EARTH SCIENCE
TECTONICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Younger and less dense than continental crust
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Thinner, younger and more dense than continental crust
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Older, thicker and less dense that continental crust
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Bigger and younger than continental crust
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Detailed explanation-1: -Continental crust is typically 40 km (25 miles) thick, while oceanic crust is much thinner, averaging about 6 km (4 miles) in thickness. The effect of the different densities of lithospheric rock can be seen in the different average elevations of continental and oceanic crust.
Detailed explanation-2: -Earth’s crust is generally divided into older, thicker continental crust and younger, denser oceanic crust.
Detailed explanation-3: -The Earth is covered by two kinds of crust-continental and oceanic. The thinner oceanic crust is normally a little more than four miles thick, while the thicker continental crust is often as much as 25 miles thick. Continental crust is also much less dense than its oceanic counterpart.
Detailed explanation-4: -As stated, oceanic plates are denser than continental ones. This is because they are made of denser rocks. Oceanic plates are typically composed of basalt. Basalts are mafic igneous rocks, which means they have a silica (quartz) content of less than 20% and are created by the cooling of lava.
Detailed explanation-5: -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.