A radiocarbon review:
Apps, databases, calibrations and analysis
Apps, databases, calibrations and analysis
Thomas Huet
Radiocarbon ressources
Today exists various web-based ressources for database, calibrations, interactive selection and spatialization and analysis
Applications
| names | url |
|---|---|
| MedAfriCarbon | https://theia.arch.cam.ac.uk/MedAfriCarbon/ |
| NeoNet | https://zoometh.github.io/C14/neonet |
| EUROEVOL_R | https://neolithic.shinyapps.io/Euroevol_R/ |
MedAfriCarbon, NeoNet and EUROEVOL_R allow interactive web form map-based for of radiocarbon dates selection by geographical region of interest, time span and periods, quality of the date, etc. These apps offer also analysis tools like summing probability densities (SPD).
These apps have been developped with R programming language and the Shiny package
MedAfriCarbon
- MedAfriCarbon app covers the South Mediterranean between the beginning of the Holocene ) and the arrival of Phoenicians and Greeks (ca. 9,600 - 600 BC) with near 1,600 radiocarbon dates
The MedAfriCarbon offers an almost complete toolbox to manage radiocarbon dates
NeoNet and EUROEVOL_R
NeoNet and EUROEVOL_R share the same layout, mostly inherited from the EUROEVOL database, only the datasets are differents
- NeoNet app covers the Northern Central Mediterranean between the Late Mesolithic and Middle Neolithic (ca. 8,000 - 4,500 BC) with near to 1,500 radiocarbon dates
The database, an Excel Sheet, see the NeoNet app webpage
- EUROEVOL_R app covers the Central, Western and Northern Europe from Paleolithic times to the end of Bronze Age (ca. 17,000 - 500 BC) with near to 14,000 radiocarbon dates
The app database is the EUROEVOL database, is opensource and static (yet developed), see the EUROEVOL_R app webpage
Databases
An almost exhaustive inventory of open databases has been made on the c14bazAAR repository
| names | url |
|---|---|
| EUROEVOL | http://discovery.ucl.ac.uk/1469811 |
| Radon | https://radon.ufg.uni-kiel.de/ |
| ORAU | https://c14.arch.ox.ac.uk |
| telearchaeology | http://telearchaeology.org/c14-databses/ |
| Archaeological Site Index to Radiocarbon Dates from Great Britain and Ireland | http://www.britarch.ac.uk/info/c14.html |
| 14SEA Project | http://www.14sea.org/2_dates.html |
| EX ORIENTE | https://www.exoriente.org/associated_projects/ppnd_sites.php |
| BANADORA | http://www.archeometrie.mom.fr/banadora/ |
Get data
R progamming language permits to download radiocarbon data from databases.
| type | names | url |
|---|---|---|
| R programming | c14bazAAR | https://github.com/ropensci/c14bazAAR |
| dedicated | GoGet | https://www.ibercrono.org/goget/index.php |
The c14bazAAR package allows to browse different database. As an example, let’s load the the Radon database:
## Trying to download all dates from the requested databases...##
|
| | 0%
|
|++++++++++++++++++++++++++++++++++++++++++++++++++| 99%
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|++++++++++++++++++++++++++++++++++++++++++++++++++| 100%And retrieve a radiocarbon data (site, c14age, c14std, etc.) from its LabCode. For example, let’s choose the ‘Ly-11645’ LabCode:
# function to retrieve main info from a date
f.info.a.date <- function(a.db, a.dat){
col.nmes <- c("site", "labnr","c14age","c14std", "shortref")
df <- a.db[a.db$labnr == a.dat, col.nmes]
df <- as.data.frame(df[!is.na(df$labnr), ])
return(df)
}
# run
f.info.a.date(radonC14, 'Ly-11645')## site labnr c14age c14std shortref
## 1 Gazel Grotte Ly-11645 6035 85 <NA>Calibrations
| type | names | url |
|---|---|---|
| dedicated | OxCal | https://c14.arch.ox.ac.uk/oxcal/ |
| dedicated | CalPal | http://www.calpal-online.de/ |
| dedicated | Calib | http://calib.org/calib/ |
| R programming | rcarbon | https://cran.r-project.org/web/packages/rcarbon/index.html |
| R programming | Bchron | https://cran.r-project.org/web/packages/Bchron/index.html |
| R programming | oxcAAR | https://cran.r-project.org/web/packages/oxcAAR/index.html |
Analysis
R offers a comprehensive framework to calibrate, plot, sum and use temporal constraints – stratigraphy, periodisations, etc., like bayesian analysis – on radiocarbon datasets. Free software offering a dedicated solution for bayesian inference are: ChronoModel, OpenBUGS, JAGS, etc.
For a overview of the available solutions, see the R Bayesian task view