The hardware and bandwidth for this mirror is donated by dogado GmbH, the Webhosting and Full Service-Cloud Provider. Check out our Wordpress Tutorial.
If you wish to report a bug, or if you are interested in having us mirror your free-software or open-source project, please feel free to contact us at mirror[@]dogado.de.

ShellChron: Builds Chronologies from Oxygen Isotope Profiles in Shells

Takes as input a stable oxygen isotope (d18O) profile measured in growth direction (D) through a shell + uncertainties in both variables (d18O_err & D_err). It then models the seasonality in the d18O record by fitting a combination of a growth and temperature sine wave to year-length chunks of the data (see Judd et al., (2018) <doi:10.1016/j.palaeo.2017.09.034>). This modeling is carried out along a sliding window through the data and yields estimates of the day of the year (Julian Day) and local growth rate for each data point. Uncertainties in both modeling routine and the data itself are propagated and pooled to obtain a confidence envelope around the age of each data point in the shell. The end result is a shell chronology consisting of estimated ages of shell formation relative to the annual cycle with their uncertainties. All formulae in the package serve this purpose, but the user can customize the model (e.g. number of days in a year and the mineralogy of the shell carbonate) through input parameters.

Version: 0.4.0
Depends: R (≥ 3.5.0)
Imports: rtop (≥ 0.5.14), zoo (≥ 1.8.7), ggplot2 (≥ 3.2.1), ggpubr (≥ 0.4.0), tidyr (≥ 1.1.1), scales (≥ 1.1.0), dplyr, magrittr
Suggests: knitr, rmarkdown
Published: 2021-07-05
DOI: 10.32614/CRAN.package.ShellChron
Author: Niels de Winter ORCID iD [aut, cre]
Maintainer: Niels de Winter <niels_de_winter at live.nl>
BugReports: https://github.com/nielsjdewinter/ShellChron/issues
License: GPL-3
URL: https://github.com/nielsjdewinter/ShellChron
NeedsCompilation: no
Materials: README NEWS
CRAN checks: ShellChron results

Documentation:

Reference manual: ShellChron.pdf

Downloads:

Package source: ShellChron_0.4.0.tar.gz
Windows binaries: r-devel: ShellChron_0.4.0.zip, r-release: ShellChron_0.4.0.zip, r-oldrel: ShellChron_0.4.0.zip
macOS binaries: r-release (arm64): ShellChron_0.4.0.tgz, r-oldrel (arm64): ShellChron_0.4.0.tgz, r-release (x86_64): ShellChron_0.4.0.tgz, r-oldrel (x86_64): ShellChron_0.4.0.tgz
Old sources: ShellChron archive

Linking:

Please use the canonical form https://CRAN.R-project.org/package=ShellChron to link to this page.

These binaries (installable software) and packages are in development.
They may not be fully stable and should be used with caution. We make no claims about them.
Health stats visible at Monitor.