time_bins {palaeoverse} | R Documentation |
A function to generate time bins for a given study interval and geological
timescale. This function is flexible in that either stage-level or higher
stratigraphic-level (e.g. period) time bins can be called, valid timescales
from Macrostrat can be
used, or a data.frame
of a geological timescale can be provided. In
addition, near equal-length time bins can be generated by grouping
intervals together. For example, for a target bin size of 10 Myr, the
function will generate groups of bins that have a mean bin length close to
10 Myr. However, users may also want to consider grouping stages based on
other reasoning e.g. availability of outcrop (see Dean et al. 2020).
time_bins(
interval = "Phanerozoic",
rank = "stage",
size = NULL,
assign = NULL,
scale = "GTS2020",
plot = FALSE
)
interval |
|
rank |
|
size |
|
assign |
|
scale |
|
plot |
|
This function uses either the Geological Time Scale 2020,
Geological Time Scale 2012, a valid timescale from
Macrostrat, or a
user-input data.frame
(see scale
argument) to generate time bins.
Additional information on included Geological Time Scales and source can
be accessed via:
Available interval names are accessible via the interval_name
column
in GTS2012
and GTS2020
. Data of the Geological Timescale 2020 and
2012 were compiled by Lewis A. Jones (2022-07-02).
A data.frame
of time bins for the specified intervals or a
list with a data.frame
of time bins and a named numeric
vector (bin number) of binned age estimates (midpoint of specified bins)
if assign
is specified. By default, the time bins data.frame
contains the following columns: bin, interval_name, rank, max_ma, mid_ma,
min_ma, duration_myr, abbr (interval abbreviation), colour and font
(colour). If size
is specified, the time bins data.frame
contains the following columns: bin, max_ma, mid_ma, min_ma,
duration_myr, grouping_rank, intervals, colour and font.
Dean, C.D., Chiarenza, A.A. and Maidment, S.C., 2020. Formation binning: a new method for increased temporal resolution in regional studies, applied to the Late Cretaceous dinosaur fossil record of North America. Palaeontology, 63(6), 881-901. doi:10.1111/pala.12492.
Lewis A. Jones
Kilian Eichenseer & William Gearty
#Using numeric age
ex1 <- time_bins(interval = 10, plot = TRUE)
#Using numeric age range
ex2 <- time_bins(interval = c(50, 100), plot = TRUE)
#Using a single interval name
ex3 <- time_bins(interval = c("Maastrichtian"), plot = TRUE)
#Using a range of intervals and near-equal duration bins
ex4 <- time_bins(interval = c("Fortunian", "Meghalayan"),
size = 10, plot = TRUE)
#Assign bins based on given age estimates
ex5 <- time_bins(interval = c("Fortunian", "Meghalayan"),
assign = c(232, 167, 33))
#Use user-input data.frame to generate near-equal length bins
scale <- data.frame(interval_name = 1:5,
min_ma = c(0, 18, 32, 38, 45),
max_ma = c(18, 32, 38, 45, 53))
ex6 <- time_bins(scale = scale, size = 20, plot = TRUE)
#Use North American land mammal ages from Macrostrat
ex7 <- time_bins(scale = "North American land mammal ages", size = 10)