DEVELOPING THE INTERNATIONAL GEOLOGIC TIME SCALE - THE NEXT STEP

Efforts to develop a standard, international geologic time scale have been underway for over 25 years by the International Commission of Stratigraphy (ICS), which has been charged by the IUGS to complete the task of defining all stage and system boundaries by 2008. It is now time to increase discussion of what the "completed" geologic time scale will be used for, and therefore, what is necessary to make it an even more useful tool. In essence, we are talking about a community-based system for the continued refinement of the geologic time scale One critical need is to develop a platform or system to help link detailed data for existing or proposed stratotype, reference, and other key stratigraphic sections and all the data associated with them. It is envisioned that this will be a web-based system of linked databases. Each measured section should be "calibrated" with precise and detailed data on lithostratigraphy, biostratigraphy, taxonomy, stratigraphic range, litho- and biofacies, chrono-, sequence, chemo-, magneto- and cyclo-stratigraphy, and geochronology. One major goal is the development of a highly resolved time scale in terms of radiometric ages. Since many stratotype sections do not encompass a long stratigraphic range, it will be key to correlate these to longer reference sections and both marine and terrestrial data are equally important. Key to all of this will be data reproducibility, data attribution (metadata), detailed, precise, and accurate measured sections, and well located samples (bed numbers are insufficient). Finally, so the community can assess these data, access to all of the data must be universal and easy. Tools for correlation and assessment must be provided. Once built, such a system will provide significant impetus for future research on a variety of issues such as: extinction and radiation processes, global correlation, paleogeography, paleoclimatology, space-time pattern of the assembly and break-up of the supercontinents, and numerous other issues of regional and global interest.