timetostratratecont {DAIME}R Documentation

Transform Rates from Time into Stratigraphic Height (Continuous)

Description

This function transforms a given continuous temporal rate/signal into the corresponding stratigraphic rate/signal. The transformation is based on the age model constructed from the deposition rate.

This can for example be used to predict the patterns of (first/last) fossil occurrences in the outcrop under a given depositional environment.

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 rate in the sense that stratigraphicrate=approxfun(xsig,ysig).

pos

OPTIONAL. Vector of points in time height that will be transformed into stratigraphic height, and determine where the stratigraphic rate 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

x

vector containing stratigraphic heights (that are deposited at times xdep (pos if used))

y

vector containign the values of the stratigraphic rate/signal at x

x and y define the stratigraphic rate/signal in the sense that stratsig=approxfun(x,y)

Author(s)

Niklas Hohmann

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>

See Also

strattotimeratecont for the transformation of rates from stratigraphic height into time, timetostratpointcont for the transformation of sigle samples or isotope ratios from time into stratigraphic height.

For an overview of the functions in the DAIME package, see its vignette (available via vignette("DAIME") )

Examples

##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 rate ("signal")
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 Signal/Rate',xlab='Time',ylab='Signal Intensity')

##transform temporal rate into stratigraphic rate (signal observable in the section)
reslist=timetostratratecont(xdep,ydep,xsig,ysig)
plot(reslist$height,reslist$val,type='l',xlab='Stratigraphic Height',
  ylab='Signal Intensity',main='Stratigraphic Rate/Signal')
  
##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='Signal Intensity',main='Stratigraphic Rate/Signal',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
  

[Package DAIME version 1.1 Index]