Package: ShellChron
Title: Builds Chronologies from Oxygen Isotope Profiles in Shells
Version: 0.4.1
Authors@R: 
    person(given = "Niels",
           family = "de Winter",
           role = c("aut", "cre"),
           email = "niels_de_winter@live.nl",
           comment = c(ORCID = "0000-0002-1453-5407"))
Description: 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.
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
License: GPL-3
URL: https://github.com/nielsjdewinter/ShellChron
BugReports: https://github.com/nielsjdewinter/ShellChron/issues
Encoding: UTF-8
LazyData: true
Roxygen: list(markdown = TRUE)
RoxygenNote: 7.2.1
Depends: R (>= 3.5.0)
Suggests: knitr, rmarkdown
Config/pak/sysreqs: libabsl-dev cmake libgdal-dev gdal-bin libgeos-dev
        make libicu-dev libssl-dev libproj-dev libsqlite3-dev
        libudunits2-dev
Repository: https://nielsjdewinter.r-universe.dev
Date/Publication: 2022-08-18 13:57:00 UTC
RemoteUrl: https://github.com/nielsjdewinter/shellchron
RemoteRef: HEAD
RemoteSha: ac2ecdddd0cd1616e60b3711f6b2cbca56abc411
NeedsCompilation: no
Packaged: 2026-07-04 18:29:54 UTC; root
Author: Niels de Winter [aut, cre] (ORCID:
    <https://orcid.org/0000-0002-1453-5407>)
Maintainer: Niels de Winter <niels_de_winter@live.nl>