Ozone is away from crust. It founds suitable conditions for formation there.
Yes, the crust is the top layer. It continually changes.
Crust
half of earths layer
crust
The earth thinnest layer is the crust.
The crust is the thinnest layer of the Earth.
The crust
The crust.
The crust, more specifically the lithosphere.
continental crust
mantle
The crust.