ExampleData.SurfaceExposure {Luminescence}

Example OSL surface exposure dating data

Description

A set of synthetic OSL surface exposure dating data to demonstrate the fit_SurfaceExposure functionality. See examples to reproduce the data interactively.

Format

A list with 4 elements:

Element	Content
⁠$sample_1⁠	A data.frame with 3 columns (depth, intensity, error)
⁠$sample_2⁠	A data.frame with 3 columns (depth, intensity, error)
⁠$set_1⁠	A list of 4 data.frames, each representing a sample with different ages
⁠$set_2⁠	A list of 5 data.frames, each representing a sample with different ages

Details

⁠$sample_1⁠

mu	sigmaphi	age
0.9	5e-10	10000

⁠$sample_2⁠

mu	sigmaphi	age	Dose rate	D0
0.9	5e-10	10000	2.5	40

⁠$set_1⁠

mu	sigmaphi	ages
0.9	5e-10	1e3, 1e4, 1e5, 1e6

⁠$set_2⁠

mu	sigmaphi	ages	Dose rate	D0
0.9	5e-10	1e2, 1e3, 1e4, 1e5, 1e6	1.0	40

Source

See examples for the code used to create the data sets.

References

Unpublished synthetic data

Examples

## ExampleData.SurfaceExposure$sample_1
sigmaphi <- 5e-10
age <- 10000
mu <- 0.9
x <- seq(0, 10, 0.1)
fun <- exp(-sigmaphi * age * 365.25*24*3600 * exp(-mu * x))

set.seed(666)
synth_1 <- data.frame(depth = x,
                      intensity = jitter(fun, 1, 0.1),
                      error = runif(length(x), 0.01, 0.2))

## VALIDATE sample_1
fit_SurfaceExposure(synth_1, mu = mu, sigmaphi = sigmaphi)




## ExampleData.SurfaceExposure$sample_2
sigmaphi <- 5e-10
age <- 10000
mu <- 0.9
x <- seq(0, 10, 0.1)
Ddot <- 2.5   / 1000 / 365.25 / 24 / 60 / 60 # 2.5 Gy/ka in Seconds
D0 <- 40
fun <- (sigmaphi * exp(-mu * x) *
          exp(-(age * 365.25*24*3600) *
                (sigmaphi * exp(-mu * x) + Ddot/D0)) + Ddot/D0) /
  (sigmaphi * exp(-mu * x) + Ddot/D0)

set.seed(666)
synth_2 <- data.frame(depth = x,
                      intensity = jitter(fun, 1, 0.1),
                      error = runif(length(x), 0.01, 0.2))

## VALIDATE sample_2
fit_SurfaceExposure(synth_2, mu = mu, sigmaphi = sigmaphi, Ddot = 2.5, D0 = D0)



## ExampleData.SurfaceExposure$set_1
sigmaphi <- 5e-10
mu <- 0.9
x <- seq(0, 15, 0.2)
age <- c(1e3, 1e4, 1e5, 1e6)
set.seed(666)

synth_3 <- vector("list", length = length(age))

for (i in 1:length(age)) {
  fun <- exp(-sigmaphi * age[i] * 365.25*24*3600 * exp(-mu * x))
  synth_3[[i]] <- data.frame(depth = x,
                             intensity = jitter(fun, 1, 0.05))
}


## VALIDATE set_1
fit_SurfaceExposure(synth_3, age = age, sigmaphi = sigmaphi)



## ExampleData.SurfaceExposure$set_2
sigmaphi <- 5e-10
mu <- 0.9
x <- seq(0, 15, 0.2)
age <- c(1e2, 1e3, 1e4, 1e5, 1e6)
Ddot <- 1.0 / 1000 / 365.25 / 24 / 60 / 60 # 2.0 Gy/ka in Seconds
D0 <- 40
set.seed(666)

synth_4 <- vector("list", length = length(age))

for (i in 1:length(age)) {
  fun <- (sigmaphi * exp(-mu * x) *
            exp(-(age[i] * 365.25*24*3600) *
                  (sigmaphi * exp(-mu * x) + Ddot/D0)) + Ddot/D0) /
    (sigmaphi * exp(-mu * x) + Ddot/D0)

  synth_4[[i]] <- data.frame(depth = x,
                             intensity = jitter(fun, 1, 0.05))
}


## VALIDATE set_2
fit_SurfaceExposure(synth_4, age = age, sigmaphi = sigmaphi, D0 = D0, Ddot = 1.0)

## Not run: 
ExampleData.SurfaceExposure <- list(
  sample_1 = synth_1,
  sample_2 = synth_2,
  set_1 = synth_3,
  set_2 = synth_4
)

## End(Not run)