NORTH AMERICAN COMMISSION ON STRATIGRAPHIC NOMENCLATURE Note 68 - Application for Addition of Submembers to the North American Stratigraphic Code: A Case for Formalizing Lithostratigraphic units of Intermediate Rank
|Title||NORTH AMERICAN COMMISSION ON STRATIGRAPHIC NOMENCLATURE Note 68 - Application for Addition of Submembers to the North American Stratigraphic Code: A Case for Formalizing Lithostratigraphic units of Intermediate Rank|
|Publication Type||Journal Article|
|Year of Publication||2018|
|Authors||Brett, CE, Pratt, BR, Landing, E|
|Pagination||103 - 108|
The existing hierarchy of formal lithostratigraphic units of the North American Stratigraphic Code (NACSN 2005) recognizes “Bed” or “Beds” (Flow in the case of volcanic rocks) as the only formal subdivision of members. Beds, in a geological context, are discrete depositional/accumulation units bounded by bedding planes and the formal term Bed should not be applied to thicker subdivisions of members composed of several discrete and distinguishable beds, especially of differing lithology. In such cases, thicker divisions of members that may contain one or more formally named Beds, would be usefully assigned to the division termed “Submember”. In this paper we review the issue, discuss the justification of formalizing submembers, and propose a formal amendment to the North American Stratigraphic Code.