How do you tell the age of the volcanic rock? I mean it's magma for probably millions of years, it cools to become a rock, but is essentially made up of the same carbon / elements just colder/solid now. Once lava turns to rock what is the change that makes you able to tell its age ?
While erosion would make the mountains smaller the main reason is the old islands are actually sinking back into the ocean. (Keep in mind they how massive they are, they will always be fighting gravity to keep their lofty heights)
This is a bit esoteric but the hot spot that causes the Hawaiian islands may have been caused by an antipodal meteor strike (that is a strike on the opposite side of the Earth)
Nice try, but I would expect you have seen the materials you're talking about before the talk and a few disturbing sequences as "_really hot_ material can _kinda_ rise up".
Still I think your/his intonation was not boring.
Hey, could I somehow get your contacts, please? I'm a junior geologist and sometimes I find it dificult understanding things... But I really love the science, so I'd like to complete my course and graduate... So.. if that wouldn't be that difficult, could you sometimes simply explain those to me. You talk human language, and my lecturer does not... -.-
0:52 I SAW THE VOLCANOES ERUPT WHEN I WAS THERE!!!!!!!! we r going AGAIN this christmas...it'l be my 11th time...blech i hate the long airplane rides....
Sal, Hawaii is pronounced ha-wa-ee, not ha-why-ee. Or, if you want to get really close, the natives pronounce it ha-va-ee. Just thought this would be a cool fact...
AUTubeN22: One should not expect to find granite on Hawaii (unless it arrived on a boat or plane). Deep mantle plumes bring iron rich basaltic magma to the reservoir beneath the the Big Islands of Hawaii. This magma is low in silica and just will not produce much potassium or sodium feldspar, and quartz -- the primary minerals found in granite. Continents, particularly very old interior cratons of continents, are granitic. Google Fractional Crystalization+continents, and Bowen's Reaction series
@AUTubeN22 There were different types of lava. The fast flowing lava was called pahoehoe and was more smooth. When pahoehoe hit a bump (like a rock) it created crazy shapes.
I have a theory... The continents are actually the remnant of when Thea hit the Earth. Is it all that crazy? Why else would there be one huge mass then break apart into the continents we know today?
@adkinsjr The same NephilimFree in the earphones who keeps getting his bullshit debunked and constantly pussing out of debates with people who actually knows what they're talking about? LMAO
6:08 Mauna Kea is the name of the mountain you are mentioning.
Loihi is the name of the next underwater mountain to break the surface of the pacific ocean long after most of us are dead. So indeed the hot spot has indeed shifted and the volcanic activity in Kilauea and Manua Loa has been minimal.
In the past Ancient Hawaiians believed that The big island was the oldest island and that the goddess Pele moved from Tahiti to Hawaii.
How do you tell the age of the volcanic rock? I mean it's magma for probably millions of years, it cools to become a rock, but is essentially made up of the same carbon / elements just colder/solid now. Once lava turns to rock what is the change that makes you able to tell its age ?
MrAartJansen 3 weeks ago
sal what do you do by proffesion you teach calculus and geology?
Kortugal 3 weeks ago
While erosion would make the mountains smaller the main reason is the old islands are actually sinking back into the ocean. (Keep in mind they how massive they are, they will always be fighting gravity to keep their lofty heights)
This is a bit esoteric but the hot spot that causes the Hawaiian islands may have been caused by an antipodal meteor strike (that is a strike on the opposite side of the Earth)
Pyrolonn 1 month ago
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Nice try, but I would expect you have seen the materials you're talking about before the talk and a few disturbing sequences as "_really hot_ material can _kinda_ rise up".
Still I think your/his intonation was not boring.
UserHuge 1 month ago
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UserHuge 1 month ago
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There's actually a new island called Lōʻihi that's forming off the coast of the Big Island. :)
gkng 1 month ago
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gkng 1 month ago
Very interesting. So does this pattern apply to the formation of island chains in general? To the Aleutian Islands e.g.? Hot Spot there, too?
btq28 1 month ago
@khanacademy:
GREAT VID, MATE!
Hey, could I somehow get your contacts, please? I'm a junior geologist and sometimes I find it dificult understanding things... But I really love the science, so I'd like to complete my course and graduate... So.. if that wouldn't be that difficult, could you sometimes simply explain those to me. You talk human language, and my lecturer does not... -.-
slashwalkerable 2 months ago
I was going to masterbate to this then I found myself learning!
StargateMunky 2 months ago
@StargateMunky why and the hell would you masterbate to a mans voice talking about science? freak
alyzsha123 3 weeks ago
moore geo!
32simas 3 months ago
Subduction is still speculative science, even still I appreciate the shared observations.
phonic0photon 3 months ago
Very helpful when you can't understand what your geography book is trying to explain ..... :0)
bigislechicka 3 months ago
0:52 I SAW THE VOLCANOES ERUPT WHEN I WAS THERE!!!!!!!! we r going AGAIN this christmas...it'l be my 11th time...blech i hate the long airplane rides....
jadynhope 4 months ago
Sal, Hawaii is pronounced ha-wa-ee, not ha-why-ee. Or, if you want to get really close, the natives pronounce it ha-va-ee. Just thought this would be a cool fact...
jadynhope 4 months ago
thanks man :D
Carrotlocks 10 months ago
AUTubeN22: One should not expect to find granite on Hawaii (unless it arrived on a boat or plane). Deep mantle plumes bring iron rich basaltic magma to the reservoir beneath the the Big Islands of Hawaii. This magma is low in silica and just will not produce much potassium or sodium feldspar, and quartz -- the primary minerals found in granite. Continents, particularly very old interior cratons of continents, are granitic. Google Fractional Crystalization+continents, and Bowen's Reaction series
EmeJonBuang 10 months ago
Is there a geology section in Khan Academy yet or is it still in the astronomy section? 'cause it doesn't belong there. But thanks for the vids!
imtosexyformyself 10 months ago
why is there different types of volcanic rock? granite takes much longer to erode!
AUTubeN22 1 year ago
@AUTubeN22 There were different types of lava. The fast flowing lava was called pahoehoe and was more smooth. When pahoehoe hit a bump (like a rock) it created crazy shapes.
jadynhope 4 months ago
The hot spot the creates the islands also pushes the earths crust up so as the Islands move away from the hot spot they drop into the ocean.
deadman12078 1 year ago
I have a theory... The continents are actually the remnant of when Thea hit the Earth. Is it all that crazy? Why else would there be one huge mass then break apart into the continents we know today?
deadman12078 1 year ago
will loihi be part of america when it comes up?
Haradin32 1 year ago
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These island formed very quickly. NephilimFree has proof of this on his youtube channel. Khanacademy is propagated evolutionists lies.
adkinsjr 1 year ago
@adkinsjr The same NephilimFree in the earphones who keeps getting his bullshit debunked and constantly pussing out of debates with people who actually knows what they're talking about? LMAO
Tonio31 1 year ago
@adkinsjr NephilimFree is a liar.
m3th0dm4n 1 year ago
@adkinsjr Lol.
Poleschs 1 year ago
Theory or hypothesis?
IslandAtheist 1 year ago
@IslandAtheist Theory I believe.
Poleschs 1 year ago
Is this part of the cosmology & astronomy playlist or a new geography playlist?
hedonism13 1 year ago
@hedonism13 its geology not geography i think
ILockItDown 1 year ago
6:08 Mauna Kea is the name of the mountain you are mentioning.
Loihi is the name of the next underwater mountain to break the surface of the pacific ocean long after most of us are dead. So indeed the hot spot has indeed shifted and the volcanic activity in Kilauea and Manua Loa has been minimal.
In the past Ancient Hawaiians believed that The big island was the oldest island and that the goddess Pele moved from Tahiti to Hawaii.
Hawaiian Pride!!!
manoftheleaf 1 year ago
Yay. Thanks
alexandrenr 1 year ago