timetostratratecont: Transform Patterns from Time into Stratigraphic Height (Continuous)

Description

This function transforms a given continuous temporal pattern into the corresponding stratigraphic pattern. The transformation is based on the age model derived from the given deposition rate. Essentially a wrapper of patterntransform(...,direction='time to height',depositionmodel='piecewise linear deposition rate',patternmode='piecewise linear') kept for backwards compatibility of the package. It is recommended to use patterntransform instead of this function.

Usage

timetostratratecont(xdep, ydep, xsig, ysig, pos = NULL)

Arguments

xdep

Vector of strictly increasing real numbers

ydep

Vector of the same length of xdep, containing strictly positive real numbers. xdep and ydep define the deposition rate in the sense that depositionrate=approxfun(xdep,ydep)

xsig

Vector of strictly increasing real numbers

ysig

Vector of the same length of xsig, containing positive real numbers. xsig and ysig define the temporal pattern in the sense that temporalpat=approxfun(xsig,ysig).

pos

OPTIONAL. Vector of points in time height that will be transformed into stratigraphic height, and determine where the stratigraphic pattern is evaluated. Default setting is a vector spanning the interval of interest with evenly spaced points (no. is chosen by the code)

Value

Returns a list containing:

height

vector containing stratigraphic heights

val

vector containign the values of the stratigraphic pattern at height

The stratigraphic pattern can be approximated using stratpat=approxfun(height,val)

References

Hohmann, Niklas. 2018. Quantifying the Effects of Changing Deposition Rates and Hiatii on the Stratigraphic Distribution of Fossils. <doi:10.13140/RG.2.2.23372.51841>

Examples

Run this code

# NOT RUN {
##define deposition rate
xdep=seq(0,12,length.out=100)
ydep=splinefunH(x=c(0,2,4,6,8,10,12),y=c(1,5,6,1,0.5,1,6),m=c(0,1.5,-0.5,-0.5,0,0.5,0))(xdep)
#Plot deposition rate
plot(xdep,ydep,type='l',main='Deposition Rate',xlab='Time',ylab='Sediment per Time Unit')

#define a temporal pattern
xsig= seq(0,12,length.out=100)
ysig=splinefunH(x=c(0,4,12),y=c(0.5,2,0.5),m=c(0,0,0))(xsig)
plot(xsig,ysig,type='l',main='Temporal Pattern',xlab='Time',ylab='Intensity')

##transform temporal pattern into stratigraphic pattern (pattern observable in the section)
reslist=timetostratratecont(xdep,ydep,xsig,ysig)
plot(reslist$height,reslist$val,type='l',xlab='Stratigraphic Height',
  ylab='Intensity',main='Stratigraphic Pattern')
  
##with removal of sediment
ydep=splinefunH(x=c(0,2,4,6,8,10,12),y=c(1,5,6,-2,5,1,6),m=c(0,1.5,-0.5,-0.5,0,0.5,0))(xdep)
#Plot deposition rate
plot(xdep,ydep,type='l',main='Deposition Rate',xlab='Time',ylab='Sediment per Time Unit')
reslist=timetostratratecont(xdep,ydep,xsig,ysig)
plot(reslist$height,reslist$val,type='l',xlab='Stratigraphic Height',
  ylab='Intensity',main='Stratigraphic Pattern',ylim=c(0,1))
#the spike is because the deposition rate is very small when it transitions from 
#negative to positive, generating a punctual extreme condensation
  
# }