stratcols

Introduction to the stratcols package

stratcols is an R package to handle stratigraphic columns.

Getting started

Stratigraphic columns are constructed using as_stratcol:

thickness = runif(10) #bed thicknesses
facies = rep(c(1,2), 5) # facies codes

s = as_stratcol(thickness = thickness,
                facies = facies)

The optional argument L_unit can be used to associate a length unit with the bed thicknesses. The optional argument base specifies the position of the base of the lowest bed.

is_stratcol can be used to test if any object is a valid stratigraphic column:

is_stratcol(s)
#> [1] TRUE

Bed thicknesses can be extracted using bed_thickness:

bed_thickness(s)
#>  [1] 0.32054099 0.08676281 0.88663607 0.64754478 0.03600257 0.77507390
#>  [7] 0.16724082 0.76026262 0.92381073 0.69849859

You can extract (unique) facies names as follows:

facies_names(s)
#>  [1] 1 2 1 2 1 2 1 2 1 2
unique_facies_names(s)
#> [1] 1 2

Further functionality includes

no_beds(s) # number of beds
#> [1] 10
no_facies(s) # number of distinct facies.
#> [1] 2

total_thickness(s) # total thickness of column
#> [1] 5.302374

get_base(s) # lowest bed boundary
#> [1] 0
get_L_unit(s) # length unit of beds
#> NULL

facies_repetitions(s) # do at least two successive beds have identical facies?
#> [1] FALSE
merge_beds(s, mode = "identical facies") # merge successive beds with identical facies
#> Stratigraphic column

Plotting stratigraphic columns

stratcols wraps StratigrapheR to plot stratigraphic columns. Facies codes are interpreted as hardness

plot(s)

Modifying stratigraphic columns

Facies names can be changed using rename_facies:

s2 = rename_facies(s, new_names = c(2,3))
plot(s2)

The optional argument old_names can be used to replace specific facies.

You can assign a stratigraphic column a length unit using

s3 = set_L_unit(s, "m")
get_L_unit(s3)
#> [1] "m"

Further reading

See

vignette("stratcols_doc")

for an explanation of the larger structure of the package and definitions of the classes.

See

vignette("stratorder")

for available methods to estimate stratigraphic order metrics, such as the runs order metric (ROM) and the Markov order metric (MOM).