Which preposition to use with stratifications

of Occurrences 9%

A sandwich was a stratification of bread and meat by the Earl of Sandwich, who was so loath to leave the gaming table that he saved time by having food brought him in this form.

in Occurrences 1%

In other words, there is a sort of rough and incomplete stratification in the lump of coal, as if it were a book, the leaves of which had stuck together very closely.

on Occurrences 1%

This stone, though so compact in the recent fracture, has distinct traces of stratification on the decomposed surface, which is of a dull reddish hue.

Which preposition to use with  stratifications