Oceanic crust differs from continental crust in several ways: it is
thinner, denser, younger, and of different chemical composition
. Like continental crust, however, oceanic crust is destroyed in subduction zones.
Which 2 terms apply to oceanic crust rather than continental crust?
Oceanic crust differs from continental crust in several ways: it is
thinner, denser, younger, and of different chemical composition
. Like continental crust, however, oceanic crust is destroyed in subduction zones.
What is the difference between the continental crust and the oceanic crust?
The crust is the outer layer of the Earth. It is the solid rock layer upon which we live. … Continental crust is typically 30-50 km thick, whilst
oceanic crust is only 5-10 km thick
. Oceanic crust is denser, can be subducted and is constantly being destroyed and replaced at plate boundaries.
What are two differences between oceanic crust and continental crust quizlet?
The oceanic crust is thinner and denser
, and is similar in composition to basalt (Si, O, Ca, Mg, and Fe). The continental crust is thicker and less dense, and is similar to granite in composition (Si, O, Al, K, and Na). The mantle is made of magnesium, iron and silicon. The core is almost exclusively iron and nickel.
What are two of the three main differences between continental crust and oceanic crust?
Continental crust is low in density whereas oceanic crust has a higher density
. Continental crust is thicker, on the contrary, the oceanic crust is thinner. Continental crust floats on magma freely but oceanic crust floats on magma scarcely. Continental crust cannot recycle whereas oceanic crust can recycle it.
Is oceanic crust older than continental?
Continental crust is almost always much older than oceanic crust
. Because continental crust is rarely destroyed and recycled in the process of subduction, some sections of continental crust are nearly as old as the Earth itself.
Which crust is thicker continental or oceanic?
Continental crust is typically 40 km (25 miles) thick, while
oceanic crust is
much thinner, averaging about 6 km (4 miles) in thickness.
Why is continental crust thicker than oceanic?
Layers that are less dense, such as the crust, float on layers that are denser, such as the mantle. Both oceanic crust and continental crust are less dense than the mantle, but
oceanic crust is denser than continental crust
. This is partly why the continents are at a higher elevation than the ocean floor.
What is an example of oceanic crust?
An example of this is
the Gakkel Ridge under the Arctic Ocean
. Thicker than average crust is found above plumes as the mantle is hotter and hence it crosses the solidus and melts at a greater depth, creating more melt and a thicker crust. An example of this is Iceland which has crust of thickness ~20 km.
What are the properties of continental crust?
The continental crust is the layer of
granitic, sedimentary and metamorphic rocks
which form the continents and the areas of shallow seabed close to their shores, known as continental shelves. It is less dense than the material of the Earth’s mantle and thus “floats” on top of it.
What is the thickness and composition of oceanic crust?
On average, oceanic crust is
6–7 km thick and basaltic
in composition as compared to the continental crust which averages 35–40 km thick and has a roughly andesitic composition.
What is an example of continental crust?
The continental crust is the
layer of granitic, sedimentary, and metamorphic rocks
, which form the continents and the areas of shallow seabed close to their shores (continental shelves).
How will you differentiate the two types of crust?
Earth’s Crust
There are two different types of crust:
thin oceanic crust that underlies the ocean basins, and thicker continental crust that underlies the continents
. … The thin oceanic crust is composed of primarily of basalt, and the thicker continental crust is composed primarily of granite.
Why is there no old oceanic crust?
Most oceanic crust is less than 200 million years old, because
it is typically recycled back into the Earth’s mantle at subduction zones
(where two tectonic plates collide).
Where is the oldest oceanic crust found?
The oldest patch of undisturbed oceanic crust on Earth may lie
deep beneath the eastern Mediterranean Sea
– and at about 340 million years old, it beats the previous record by more than 100 million years.
What is the oldest crust on Earth?
Earth’s oldest known piece of continental crust dates to the era of the moon’s formation.
Australia
holds the oldest continental crust on Earth, researchers have confirmed, hills some 4.4 billion years old.
