What are the characteristics of oceanic and continental crust?
It is the solid rock layer upon which we live. It is either continental or oceanic. 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 2 characteristics of continental crust?
The average composition is granite, which is much less dense than the mafic rocks of the oceanic crust (Figure 3). Because it is thick and has relatively low density, continental crust rises higher on the mantle than oceanic crust, which sinks into the mantle to form basins.
What are the characteristics of Continental?
Continental is a descriptive term that is general rather than specific. It includes temperature extremes, large diurnal and seasonal ranges of temperature, small annual precipitation totals, and low relative humidities. Perhaps the most diagnostic condition of a continental climate is a large range of temperature.
What is the characteristic of oceanic 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. The lavas are generally of two types: pillow lavas and sheet flows.
What are the main features of crust?
In geology, a crust is the outermost layer of a planet. The crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks. The crust is underlain by the mantle. The upper part of the mantle is composed mostly of peridotite, a rock denser than rocks common in the overlying crust.
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, known as continental shelves. About 40% of the Earth’s surface is now underlain by continental crust.
What is the meaning of continental crust?
The continental crust is typically defined as that portion of the outer rocky layer of the Earth that extends vertically from the surface (subaerial or submarine) to the Mohorovicic discontinuity (or Moho) and laterally to the slope break on continental shelves (Cogley 1984).
Why continental crust is thicker?
At convergent plate boundaries, where tectonic plates crash into each other, continental crust is thrust up in the process of orogeny, or mountain-building. For this reason, the thickest parts of continental crust are at the world’s tallest mountain ranges.
What are three differences between continental 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.
What are the similarities and differences between oceanic and continental crust?
The oceanic crust is mainly made out of dark basalt rocks that are rich in minerals and substances like silicon and magnesium. By contrast, the continental crust is made up of light-colored granite rocks full of substances like oxygen and silicon.
What are the 2 kinds of crust differentiate them?
There are two different types of crust: thin oceanic crust that underlies the ocean basins, and thicker continental crust that underlies the continents. These two different types of crust are made up of different types of rock.
What are the similarities between oceanic and continental crust?
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Oceanic and Continental crusts are alike because they both shift and move and grow. They differ by there rock types. Oceanic crust is made up of dense basalt while continental crust is made up of less dense granite.
How is oceanic crust different from continental crust quizlet?
How do oceanic and continental crust differ? Continental crust consists mainly of less dense rocks such as granite. Oceanic crust consists of mainly denser rocks such as basalt.
Is continental crust thicker than oceanic?
The continental crust is also less dense than oceanic crust, although it is considerably thicker. As a consequence of the density difference, when active margins of continental crust meet oceanic crust in subduction zones, the oceanic crust is typically subducted back into the mantle.
How do the properties of oceanic crust rock and continental crust rock differ?
Both oceanic crust and continental crust are less dense than the mantle, but oceanic crust is denser than continental crust. Because continental crust is less dense than oceanic crust it floats higher on the mantle, just like a piece of Styrofoam floats higher on water than a piece of wood does.
Why does continental crust stand higher on the mantle than oceanic crust?
Areas of continental crust stand higher than areas of oceanic crust, because continental crust is THICKER and LESS DENSE than oceanic crust. The deepest parts of the ocean are near the continents, and out in the middle of the ocean, the water is relatively shallow.
Why is continental crust higher than oceanic crust quizlet?
Why is continental crust higher than oceanic crust? Oceanic crust is much denser than continental crust, so it tends to sink to the upper mantle and subduct, in a kind of constant recycling system. Continental crust is too light to do this.
What is the chemical composition of the continental crust?
A new estimate of the bulk continental crust is reported consisting of 57 percent lower crust (60% felsic and 40% mafic granulites) and 43 percent upper crust. The proportions of crustal units are based on petrological observations (Bohlen &Mezger, 1989).