Which coastline of south america is nearest to the oldest seafloor? eastern, western, or southern tip

I believe the answer is on the Eastern coastline.
Currently, the oldest seafloor is around 280 million years old and  is found in the north-eastern the north-eastern Pacific Ocean,  and Atlantic Ocean 
Comparatively, this is very young because the oldest continental rock is recorded at 4 billion years old.

Answeris associated with sunny,dry weather;