Use a sedimentation curve to convert data to the time domain
Source:R/sedrate2tune.R
sedrate2tune.RdConvert a proxy record from the depth to time domain using a sedimentation rate curve
Arguments
- data
Proxy record in the depth domain (required): matrix or data frame with depth in metres in column 1 and the proxy value in column 2. Its depths need not be those of
sed_curve: the sedimentation rate is interpolated to every depth of the record.Default=NULL.- sed_curve
Sedimentation rate curve (required): matrix or data frame with depth in metres in column 1 and the sedimentation rate in cm/kyr in column 2, e.g. the output of
minimal_tuningwithoutput = 1. It is sorted, cleaned ofNArows and linearly interpolated to the depths ofdata(constant beyond its ends); the inverse rate is then integrated over depth to time (in kyr, 0 at the first sample ofdata).Default=NULL.- genplot
Plot the proxy record against time (kyr) (logical).
Default=FALSE.- keep_editable
Keep the graphical parameters of the plot after the function returns, so that extra elements can be added (logical); only used with
genplot = TRUE.Default=FALSE.
Value
The output is a matrix with 2 columns.
The first column is time
The second column is the proxy value
If genplot=TRUE then a time vs proxy value plot will be plotted.
References
Routines for astrochronologic testing, astronomical time scale construction, and time series analysis <doi:10.1016/j.earscirev.2018.11.015>
Author
Part of the code is based on the sedrate2time function of the 'astrochron' R package
Examples
# \donttest{
# Extract the 405kyr eccentricity cycle from the wavelet scalogram
# from the magnetic susceptibility record of the Sullivan core
# of Pas et al., (2018) and then create a age model using minimal tuning
# (e.g.) set the distance between peaks to 405 kyr. The age model
# (sedimentation rate curve) is then used to convert the data
# from the depth to the time domain
mag_wt <- analyse_wavelet(data = mag,
dj = 1/100,
lowerPeriod = 0.1,
upperPeriod = 254,
verbose = FALSE,
omega_nr = 10)
mag_405 <- extract_signal_stable_V2(
wavelet = mag_wt,
period_max = 4,
period_min = 2,
add_mean = TRUE,
plot_residual = FALSE,
keep_editable = FALSE
)
mag_405_min_tuning <- minimal_tuning(data = mag_405,
pts = 5,
cycle = 405,
tune_opt = "max",
output = 1,
genplot = FALSE,
keep_editable = FALSE)
mag_time <- sedrate2tune(
data=mag,
sed_curve=mag_405_min_tuning,
genplot=FALSE,
keep_editable=FALSE)
# }