I understand that the continental crust is the thicker crust so it sticks out, but if it's much less dense than the oceanic crust, why does the continental crust sink into the lithosphere much more than the oceanic one? Shouldn't a denser material sink in more? I'm having trouble grasping that haha
+sebastian sartorialissimo The continental lithosphere rides atop the underlying asthenosphere because the continental lithosphere is less dense than the underlying asthenosphere. Oceanic lithosphere is also less dense than underlying asthenosphere. It is for that reason they both sit atop the asthenosphere. IF you had a chunk of oceanic lithosphere and the same thickness chunk of continental lithosphere, "floating" side by side in asthenosphere, then yes, the continental lithosphere would ride higher than the oceanic lithosphere (sink down less) because oceanic lithosphere is denser than continental lithosphere. Denser objects will float lower in the water.Objects that float displace their equivalent mass in the material in which they float. Denser materials (same volume) are the more massive, so displace more (sink lower). So in all that, you're correct. However, continental lithosphere is much thicker than oceanic lithosphere, and so even though less dense it is much much more massive. Thus it must displace a much larger portion of asthenosphere and sinks lower (as well as rising higher). I hope this helps. :)
Katryn Wiese It does help, Katryn! Thank you so much for taking the time to answer. I actually Googled you just to know what sort of professional background you have and I must say I'm honoured to have had an oceanography and geology Professor answer my question! Thank you very much! Greetings from Mexico City. =)
It's a song written by Proceed With Caution, an amateur jazz group in Seattle that has no online presence. Name: Track 4. (Not very catchy name, but catchy tune, eh?)
