Why is more oceanic crust more dense than continental crust?
Oceanic crust averages 3 grams per cubic centimeter, Continental crust averages 2.7 grams per cubic centimeter. The difference lies in the rock which composes each type of crust. Oceanic crust is mainly basalt and continental crust is more like granite. Basalt is more dense (heavier) than granite.
How do the densities of oceanic crust and continental crust influence what happens when an oceanic plate coverages with a continental plate?
Oceanic crust is more dense than continental crust. All that water weight compresses the heck out of the material in the plate and also the oceanic crust contains larger percentages of denser elements such as magnesium and iron than the continental crust which also contributes to it's higher density. This sets the conditions for what happens. The more dense oceanic crust will "dive under" continental crust because it is more dense, and all because of…
Continental crust is thicker and less dense while oceanic crust is thinner and more dense, so essentially continental crust takes a higher position than oceanic crust. When oceanic and continental plates collide, oceanic plates slide underneath continental plates(if this makes what I said any clearer).
Because magma rises through hot spots( holes in the ground on the ocean floor) and cools forming new crust which repeats over hundreds of years making the oceanic crust more dense than continental crust. Since the oceanic crust is more dense, it sinks faster causing it to slide under the continental crust
Oceanic crust is more dense than continental crust. As a result, over time, continental crust is harder to "recycle". Rocks are recycled when they are subducted and remelted. Since continental crust is harder to subduct (it wants to keep floating), it is not recycled as much as oceanic crust, which is dense and will sink and remelt.
Both are composed of solid rock. Both plate types are part of the lithosphere. Both plates float on the asthenosphere. Oceanic crust is more dense than continental crust. Oceanic crust is largely basaltic rock; continental crust is mostly granitic. Only oceanic crust subducts. Continental crust is thicker than oceanic crust. Oceanic crust, for the most part, is much younger than continental crust.
What happens when more dense oceanic crust of Nazca Plate converges with the less dense continental crust of the south America Plate?
The oceanic crust slides under the continental crust due to the differences in their densities. The continental crust is more felsic (contains more silica) which makes it lighter than the oceanic crust which is more mafic (containes more fe and mg). Because the process of subduction is very slow, gravitational forces have a stronger effect on the more dense oceanic crust, causing this crust to be pulled under the continental crust and down into the…
Convergent plate margins are characterized as collision zones between plates and may involve continental to continental crust, continental to oceanic crust, or oceanic to oceanic crust. Those that involve oceanic crust result in subduction of the more dense plate into the Earth's mantle. Continental to continental plate collisions result in uplift of the surface features and mountain building and the margin may eventually become welded together.