Application of graphic correlation to compare Lower Permian sections of the Glass Mountains, West Texas and the Western Slope of the Ural Mountains, Russia

Abstract

An Artinskian-Kungirian Global Boundary Stratotype Section and Point (GSSP) has been proposed for two stratigraphic intervals: the Artinskian through Kungurian stages of the western slope of the Ural Mountains, Russia, and the Leonardian Series of the Glass Mountains, West Texas. Graphic correlation applied separately to each of these intervals produced a viable composite section for the Glass Mountains Leonardian succession, whereas a composite section for the Artinskian-Kungurian succession could not be constructed within an acceptable level of confidence. In graphic correlation, selection of a standard reference section (SRS), which acts as the starting point for all succeeding graphic correlations, is an essential first step. Therefore, because the requirements for a global boundary stratotype section are essentially the same as the requirements for a SRS, it is concluded that the Arinskian-Kungirian GSSP should be established in a Leonardian section of the Glass Mountains rather than in a section from the Artinskian-Kungurian interval of the Ural Mountains.