CHRONOSTRATIGRAPHIC UNITS NAMED FROM BELGIUM AND ADJACENT AREAS - Preface

Preliminary reports on the concepts and uses of lithostratigraphic, biostratigraphic and chronostratigraphic units were delivered at the International Geological Congress of Montreal, Canada, 1970. They were subsequently formalised as International Stratigraphic Guides (Hedberg, 1976; Salvador, 1994). The recommendations of the International Commission on Stratigraphy (ICS, see: http://www.stratigraphy.org/) of the International Union of Geological Sciences (IUGS, see: http://www.iugs.org/) have generally been well accepted by the Belgian community of geologists as represented by national stratigraphic subcommissions set up under the Belgian National Committee of Geological Sciences. However, the application of these recommendations has taken some time and the need has been felt for documents to synthesise the current situation regarding stratigraphic units named from Belgium and adjacent areas.In 2001, thanks to the collaboration of 44 geologists, a guide to a revised lithostratigraphic scale of Belgium was published in Geologica Belgica (Bultynck & Dejonghe, 2001).A similar volume dealing with the chronostratigraphic units was thought to be necessary to summarise the current scientific knowledge regarding series, stages and substages named from Belgium and adjacent areas. This is particularly relevant at the present time because the status of a number of stages and other units, some of worldwide application, has been changed as a result of recent decisions of the Internatio