Entries in this tree control the available options in the Chronostrat and Biostrat fields in the Paleo Context section of the main data entry form.
The Chronostratigraphy tree shows the names of geologic time in a nested format. Erathem/Era, System/Period, Series/Epoch, Sub-System/Period and Stage/Age are formal divisions. Sub-Series/Epoch was added to allow for handling data from historic databases.
The Chronostrat tree shows the relationships of these divisions. Expanding the Cenozoic (an Erathem/Era), we see it contains 3 Systems/Periods- Neogene, Paleogene and Quaternary. These Periods can be expanded to show which Series/Epochs and Stages/Ages are associated with it.
Because of how the look-up tables work in Specify, it is sometimes necessary to type 'Upper/Late' and then choose which upper/late you are using. Typing "Cretaceous" in the Chronostrat field will not let you select Upper/Late.
