Explanation:

formations are as old as 3,200 million years.
This can be explained through sea-floor spreading. Constant eruptions at the crest of oceanic ridges cause the rupture of the oceanic crust and the The age of rocks in the oceanic crust is nowhere more than 200 million years old. Some of the continental rock new lava wedges into it, pushing the oceanic crust on either side. The ocean floor thus spreads. The younger age of the oceanic crust as well as the fact that the spreading of one ocean does not cause the shrinking of the other explains the consumption of the oceanic crust. The ocean floor that gets pushed due to volcanic eruptions at the crest sinks down at the oceanic trenches and gets consumed.