Permian tetrapod ichnofacies
Three fundamental terms in ichnology are:
assemblage, which is equivalent to an assemblage of body fossils;
ichnocoenosis, which is a trace fossil assemblage produced by a biological community that can be characterized by morphological criteria;
ichnofacies, which refers to recurrent ichnocoenoses that represent a significant portion of Phanerozoic time.
There are five archetypal vertebrate ichnofacies for non-marine environments (Chelichnus, Grallator, Carichnium, Batrachichnus, Characichichnos) of which four are present in the Permian:
Chelichnus ichnofacies — Chelichnus ichnocoenosis;
Batrachichnus ichnofacies — Batrachichnus ichnocoenosis;
Brontopodus ichnofacies — Pachypes ichnocoenosis;
Characichichnos ichnofacies — Serpentichnus ichnocoenosis. The Chelichnus and Characichichnos ichnofacies occur throughout the Permian, the Batrachichnus ichnofacies is restricted to the Early Permian and the Brontopodus to the Middle to Late Permian. The Batrachichnus ichnocoenosis can be divided into the Ichniotherium sub-ichnocoenosis, Amphisauropus sub-ichnocoenosis and the Dimetropus subichnocoenosis, which represent a spectrum of non-marine environments from alluvial fan to tidal flat.
Figures & Tables
Non-Marine Permian Biostratigraphy and Biochronology
During the Permian, the single supercontinent Pangaea stretched from pole to pole. Early Permian glacial deposits are found in southern Gondwana. Along the sutures of Pangaea, mountain ranges towered over vast tropical lowlands. Interior areas included dry deserts where dune sands accumulated. Gypsum and halite beds document the evaporation of hot, shallow seas that formed the most extensive salt deposits in the geological record. The Permian period (251 to 299 Ma) encompasses nine ages (stages) arranged into three epochs (series). Most of the Permian marine timescale has been defined by global stratotype sections and points for the stage boundaries. This volume presents new data regarding the biostratigraphy and biochronology of the non-marine Permian and provides a basis for temporally ordering Permian geological and biotic history on land, and correlating that history to events in the marine realm.