PermTriasGrenzprofil

PermTriasGrenzprofil is a geological term used to describe the boundary profile at the Permian–Triassic boundary, the transition between the Permian and Triassic periods. The concept encompasses the integrated stratigraphic signal observed in outcrops and drill cores, including lithology, fossil content, and geochemical markers, which together help to correlate sections across regions.

A typical PermTriasGrenzprofil combines multiple lines of evidence. Lithologically, it often shows a noticeable shift in sedimentation and rock type across the boundary. Fossil records reveal a pronounced turnover, with extinction events affecting marine and terrestrial faunas. Geochemically, a negative carbon isotope excursion is frequently recorded, sometimes accompanied by anomalies in trace elements and, in certain localities, ash layers or fungal spikes that point to rapid environmental stress.

Significance and use. The profile is central to understanding the Permian–Triassic mass extinction, the largest biotic crisis in Earth’s history, and to correlating sections worldwide. By comparing PermTriasGrenzprofil sections from different continents, researchers can reconstruct the scale and tempo of environmental change and assess competing theories about the boundary’s cause, such as volcanic activity, climate change, or ocean anoxia.

Geographical distribution and standardization. Well-studied examples exist in records from places like Meishan in China and Karoo Basin in South Africa, among others. The boundary is commonly defined in formal stratigraphy by conodont and fossil markers, with the Meishan section serving as a reference point for global correlation.

See also: Permian–Triassic extinction event, GSSP, Hindeodus parvus, Meishan.