How does the age of the oldest continental crust compared to the age of the oldest ocean crust apex?

The oldest continental crust compared to the oldest oceanic crust is incomparably much older. This is because the continental crust is much denser, and when there's a collision between the tectonic plates it is not pushed downwards towards the mantle, and thus being recycled, but instead manages to remain on the surface (especially in the middle of the continents), like in some parts of Australia, Canada, Siberia, Central Africa. On the other hand, the oceanic crust is much less dense, so when the tectonic plates collide it is subducted, thus going down in the mantle and being melted and recycled.

answer conditional instability;