The Fate of Formal Lithostratigraphy

Abstract

Hollis D. Hedberg, the first chairman of the International Subcommission on Stratigraphic Classification (ISSC), compiled and published the International Stratigraphic Guide (ISG) in 1976 after a long and successful endeavour. The guide contains definitions, procedures, terminology, and nomenclature, with detailed information on three stratigraphic categories, including that of lithostratigraphy. In the definition of a lithostratigraphic unit, it was stated that “a lithostratigraphic unit may consist of sedimentary, or igneous, or metamorphic rocks, or an association of two or more of these.” Salvador (1994) suggested an alternative definition of lithostratigraphic terminology under the F4 subheading. It more obviously occurs in the North American and the Australian stratigraphic codes. The result is that national guides or codes and practice vary, and the correlation of lithostratigraphic units is unsolved, which is also expressed in geological maps. It is high time that the reconsideration of lithostratigraphic terminology was put on the agenda of the ISSC.