<p><strong>Continental Crust</strong> forms because of continual volcanic magma flow and pressure, erosion takes over a period of hundreds to millions of years to completely weather some object. Along with that, tectonic plates can smash into each other to form a continental crust and do land-building (The Himalayas is an exemple)</p>
<blockquote>
<p>As with oceanic crust, continental crust is created by plate tectonics. 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. Like icebergs, the tall peaks of the Himalayas and the Andes are only part of the region’s continental crust—the crust extends unevenly below the Earth as well as soaring into the atmosphere.</p>
</blockquote>
<blockquote>
<p>“Crust” describes  the outermost shell of a terrestrial planet. Our planet’s thin, 40-kilometer (25-mile) deep crust—just 1% of Earth’s mass—contains all known life in the universe.</p>
</blockquote>
<blockquote>
<p>Earth has three layers: the crust, the mantle, and the core. 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.</p>
</blockquote>
<blockquote>
<p>Earth’s layers constantly interact with each other, and the crust and upper portion of the mantle are part of a single geologic unit called the lithosphere. The lithosphere’s depth varies, and the Mohorovicic discontinuity (the Moho)—the boundary between the mantle and crust—does not exist at a uniform depth. Isostasy describes the physical, chemical, and mechanical differences between the mantle and crust that allow the crust to “float” on the more malleable mantle. Not all regions of Earth are balanced in isostatic equilibrium. Isostatic equilibrium depends on the density and thickness of the crust, and the dynamic forces at work in the mantle.</p>
</blockquote>
<blockquote>
<p>Just as the depth of the crust varies, so does its temperature. The upper crust withstands the ambient temperature of the atmosphere or ocean—hot in arid deserts and freezing in ocean trenches. Near the Moho, the temperature of the crust ranges from 200° Celsius (392° Fahrenheit) to 400° Celsius (752° Fahrenheit).</p>
</blockquote>
<blockquote>
<p>Crafting the Crust</p>
</blockquote>
<blockquote>
<p>Billions of years ago, the planetary blob that would become the Earth started out as a hot, viscous ball of rock. The heaviest material, mostly iron and nickel, sank to the center of the new planet and became its core. The molten material that surrounded the core was the early mantle.</p>
</blockquote>
<blockquote>
<p>Over millions of years, the mantle cooled. Water trapped inside minerals erupted with lava, a process called “outgassing.” As more water was outgassed, the mantle solidified. Materials that initially stayed in their liquid phase during this process, called “incompatible elements,” ultimately became Earth’s brittle crust.</p>
</blockquote>

CC BY-SA 4.0
2021-03-25T15:43:53.153Z
From where do the quotes come? Please incorporate the reference links in the answer.
Fred
CC BY-SA 4.0
2021-03-25T12:48:06.770Z
2021-03-25T12:48:06.770Z
Tardy
<p>New oceanic crust is formed at mid-ocean ridges, then destroyed during subduction. Continental crust can be destroyed with erosion, or when the crust gets too thick (under mountains) and starts to melt at the base, but how does it form? Or is the continental crust slowly disappearing?</p>

CC BY-SA 4.0
2021-03-08T23:08:15.640Z
[How Does Earth's Continental Crust Form? A New Bottom-Up Theory](https://blogs.ei.columbia.edu/2016/02/22/how-does-continental-crust-form-scientists-have-a-new-bottom-up-theory/)
Keith McClary
CC BY-SA 4.0
2021-03-09T08:44:03.710Z
See also: https://earthscience.stackexchange.com/q/19261/18081
Jean-Marie Prival
CC BY-SA 4.0
2021-03-09T09:05:53.413Z
*points at Iceland* *points at the Mid-African ridge* Your question was?
Erik
CC BY-SA 4.0
2021-03-09T16:12:08.280Z
@Erik I thought that Iceland was mostly basaltic because it is sitting on a mid-ocean ridge, so it's not quite continental crust that is being formed there. As for the Mid-African ridge, I believe the continental crust is getting locally thinner as it is spreading out, so the volume of continental crust is staying the same.
usernumber
CC BY-SA 4.0
2021-03-11T12:25:51.910Z
@Erik: Sounds like you would want to formulate a coherent answer?
AtmosphericPrisonEscape
<continental-crust>
How does new continental crust form?
usernumber
# How does new continental crust form?

(Asked by: username_0 on 2021-03-08)

New oceanic crust is formed at mid-ocean ridges, then destroyed during subduction. Continental crust can be destroyed with erosion, or when the crust gets too thick (under mountains) and starts to melt at the base, but how does it form? Or is the continental crust slowly disappearing?

**Tags:** continental-crust

> **Comments:**
> **username_1**: [How Does Earth's Continental Crust Form? A New Bottom-Up Theory](https://blogs.ei.columbia.edu/2016/02/22/how-does-continental-crust-form-scientists-have-a-new-bottom-up-theory/)  
> **username_2**: See also: https://earthscience.stackexchange.com/q/19261/18081  
> **username_3**: *points at Iceland* *points at the Mid-African ridge* Your question was?  
> **username_0**: @username_3 I thought that Iceland was mostly basaltic because it is sitting on a mid-ocean ridge, so it's not quite continental crust that is being formed there. As for the Mid-African ridge, I believe the continental crust is getting locally thinner as it is spreading out, so the volume of continental crust is staying the same.  
> **username_4**: @username_3: Sounds like you would want to formulate a coherent answer?  

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## 1 answers

### Answer by username_5 on 2021-03-25. Score: 0

**Continental Crust** forms because of continual volcanic magma flow and pressure, erosion takes over a period of hundreds to millions of years to completely weather some object. Along with that, tectonic plates can smash into each other to form a continental crust and do land-building (The Himalayas is an exemple)

> As with oceanic crust, continental crust is created by plate tectonics. 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. Like icebergs, the tall peaks of the Himalayas and the Andes are only part of the region’s continental crust—the crust extends unevenly below the Earth as well as soaring into the atmosphere.

> “Crust” describes the outermost shell of a terrestrial planet. Our planet’s thin, 40-kilometer (25-mile) deep crust—just 1% of Earth’s mass—contains all known life in the universe.

> Earth has three layers: the crust, the mantle, and the core. 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.

> Earth’s layers constantly interact with each other, and the crust and upper portion of the mantle are part of a single geologic unit called the lithosphere. The lithosphere’s depth varies, and the Mohorovicic discontinuity (the Moho)—the boundary between the mantle and crust—does not exist at a uniform depth. Isostasy describes the physical, chemical, and mechanical differences between the mantle and crust that allow the crust to “float” on the more malleable mantle. Not all regions of Earth are balanced in isostatic equilibrium. Isostatic equilibrium depends on the density and thickness of the crust, and the dynamic forces at work in the mantle.

> Just as the depth of the crust varies, so does its temperature. The upper crust withstands the ambient temperature of the atmosphere or ocean—hot in arid deserts and freezing in ocean trenches. Near the Moho, the temperature of the crust ranges from 200° Celsius (392° Fahrenheit) to 400° Celsius (752° Fahrenheit).

> Crafting the Crust

> Billions of years ago, the planetary blob that would become the Earth started out as a hot, viscous ball of rock. The heaviest material, mostly iron and nickel, sank to the center of the new planet and became its core. The molten material that surrounded the core was the early mantle.

> Over millions of years, the mantle cooled. Water trapped inside minerals erupted with lava, a process called “outgassing.” As more water was outgassed, the mantle solidified. Materials that initially stayed in their liquid phase during this process, called “incompatible elements,” ultimately became Earth’s brittle crust.

> **Comments:**
> **username_6**: From where do the quotes come? Please incorporate the reference links in the answer.  

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