An observable process I can show here is where sand pictures sort sand into layers making art as show below in the videos.
And there is also a repeatable mechanism for horizontal layering. This is also testable and repeatable with the same results which makes it empirical. Here is a video demonstrating this.
So we have repeatable (empirical) mechanisms for both horizontal and vertical layering. Mechanism which support the flood causing the layering, not millions of years.