Data Quality

Data on dune chronology have been generated by many different investigators in an environment in which the dating techniques and analysis methods have been evolving rapidly and will continue to change.  The database therefore includes metadata to allow quality-control issues to be dealt with objectively. The goal is to provide metadata that will allow current and future users of the database to evaluate the information it contains.    Metadata categories developed by the INQUA Project Group for luminescence dates include details of the type of luminescence used (e.g. TL, IRSL, OSL); the luminescence protocols adopted; any corrections, and the age model adopted.   Similar metadata are included for radiocarbon dates. Users of the database also need to be aware of the confidence level that can be placed on the age information.  The INQUA project group has developed five categories of data, as follows (luminescence example given):

Category 0:     No location information, but ages reported

Category 1:     Sample location (Latitude and Longitude) and age reported 

Category 2:     Above information, plus data on sample depth, laboratory and/or sample number, luminescence error, and luminescence type

Category 3:     Above information, plus data on the mineral and grain size dated, and the dating protocol and corrections used

Category 4:     Above information, plus use of SAR and SGR techniques with quality control, and age model reported.