srnd {GCDkit}R Documentation

Recalculations of the Sr-Nd isotopic data

Description

Age-corrects the Sr-Nd isotopic data to a given age; calculates initial ε(Nd) values and Nd model ages.

Usage

    srnd(age = NULL)

    initial(age = NULL, x = WR, system = "Nd")

    epsilon(age, x = WR)

    DMage(x = WR)

    DMGage(x = WR)

    DMLHage(age = NULL, x = WR, RCC = 0.12)

Arguments

age

age in Ma.

x

numeric matrix with isotopic data to be recalculated.

system

character; which isotopic system: Sr or Nd?

RCC

numeric; the 147Sm/144Nd ratio of the intermediate crustal reservoir for calculation of the two-stage Nd model ages.

Details

Recalculates the Sr-Nd isotopic data and returns them in the numeric matrix init with the following columns (DM = Depleted Mantle):

Age (Ma) Age in Ma
87Sr/86Sri Initial 87Sr/86Sr ratios
143Nd/144Ndi Initial 143Nd/144Nd ratios
EpsNdi Initial ε(Nd) values
TDM Single-stage DM Nd model ages (Liew & Hofmann, 1988), function DMage
TDM.Gold Single-stage DM Nd model ages (Goldstein et al., 1988), function DMGage
TDM.2stg Two-stage DM Nd model ages (Liew & Hofmann, 1988), function DMLHage

If the parameter age in call to the main function srnd() is empty, and no column named Age is found in the dataset, the user is prompted to enter a value. For other functions, the argument age is empty, it is taken from the value assigned upon loading the dataset.

Value

For srnd():

init

numeric matrix with the results

age

numeric vector with the ages used in calculations for each sample

For all functions:

results

numeric matrix, or vector, with the results

Plugin

SrNd.r

Author(s)

Vojtěch Janoušek, vojtech.janousek@geology.cz

References

Goldstein SL, O'Nions RK & Hamilton PJ (1984) A Sm-Nd isotopic study of atmospheric dusts and particulates from major river systems. Earth Planet Sci Lett 70: 221-236 doi: 10.1016/0012-821X(84)90007-4

Liew TC & Hofmann AW (1988) Precambrian crustal components, plutonic associations, plate environment of the Hercynian Fold Belt of Central Europe: indications from a Nd and Sr isotopic study. Contrib Mineral Petrol 98: 129-138 doi: 10.1007/BF00402106

See Also

elemIso, reciprocalIso, ageEps,

epsEps, isochron,

boxplotIso, stripplotIso,

addResultsIso, saveResultsIso

Examples

    data(blatna_iso)
    accessVar("blatna_iso")
    
    srnd() # Using the age information from the file; 
    # This is done automatically upon loading a new data file.
    
    srnd(500)
    
    initial(346,system="Sr")

    out<-cbind(epsilon(0),epsilon(346))
    colnames(out)<-c(0,346)
    print(out)
    
    DMage()

    DMGage()

    DMLHage()

[Package GCDkit version 6.1 Index]