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 3 differences between oceanic and continental 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.
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 the similarities and differences between the oceanic crust and continental crust?
The
continental crust is made mostly of rocks with a composition similar to granite
(a light-colored rock you would expect to find in the Sierra Nevada), whereas the oceanic crust is made mostly of rocks with a composition of basalt (a dark- colored rock, like the rocks that make up the Hawaiian volcanoes).
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).
What are the characteristics of the continental crust?
Continental crust is
broadly granitic in composition
and, with a density of about 2.7 grams per cubic cm, is somewhat lighter than oceanic crust, which is basaltic (i.e., richer in iron and magnesium than granite) in composition and has a density of about 2.9 to 3 grams per cubic cm.
What are the 2 kinds of crust differentiate them?
Earth’s crust is divided into two types:
oceanic crust and continental crust
. The transition zone between these two types of crust is sometimes called the Conrad discontinuity. Silicates (mostly compounds made of silicon and oxygen) are the most abundant rocks and minerals in both oceanic and continental crust.
What happens when continental and oceanic crust collide?
When they collide,
the Oceanic crust sinks below the continent
. … Some of this crust joins the mantle, but lighter materials will rise up through the continent to emerge on the surface as volcanoes, melting some continental crust with it on the way up.
What do oceanic and continental crust have in common?
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. … As a result, the rock that forms from that melt is less dense than the original rock.
Which type of crust is usually the oldest?
The oldest
oceanic crust
is about 260 million years old. This sounds old but is actually very young compared to the oldest continental rocks, which are 4 billion years old.
What is the average age of continental crust?
On the basis of Nd model age provinces in North America and Australia an average age of continental crust is
about 2.0 Ga
.
Why is continental crust important?
The crust is a thin but important zone where
dry
, hot rock from the deep Earth reacts with the water and oxygen of the surface, making new kinds of minerals and rocks. It’s also where plate-tectonic activity mixes and scrambles these new rocks and injects them with chemically active fluids.
What is the thickness of continental crust?
Global observations show that the crustal thickness varies through the tectonic regions. While the continental crust is
30–70 km thick
, the oceanic crustal thickness is 6–12 km. The oceanic crust is also denser (2.8–3.0 g/cm
3
) than the continental crust (2.6–2.7 g/cm
3
).
What are the main features of crust?
The crust is made of
solid rocks and minerals
. Beneath the crust is the mantle, which is also mostly solid rocks and minerals, but punctuated by malleable areas of semi-solid magma. At the center of the Earth is a hot, dense metal core.
What are 5 facts about the crust?
- The crust is deepest in mountainous areas. …
- The continental and oceanic crusts are bonded to the mantle, which we spoke about earlier, and this forms a layer called the lithosphere. …
- Beneath the lithosphere, there is a hotter part of the mantle that is always moving.
What are the 3 kinds of crust?
- Primary crust / primordial crust.
- Secondary crust.
- Tertiary crust.
