Abstract

The Upper Triassic Dockum Group of west Texas and eastern New Mexico is a well-established stratigraphic unit with a long history of use extending back more than a century. Recently, major changes in the stratigraphic nomenclature of the Dockum Group have been proposed. Revisionists propose to elevate the Chinle Formation of the Colorado Plateau to group status, subordinate the Dockum as a formation within the Chinle “Group,” and restrict use of the name Dockum “Formation” only to west Texas. In addition, a variety of new names have been proposed for subdivisions of the Dockum Group, and different names are advocated for the same units on either side of the Texas/New Mexico border. These revisions are unjustified and unnecessary, and if adopted would result in confusion by displacing well-known names and requiring use of different names for the same strata in different areas. These changes should not be accepted. An alternative, more traditional nomenclature for the Dockum Group is preferable.