Stellar presentation, Dr. McKay! We're heading out to Bend for the second time in as many years and will be on the lookout for the insights you've described. Central Oregon is abundant in both ecological and geological beauty, and we cannot wait to take it all in. Would love to participate in something like this in the future!
I’m only as far as how water and oxygen change how the mantle behaves - with the salt and ice analogy: you have a great talent for explaining the basics! Thanks!
What an astonishingly great lecture. It was both wide and deep and answered questions that have been pestering me for years. I have wondered for ages about the implications of a continent running over a divergent boundary. This was the first time I've heard someone pretty much say straight out that this is connected to the basin and range extension. Also this was the first time I heard such a good explanation of the Nisqually (I'm sure to be spelling that incorrectly...dyslexia...I spell my own name incorrectly all the time) quake. So impressive. So much stuff explained so clearly and in such plain, understandable terms. The animations were excellent.
What is SVF in Washington? I know most of the rest, but I can’t figure out that one. I am really enjoying this. I follow Nick Zentner for WA geology but I’ve been looking for good programs on OR. Thanks for sharing.
Some say the composition of the Crooked River caldera rhyolites do not match up with the Yellowstone hot spot line of super volcanos rhyolites. Some say they do. Which is it?
What other hotspots migrate mid continent? Does it take thin accreted terrane to allow burn thru? I guess often hotspot is in rift like Ethiopia so not quite a migrating track... I guess there's the lil hotspot in BC. . . . Maybe super old ones now erased ...
Eifel hotspot in Germany, definitely mid-continent, but not migrating though. (And dormant; not dead). The way I (completely ignorant…) understand it, there’s some doubt about the hotspot-status: had it simply seized the opportunity of a breaking and stretching surface - or the other way around?
@@margreetanceaux3906 ... Besides physical rock reasons can volcanism occur in what should be quiet area due to chemistry of the rock allowing melting at normally inadequate temp/pressure. Can mineral type matter that much?... On the craton 150km thick hard to imagine vertical crack, vs California just 30km...
@@mostlyguesses8385 Born and raised (70 yrs) in Rotterdam, which is geologically speaking at the mouth of the Rhine, I only very recently learned that the Rhine goes through the ECRIS, the European Cenozoic Rift System. That’s a rift from (south) the mouth of the Rhône in the Mediterranean, to (north) the mouth of the Rhine in the North Sea. The Eifel hotspot is in or directly adjacent to that rift.
@@margreetanceaux3906 ... North America by Chicago almost rifted apart but stopped, and now the crust is thick there. Duluth Minnesota has cliffs from this volcanic rift leaking up magma... If you have thick square logs floating and 2 almost separate do they come back together and so there is no thin crust at the old rift? ...
@@mostlyguesses8385 I honestly have mo idea… There’s no ‘coming back together’. Basically the Rhine goes through a graben, and although it’s not highly active, it’s certainly not frozen in time. These rifts (as ignorant me understands it) are under pressure from the African continent moving northward, and the Mid-Atlantic Ridge, spreading between the North-American and European plates.
52:43 A better example of a thrust fault earthquake in Puget Sound from that northward squeezing motion would be the earthquake that took place 1,100 years ago on the Seattle Fault, which is the east-west fault that runs under Downtown Seattle and through Bremerton, etc. The NIsqually earthquake was a _slab_ earthquake that struck _within_ the subducting Juan de Fuca Plate, in and around the transition zone. The Nisqually quake was about 40-some miles deep where the JDF plate is curving downward toward the mantle and under the Cascades. It's not attributed to the northward squeezing of WA from the Oregon crustal block; but the Seattle quake is definitely caused by it.
The evidence of pending eruptions can extend over many months. Take for example Mt. St. Helens. In 1978 I observed steam venting near the summit of the mountain, sulfur being deposited along cracks in andesite bedrock miles from the mountain, soil profile temperatures much higher than typical in areas proximate to hydrothermally altered deposits miles from the mountain.
Can siletzia be called Continental Crust, it's seafloor rock made in huge gush that arrived submerged 1km and now 4km of Cascade sediment has covered it. East of Siletzia mid state is 20km of sediment to make dry land, not classic continental crust... imagine the Yakutat offshore in Alaska but little sediment on it, Oregon is muddier twin of that so get dry mud up top at Coos Bay..... Or not
Nice visuals. 🏔⛰ It's good to see more updated information. It's still rare to see anything about the Yellowstone hotspot going farther back than the past 3 major eruptions and/or anything pertaining to the clockwise rotation. Nice to see more. I like that you linked the Crooked River Caldera to the Yellowstone hotspot; however my understanding is that the current occurrence of clockwise rotation started ~16Ma and the previous occurrence was from ~85 Ma to 45 Ma. It's questionable that there was enough rotation inland to move / rotate the Crooked River caldera that far north, but the Straight Creek / Fraser fault (in Wa & BC) may have gone farther south and not be evident today due to the CRB covering it. I still think the Crooked River caldera may be associated with the Yellowstone hotspot though there is still debate. I'm surprised that one of the slides showed Siletzia but you didn't link Siletzia to the Yellowstone hotspot. 😕 I find it interesting that the bulk of the CRB was ~16 Ma, the San Andreas started ~16 Ma (though some have other dates), and that the clockwise rotation started ~16 Ma. 🏔🌋
It was a good overview, not much specifics to Central Oregon. Leaving out any mention of accreted Terranes that made all of OR/WA really misses the boat for explaining the variety of composition.
Toba is not the largest volcanic eruption on Earth by a long shot. There have been several that ejected over 5000 cubic kilometers. Look at La Garita as an example.
Thank you Dr. McKay, Paige and Deschutes Public Library. Very informative.
My family visited some lave tube caves in Bend, and went to the obsidian mountain. Pretty amazing sights!
Stellar presentation, Dr. McKay! We're heading out to Bend for the second time in as many years and will be on the lookout for the insights you've described. Central Oregon is abundant in both ecological and geological beauty, and we cannot wait to take it all in. Would love to participate in something like this in the future!
Great presentation, very informative, thanks for making it available.
That is the best geological presentation I've seen
Fantastic. I am glad I found this. Thank you.
Excellent presentation, thanks!
I’m only as far as how water and oxygen change how the mantle behaves - with the salt and ice analogy: you have a great talent for explaining the basics! Thanks!
very well done you got all the points, and very understandable. thank you
Wonderful program! Thank you!
Excellent presentation!! Thank you!🌋
An excellent presentation. Thank you for posting.
What an astonishingly great lecture. It was both wide and deep and answered questions that have been pestering me for years. I have wondered for ages about the implications of a continent running over a divergent boundary. This was the first time I've heard someone pretty much say straight out that this is connected to the basin and range extension.
Also this was the first time I heard such a good explanation of the Nisqually (I'm sure to be spelling that incorrectly...dyslexia...I spell my own name incorrectly all the time) quake.
So impressive. So much stuff explained so clearly and in such plain, understandable terms.
The animations were excellent.
Great thanks ❤❤❤
Thank you so much for doing this!
Outstanding, and those photos are stunning!
What is SVF in Washington? I know most of the rest, but I can’t figure out that one. I am really enjoying this. I follow Nick Zentner for WA geology but I’ve been looking for good programs on OR. Thanks for sharing.
Love this!!
Some say the composition of the Crooked River caldera rhyolites do not match up with the Yellowstone hot spot line of super volcanos rhyolites. Some say they do. Which is it?
Where is subduction occurring around Antarctica?
I see mid ocean ridge around Antarctica, but no subduction nor volcanism around Antarctic plate????
I'm watching 2 months later and I don't see any maps or graphics ???
Ok I fast forward a bit and see them now!!!
What other hotspots migrate mid continent? Does it take thin accreted terrane to allow burn thru? I guess often hotspot is in rift like Ethiopia so not quite a migrating track... I guess there's the lil hotspot in BC. . . . Maybe super old ones now erased ...
Eifel hotspot in Germany, definitely mid-continent, but not migrating though. (And dormant; not dead). The way I (completely ignorant…) understand it, there’s some doubt about the hotspot-status: had it simply seized the opportunity of a breaking and stretching surface - or the other way around?
@@margreetanceaux3906 ... Besides physical rock reasons can volcanism occur in what should be quiet area due to chemistry of the rock allowing melting at normally inadequate temp/pressure. Can mineral type matter that much?... On the craton 150km thick hard to imagine vertical crack, vs California just 30km...
@@mostlyguesses8385 Born and raised (70 yrs) in Rotterdam, which is geologically speaking at the mouth of the Rhine, I only very recently learned that the Rhine goes through the ECRIS, the European Cenozoic Rift System. That’s a rift from (south) the mouth of the Rhône in the Mediterranean, to (north) the mouth of the Rhine in the North Sea. The Eifel hotspot is in or directly adjacent to that rift.
@@margreetanceaux3906 ... North America by Chicago almost rifted apart but stopped, and now the crust is thick there. Duluth Minnesota has cliffs from this volcanic rift leaking up magma... If you have thick square logs floating and 2 almost separate do they come back together and so there is no thin crust at the old rift? ...
@@mostlyguesses8385 I honestly have mo idea… There’s no ‘coming back together’. Basically the Rhine goes through a graben, and although it’s not highly active, it’s certainly not frozen in time. These rifts (as ignorant me understands it) are under pressure from the African continent moving northward, and the Mid-Atlantic Ridge, spreading between the North-American and European plates.
52:43 A better example of a thrust fault earthquake in Puget Sound from that northward squeezing motion would be the earthquake that took place 1,100 years ago on the Seattle Fault, which is the east-west fault that runs under Downtown Seattle and through Bremerton, etc. The NIsqually earthquake was a _slab_ earthquake that struck _within_ the subducting Juan de Fuca Plate, in and around the transition zone. The Nisqually quake was about 40-some miles deep where the JDF plate is curving downward toward the mantle and under the Cascades. It's not attributed to the northward squeezing of WA from the Oregon crustal block; but the Seattle quake is definitely caused by it.
The evidence of pending eruptions can extend over many months. Take for example Mt. St. Helens. In 1978 I observed steam venting near the summit of the mountain, sulfur being deposited along cracks in andesite bedrock miles from the mountain, soil profile temperatures much higher than typical in areas proximate to hydrothermally altered deposits miles from the mountain.
Can siletzia be called Continental Crust, it's seafloor rock made in huge gush that arrived submerged 1km and now 4km of Cascade sediment has covered it. East of Siletzia mid state is 20km of sediment to make dry land, not classic continental crust... imagine the Yakutat offshore in Alaska but little sediment on it, Oregon is muddier twin of that so get dry mud up top at Coos Bay..... Or not
Nice visuals. 🏔⛰ It's good to see more updated information. It's still rare to see anything about the Yellowstone hotspot going farther back than the past 3 major eruptions and/or anything pertaining to the clockwise rotation. Nice to see more. I like that you linked the Crooked River Caldera to the Yellowstone hotspot; however my understanding is that the current occurrence of clockwise rotation started ~16Ma and the previous occurrence was from ~85 Ma to 45 Ma. It's questionable that there was enough rotation inland to move / rotate the Crooked River caldera that far north, but the Straight Creek / Fraser fault (in Wa & BC) may have gone farther south and not be evident today due to the CRB covering it. I still think the Crooked River caldera may be associated with the Yellowstone hotspot though there is still debate. I'm surprised that one of the slides showed Siletzia but you didn't link Siletzia to the Yellowstone hotspot. 😕 I find it interesting that the bulk of the CRB was ~16 Ma, the San Andreas started ~16 Ma (though some have other dates), and that the clockwise rotation started ~16 Ma.
🏔🌋
👍👍
It was a good overview, not much specifics to Central Oregon. Leaving out any mention of accreted Terranes that made all of OR/WA really misses the boat for explaining the variety of composition.
Toba is not the largest volcanic eruption on Earth by a long shot. There have been several that ejected over 5000 cubic kilometers. Look at La Garita as an example.
Audio is bad ...
30
Miller Sandra Johnson Brenda Wilson Cynthia
its mostly biology we have the net now come on man get with the times your getting left behind
we walk on giants turned to stone your missin at least half the big picture
Awesome video however, I disagree on your timelines. Yes, I am a Young Earth Creationist. ✌
whats hits utter nonsense? carbon dating,,, for the public schoold zombies