“Rock formation” is an ambiguous term in this context. You pick up a rock ... when was it formed? The geologists answer is the date of the agglomeration of the material of the rock, yet in common terms, a “rock formation” refers to the apparent configuration of the constituent rocks, however ancient their “formation” may have been.
So, we’re involved in a purely rhetorical exercise. If that rock was 200 million years old, it was still 200 million years old after it was tipped over.
In this case there is nothing ambiguous about the Entrada sandstone rock formation. You are correct in terms of rhetoric, but if I demolish a car with one mile on it, would you still call it a new car?