Abstract: The formulation of a geological code refers to the summarization of regularities and theories through repeated iovestigations of a geological phenomenon or event in a typical geological area for a special subject and collection of sufficient evidence in order to provide an example or guide for geological work and criteria or a yardstick for geological correlation. The pager proposes the envisaged framework for the work of formulation of geological codes in the 1990’s, including that of guide nature, that on a regional scale or in a typical geological area, that of a discipline or speciality and that of a special subject.