA plate crawl over the PA plate?
I love how I can apply your lessons to my local Cascade geology down here in Southern Oregon. We have the enormous Ashland Pluton just to the west of the Cascades. What I find REALLY interesting is what's going on with your awesome interactive rotational map in my area.
Just wondering..Once the Juan de Fuca plate totally subducts, won't the North American plate be going over a hot spot which is currently creating the Juan de Fuca plate? Similar to the shifting Yellow Stone hot spot? Answered at 54:00
Keep up the good work, i really enjoy the mental banter and the creation, literally of newish rock! The question is: where would i be able to look up the geology of any particular place on the earth? like for instance central Mexico, north of Mexico City?
This lecture omits the southern segment of the Ancestral Cascades Arc -- which was active from 30-something to 3 million years ago. There's a break between the two segments, probably from a subducting slab tear between Shasta and Lassen. If anyone's interested: pubs.geoscienceworld.org/gsa/geosphere/article/10/1/1/132108/Petrologic-tectonic-and-metallogenic-evolution-of
the ghost volcanos separation space found between the 40m cascades and the 60m Idaho ghost volcanos is also a baja-bc story all that new exotic land in between
Hello from South Dakota, asking this several days late, but if the subduction ends in 10 million years - what happens when the spreading ridge goes under the continental crust? More flood basault s? Ken
Flood basalts are theorised to be caused by mantle hotspots, not spreading ridges. For a current example of hotspot plus mid ocean ridge see Iceland. However that doesn't mean that subducting spreading ridges doesn't do interesting things. See the Challis magmas for the sort of thing that he believes happens when a spreading ridge gets subducted.
Here is a link to where the book by P. Pringle can be downloaded. access.wa.gov/search-access-washington.html?q=Roadside+Geology+of+Mount+Rainier+National+Park+and+Vicinity
I scored a couple of them so I wouldn't have to flip it around, I can see both sides at once. I hope she enjoys the recognition. This will be her 15 minutes of fame thanks to Nick (and us!).
Does that mean that the continued westward movement of N.America over the stationary Juan de Fuca Ridge will create another “stationary” hotspot beneath the American continent
@@warhawkme6344 I got one from Amazon. I don't know if they have any more or how much they'd be. Other places have them at different prices. Shop around.
#NickZentner Random brain fart for you.. Rainier and St. Helens are next to each other and roughly adjacent to where the Columbia empties into the Pacific.. both having the most eruptive histories on the 4000yr eruption chart.. does the Columbia river possibly have anything to do with the higher activity in these two volcanoes? (millennia of less dense freshwater seepage into the volcanic system or possibly its sedimentary deposits on the ocean floor)
Having the active cones and the ghost volcanoes all evenly distributed along the Cascades surely can't be how it is, in Oregon at least -- where the (Ancestral) Western Cascades and the active High Cascades are very distinct. The distinction jumps out at you on a topo map. The situation seems more jumbled up in Washington, but it's a very tidy two ranges next to each other, in Oregon. Hmm, there actually aren't all that many exposed granitoid plutons in the Oregon Western Cascades (tends to be a little gold associated with most of them), now that I think of it. But I would assume frozen magma chambers in the Oregon High Cascades are all or mostly all underground still.
