Here's a breakdown:
Continental Crust:
* Average thickness: 35 km (22 miles)
* Range: 25-70 km (16-43 miles)
* Thicker areas: Mountain ranges like the Himalayas can have crust up to 70 km thick.
* Thinner areas: Regions like the Great Plains may have crust as thin as 25 km.
Oceanic Crust:
* Average thickness: 7 km (4 miles)
* Range: 5-10 km (3-6 miles)
* Thicker areas: Areas near mid-ocean ridges, where new crust is formed, can be slightly thicker.
* Thinner areas: Older oceanic crust, which is further away from mid-ocean ridges, tends to be thinner.
Key Differences:
* Composition: Continental crust is mostly composed of granite, while oceanic crust is mostly composed of basalt.
* Density: Oceanic crust is denser than continental crust.
* Age: Oceanic crust is constantly being recycled at subduction zones, making it generally younger than continental crust.
So, there isn't a single answer to the question of crust thickness. It depends on the type of crust and its location.
