Subcommission for Stratigraphic Information (SSI) 
of the
International Commission on Stratigraphy 
of
International Union of Geological Sciences 
Earth’s history is a fascinating topic. The Subcommission for Stratigraphic Information (of International Commission on Stratigraphy of IUGS) strives to provide the global public and geoscience community with quick and free access to a wealth of information about our planet’s past.
On our website, among other items, you will find:
(1) GSSPs – The divisions of geologic time, such as Jurassic or Danian, are defined at a Global Boundary Stratotype Section and Point (GSSP) that marks the international reference for their base. We have compiled summary tables and graphics for all ratified GSSPs and pending candidates.
(2) CHARTS & BOOKS – From the popular page-sized geologic time scale to poster-sized Earth’s history, all in official colors.
(3) STRATIGRAPHIC GUIDE – a concise version of the official manual.
(4) RESOURCES – including diagrams of inter-regional correlations, links to lexicons (national rock formations), “GeoWhen” database of historic and regional stage names, and selected links to other Earth history sites.
(5) TS-CREATOR – our Time Scale Creator visualization package (free JAVA program for all platforms) enables you to explore relationships and make custom charts from a database suite of over 20,000 biologic, geomagnetic, sea-level, and other events. Plus, you can load datapacks ranging from British Isles geology to New Zealand fossil ranges. On-screen displays have extensive hot-links to provide additional information.
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