Hi Wyatt: I think of it as a little like what would happen if you floated a thin sheet of plywood in a lake, then put a rock right in the middle of the sheet. The sheet would bow downward, displacing the water underneath. What's really happening is the lithospheric plate is bending downward from the weight of the massive volcanoes, and the asthenosphere, the part of the mantle beneath the lithosphere/plate, flows out of the way. Since sea level doesn't change much, in effect, the volcano 'sinks' below the surface of the ocean. Best, Jerry
Jerry, this was posted in 2015, and I don't know if YT notifies its authors when new comments are made. I'll try anyway: If "hot spots" are from the lithosphere and crust, is there anywhere on earth that lava from the core makes it to the surface? And what started these "hot spots", in the first place? Also, it appears that in spite of plate movement, the Hawaiian Chain, Aleutian Trench and Emperor Sea Mounds had the same or similar origin site. Is that the case? Anyway, I loved the video. Thanks for all your work.
First, we think that for some of the hotspots, there's a conduit of hot material, apparently originating near the core/mantle boundary, that flows up through the mantle, arriving at the underside of the lithosphere. It may pond there, as shown in my animation, and then some material travels up through the lithosphere, and some of this arrives at the surface in the form of lava flows and volcanic eruptions. But it is extremely hard for seismologists to detect and "see" this process. And no, it's not the material from the core-mantle boundary area that flows out onto the surface as a lava flow. It's the wrong composition, so the process is more complicated than that. You're correct that the Emperor Seamounts and the Hawaiian chain were produced by what we call the "Hawaiian Hot Spot"; the bend in the chain must have been produced by a change in direction of the Pacific Plate right around the time Midway Island formed. But the Aleutian Islands are completely different. They're stratovolcanoes, of an andesite (not basalt) composition, produced by subduction of the Pacific Plate. You can easily tell the difference: the Aleutian islands form an arc (curving) shape, whereas the Hawaiian Islands/Emperor Seamounts are straight (linear).
Ask yourself what happens eventually to the rock that comes to the surface as lava. Learn about the Mid-Atlantic Ridge and the Mariana Trench. The Earth is not getting larger because of volcanoes.
I definitely want to see more of these videos.
.
Great videos! Please make more - you are a great writer and narrator!
i love how you put a finishing touch on it with the music! Really fitting :)
Thanks for sharing!
Geology 101: Excellent explanation!
Nice video!!! Well done!
I'm on Oahu
Why does the cooled Volcanic rock sink downwards in the formation of an atoll? Something to do with a deflating magma chamber perhaps?
Hi Wyatt: I think of it as a little like what would happen if you floated a thin sheet of plywood in a lake, then put a rock right in the middle of the sheet. The sheet would bow downward, displacing the water underneath. What's really happening is the lithospheric plate is bending downward from the weight of the massive volcanoes, and the asthenosphere, the part of the mantle beneath the lithosphere/plate, flows out of the way. Since sea level doesn't change much, in effect, the volcano 'sinks' below the surface of the ocean. Best, Jerry
more videos .good to share
Good share. ..
Ich bin überzeugt, danke geolehrerin
This is great! I didn't know about the modern conception of melting anomalies. I would love to see more.
Love your videos. Please make more on volcanos
Thanks a lot. I'd love to make new ones. Need a good benefactor though.
you've got a talent for this.please do more
Absolutely fascinating!
I watched this for science class, thank
Great video! One thing though Hualalai is pronounced something like who-ah-la-lie
Hey, thanks. Yes, unfortunately I figured that out well after I recorded this one. I try to be very careful but sometimes they slip through.
Jerry Magloughlin no worries, I just thought I’d help with the Hawaiian pronunciation because it can be tricky sometimes. Aloha 🤙🏽🌺
Jerry, this was posted in 2015, and I don't know if YT notifies its authors when new comments are made. I'll try anyway: If "hot spots" are from the lithosphere and crust, is there anywhere on earth that lava from the core makes it to the surface? And what started these "hot spots", in the first place? Also, it appears that in spite of plate movement, the Hawaiian Chain, Aleutian Trench and Emperor Sea Mounds had the same or similar origin site. Is that the case? Anyway, I loved the video. Thanks for all your work.
First, we think that for some of the hotspots, there's a conduit of hot material, apparently originating near the core/mantle boundary, that flows up through the mantle, arriving at the underside of the lithosphere. It may pond there, as shown in my animation, and then some material travels up through the lithosphere, and some of this arrives at the surface in the form of lava flows and volcanic eruptions. But it is extremely hard for seismologists to detect and "see" this process. And no, it's not the material from the core-mantle boundary area that flows out onto the surface as a lava flow. It's the wrong composition, so the process is more complicated than that.
You're correct that the Emperor Seamounts and the Hawaiian chain were produced by what we call the "Hawaiian Hot Spot"; the bend in the chain must have been produced by a change in direction of the Pacific Plate right around the time Midway Island formed. But the Aleutian Islands are completely different. They're stratovolcanoes, of an andesite (not basalt) composition, produced by subduction of the Pacific Plate. You can easily tell the difference: the Aleutian islands form an arc (curving) shape, whereas the Hawaiian Islands/Emperor Seamounts are straight (linear).
I like commenting
di menit 3:47 dibelakang kok ada benda berasap jalan. perhatiin dah
moving 10cm per year you say. I think the earth is getting larger.
Ask yourself what happens eventually to the rock that comes to the surface as lava. Learn about the Mid-Atlantic Ridge and the Mariana Trench.
The Earth is not getting larger because of volcanoes.
And 100 ton dinosaurs walked around without breaking bones or suffocating under their own weight. The earth is growing larger.
Oh, you're one of those *special* types of idiots. Okay, then.
you can't prove it's not getting larger