Why Oceanic Crust Is Thinner Than Continental Crust Upsc?

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Why is the oceanic crust thinner than the continental crust?

The oceanic crust is, on average, much thinner than continental crust and ranges in thickness from 6 to 10 kilometers. This is in part because oceanic crust is recycled through tectonic forces, and continental mostly is not.

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Why is continental crust thicker than oceanic crust?

Since the oceans are deep, a long column of water lies above the oceanic crust whereas the contintental crust is occupied by landmass for the same length of column. This explains that continental crust is thicker than the oceanic crust.

Is oceanic thinner than continental?

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.

Why continental crust is thicker but less dense?

Long story short – continental crust is thicker because is less dense, and it is less dense because it’s composed mostly of quartz and feldspars, both having density around 2.6 g/cm3, whereas oceanic crust is made up by slightly denser Ca feldspar called plagioclase as well as pyroxenes and olivine, both having density …

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Are oceanic plates thinner than continental crust?

Basalt is denser and heavier than the granite that makes up continental plates. Oceanic plates are much thinner than the continental plates. When an oceanic plate meets a continental plate at a convergent boundary the oceanic plate is forced under the continental plate and destroyed.

Why is oceanic plate heavier than continental plate?

The answer lies in the composition of the rocks. Continental crust is composed of granitic rocks which are made up of relatively lightweight minerals such as quartz and feldspar. By contrast, oceanic crust is composed of basaltic rocks, which are much denser and heavier.

How do oceanic crust and continental crust differ which is thicker which is denser?

Continental crust is thicker than oceanic crust, averaging 20-70 km thick, compared to 5-10 km for oceanic crust. Continental crust is less dense than oceanic crust (2.7 g/cm3 vs. 3 g/cm3), and it is much older.

Why is the crust different thickness?

The derived crustal thicknesses vary between 5 and 70km depending on the initial temperature distribution, the assumed amount of radioactive elements, and the mantle rheology.

Why continental is thicker?

The crust is thickened by the compressive forces related to subduction or continental collision. The buoyancy of the crust forces it upwards, the forces of the collisional stress balanced by gravity and erosion. This forms a keel or mountain root beneath the mountain range, which is where the thickest crust is found.

Where is the oceanic crust the thinnest?

Answer and Explanation: The Earth’s crust is thinnest under the ocean. The crust under the ocean is thinner because the crust under the water that is too old goes deeper into the mantle.