For reference :
Walther's Law of Facies, or simply Walther's Law, named after the geologist Johannes Walther (1860-1937), states that the vertical succession of facies reflects lateral changes in environment. Conversely, it states that when a depositional environment "migrates" laterally, sediments of one depositional environment come to lie on top of another.[4] In Russia the law is known as Golovkinsky-Walther's Law, honoring also Nikolai A. Golovkinsky[5] (1834-1897). A classic example of this law is the vertical stratigraphic succession that typifies marine transgressions and regressions.
Wikipedia
Let me repeat that last sentence:
A classic example of this law is the vertical stratigraphic succession that typifies marine transgressions and regressions.