Question

Recent development in stratigraphic classification

Answer 1

This article is a presentation of a new initiative of the IUGS International Subcommission on Stratigraphic Classification (ISSC), which was created in 1952 at the 19th International Geological Congress in Algiers. The production of an international stratigraphic guide has been since the beginning a principal objective of the Subcommission. Two International Guides have been published so far (Hedberg 1976 and Salvador 1994), plus an abridged version (Murphy & Salvador 1999).Stratigraphy underwent an unprecedented, extremely rapid development in the last two or three decades resulting from the introduction and application of new techniques, from the multidisciplinary approach, and from the availability of a vast data set (for the post Middle Jurassic time) originated by long term successful scientific programs such as DSDP-ODP-IODP. A revision of the ages published in the existing guides in the light of the new highly specialized and diverse subdisciplines that are currently used for the definition of GSSPs (Global Stratotype Sections and Points) therefore seems timely.Starting from the first Workshop organized by ISSC during the 32nd International Geological Congress held in Florence 2004, a new "bottom up" approach was initiated, with the appointment of several task-groups in order to prepare a series of articles dedicated to the various stratigraphic subdisciplines.The role of the Subcommission chair is that of a scientific coordinator of the series, entitled NEW DEVELOPMENTS IN STRATIGRAPHIC CLASSIFICATION. The articles include examples illustrating the application of the principles to case studies from different parts of the world and from different ages.