enumerates the facies according to their order of appearance (counting from the bottom of the section). To be applied to stratigraphic columns before get_mom is called. Replaces the facies codes by integer numbers
Examples
s = as_stratcol(c(0.5, 1, 0.3, 0.7), c("sand", "shale", "sand", "clay"), L_unit = "m")
s = order_facies_names(s)
plot(s)