astro_anchor {WaverideR}R Documentation

Anchor proxy record to an astronomical solution

Description

Anchor the extracted signal to an astronomical solution using a GUI. The astro_anchor function allows one to tie minima or maxima in the proxy record to minima or maxima in an astronomical solution. By tying the proxy record to an astronomical solution one will generate tie-points which can be used to generate a astrochronological age-model As minima or maxima in the proxy record are tied to minima or maxima in an astronomical solution it is important to provide input which has clearly definable minima and maxima. As such input should be of a "sinusoidal" nature otherwise the extract_astrosolution=TRUE and/or extract_proxy_signal=TRUE options need to be set to TRUE to create sinusoidal signals.

Astronomical solutions option are:

Usage

astro_anchor(
  astro_solution = NULL,
  proxy_signal = NULL,
  proxy_min_or_max = "max",
  clip_astrosolution = FALSE,
  astrosolution_min_or_max = "max",
  clip_high = NULL,
  clip_low = NULL,
  extract_astrosolution = FALSE,
  astro_period_up = 1.2,
  astro_period_down = 0.8,
  astro_period_cycle = NULL,
  extract_proxy_signal = FALSE,
  proxy_period_up = 1.2,
  proxy_period_down = 0.8,
  proxy_period_cycle = NULL,
  pts = 3,
  verbose = FALSE,
  time_dir = TRUE,
  genplot = FALSE
)

Arguments

astro_solution

Input is an astronomical solution which the proxy record will be anchored to, the input should be a matrix or data frame with the first column being age and the second column should be a insolation/angle/value

proxy_signal

Input is the proxy data set which will be anchored to an astronomical solution, the input should be a matrix or data frame with the first column being depth/time and the second column should be a proxy value. For the best results either the astronomical components need to be pre-extracted before anchoring. This means that a filtering/cycle extracting need to be applied to the input data or the extract_proxy_signal option needs to be set to TRUE.

proxy_min_or_max

Tune proxy maxima or minima to the astronomical solution Default="max".

clip_astrosolution

Clip the astronomical solution Default=FALSE.

astrosolution_min_or_max

Tune to maximum or minimum values of the astronomical solution Default="max"

clip_high

Upper value to clip to.

clip_low

Lower value to clip to.

extract_astrosolution

Extract a certain astronomical cycle/component from a astronomical solution prior to anchoring Default=FALSE.

astro_period_up

Specifies the upper period of the astronomical cycle which is extracted from an astronomical solution. The astro_period_up is a factor with which the astronomical component is multiplied by. Default=1.2

astro_period_down

Specified the lower period of the astronomical cycle which is extracted from an astronomical solution. The astro_period_down value is a factor with which the astronomical component is multiplied by. Default=0.8

astro_period_cycle

Period (in kyr) of the to be extracted astronomical component from the astronomical solution.

extract_proxy_signal

Extract a certain astronomical cycle/component from a proxy signal Default=FALSE.

proxy_period_up

Specifies the upper period of the astronomical cycle to be extracted from the proxy record. The upper bound value is a factor with which the (proxy_period_cycle) value is multiplied by. Default=1.2.

proxy_period_down

Specifies the upper period of the astronomical cycle to be extracted from the proxy record. The lower bound value is a factor with which the astronomical component (proxy_period_cycle) value is multiplied by. Default=0.8.

proxy_period_cycle

Period in kyr of the astronomical cycle/component which is to be extracted from the proxy record.

pts

The pts parameter specifies how many points to the left/right up/down the peak detect algorithm goes in detecting a peak. The peak detecting algorithm works by comparing the values left/right up/down of it, if the values are both higher or lower then the value a peak. To deal with error produced by this algorithm the pts parameter can be changed which can aid in peak detection. Usually increasing the pts parameter means more peak certainty, however it also means that minor peaks might not be picked up by the algorithm Default=3

verbose

print text Default=FALSE set verbose to TRUE to allow for anchoring using text feedback commands

time_dir

The direction of the proxy record which is assumed for tuning if time increases with increasing depth/time values (e.g. bore hole data which gets older with increasing depth ) then time_dir should be set to TRUE if time decreases with depth/time values (eg stratigraphic logs where 0m is the bottom of the section) then time_dir should be set to FALSE time_dir=TRUE

genplot

Generate plot Default="FALSE"

Value

The output is a matrix with the 4 columns. The first column is the depth/time of the proxy tie-point. The second column is the time value of the astronomical solution tie-point. The third column is the proxy value of the proxy tie-point. The fourth column is the proxy/insolation value of the astronomical solution tie-point. If genplot is set to true then at plot of the of the achored points will be plotted

References

J. Laskar, P. Robutel, F. Joutel, M. Gastineau, A.C.M. Correia, and B. Levrard, B., 2004, A long term numerical solution for the insolation quantities of the Earth: Astron. Astrophys., Volume 428, 261-285. <doi:10.1051/0004-6361:20041335>

Laskar, J., Fienga, A., Gastineau, M., Manche, H., 2011a, La2010: A new orbital solution for the long-term motion of the Earth: Astron. Astrophys., Volume 532, A89 <doi:10.1051/0004-6361/201116836>

Laskar, J., Gastineau, M., Delisle, J.-B., Farres, A., Fienga, A.: 2011b, Strong chaos induced by close encounters with Ceres and Vesta, Astron: Astrophys., Volume 532, L4. <doi:10.1051/0004-6361/201117504>

J. Laskar,Chapter 4 - Astrochronology,Editor(s): Felix M. Gradstein, James G. Ogg, Mark D. Schmitz, Gabi M. Ogg,Geologic Time Scale 2020,Elsevier,2020,Pages 139-158,ISBN 9780128243602, <doi:10.1016/B978-0-12-824360-2.00004-8> or https://www.sciencedirect.com/science/article/pii/B9780128243602000048

Zeebe, R. E. and Lourens, L. J. Geologically constrained astronomical solutions for the Cenozoic era, Earth and Planetary Science Letters, 2022 <doi:10.1016/j.epsl.2022.117595>

Richard E. Zeebe Lucas J. Lourens ,Solar System chaos and the Paleocene–Eocene boundary age constrained by geology and astronomy.Science365,926-929(2019) <doi:10.1126/science.aax0612>

Zeebe, Richard E. "Numerical solutions for the orbital motion of the Solar System over the past 100 Myr: limits and new results." The Astronomical Journal 154, no. 5 (2017): 193. <doi:10.3847/1538-3881/aa8cce>

Stephen R. Meyers,Cyclostratigraphy and the problem of astrochronologic testing, Earth-Science Reviews,Volume 190,2019,Pages 190-223,ISSN 0012-8252 <doi:10.1016/j.earscirev.2018.11.015>

Examples


# Use the grey_track example tracking points to anchor the grey scale data set
# of Zeeden et al., (2013) to the p-0.5t la2004 solution

grey_wt <-
 analyze_wavelet(
   data = grey,
   dj = 1/200,
   lowerPeriod = 0.02,
   upperPeriod = 256,
   verbose = FALSE,
   omega_nr = 8
 )
#Use the pre-tracked grey_track curve which traced the precession cycle
grey_track <- completed_series(
 wavelet = grey_wt,
 tracked_curve  = grey_track,
 period_up  = 1.25,
 period_down  = 0.75,
 extrapolate = TRUE,
genplot = FALSE
)
# Extract precession, obliquity and eccentricity to create a synthetic insolation curve

grey_prec <- extract_signal(
tracked_cycle_curve = grey_track[,c(1,2)],
wavelet = grey_wt,
period_up = 1.2,
period_down = 0.8,
add_mean = FALSE,
tracked_cycle_period = 22,
extract_cycle = 22,
tune = FALSE,
plot_residual = FALSE
)

grey_obl <- extract_signal(
 tracked_cycle_curve = grey_track[,c(1,2)],
 wavelet = grey_wt,
 period_up = 1.2,
 period_down = 0.8,
 add_mean = FALSE,
 tracked_cycle_period = 22,
 extract_cycle = 110,
 tune = FALSE,
 plot_residual = FALSE
)

grey_ecc <- extract_signal(
 tracked_cycle_curve = grey_track[,c(1,2)],
 wavelet = grey_wt,
 period_up = 1.25,
 period_down = 0.75,
 add_mean = FALSE,
 tracked_cycle_period = 22,
 extract_cycle = 40.8,
 tune = FALSE,
 plot_residual = FALSE
)

insolation_extract <- cbind(grey_ecc[,1],grey_prec[,2]+grey_obl[,2]+grey_ecc[,2]+mean(grey[,2]))
insolation_extract <- as.data.frame(insolation_extract)
insolation_extract_mins <- min_detect(insolation_extract,pts=3)

#use the astrosignal_example to tune to which is an \cr
# ETP solution (p-0.5t la2004 solution)
astrosignal_example <- na.omit(astrosignal_example)
astrosignal_example[,2] <- -1*astrosignal_example[,2]
astrosignal <- as.data.frame(astrosignal_example)

#anchor the synthetic insolation curve extracted from the grey scale record to the insolation curve.

anchor_pts <- astro_anchor(
astro_solution = astrosignal,
proxy_signal = insolation_extract,
proxy_min_or_max = "min",
clip_astrosolution = FALSE,
astrosolution_min_or_max = "min",
clip_high = NULL,
clip_low = NULL,
extract_astrosolution  = FALSE,
astro_period_up  = NULL,
astro_period_down  = NULL,
astro_period_cycle  = NULL,
extract_proxy_signal  = FALSE,
proxy_period_up  = NULL,
proxy_period_down  = NULL,
proxy_period_cycle  = NULL,
pts=3,
verbose=FALSE, #set verbose to TRUE to allow for anchoring using text feedback commands
genplot=FALSE
)
[Package WaverideR version 0.3.2 Index]