Middle Triassic

Middle Triassic Epoch
247.2–237 million years ago
Ages in the Middle Triassic
-247 —
-246 —
-245 —
-244 —
-243 —
-242 —
-241 —
-240 —
-239 —
-238 —
-237 —
Full recovery of woody trees[1]
Coals return[2]
Scleractinian
corals & calcified sponges[3]
Ages of the Middle Triassic.
Axis scale: millions of years ago.

In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between 247.2 Ma and 237 Ma (million years ago). It is preceded by the Early Triassic epoch and followed by the Late Triassic epoch. The Middle Triassic is divided into the Anisian and Ladinian ages or stages.

Formerly the middle series in the Triassic was also known as Muschelkalk. This name is now only used for a specific unit of rock strata with approximately Middle Triassic age, found in western Europe.

Middle Triassic aged Muschelkalk (Schaumkalk) in Baden-Württemberg, Germany

Middle Triassic FaunaEdit

Following the Permian-Triassic extinction event, the most devastating of all mass extinction events, life recovered slowly. In the Middle Triassic, many groups of organisms reached again higher diversity, such as the marine reptiles (e.g. ichthyosaurs, sauropterygians, thallatosaurs), ray-finned fish and many invertebrate groups like molluscs (ammonoids, bivalves, gastropods).

During the Middle Triassic, there were no flowering plants, but instead there were ferns and mosses. Small dinosaurs began to appear, like Nyasasaurus and the ichnogenus Iranosauripus.

ReferencesEdit


  1. ^ McElwain, J. C.; Punyasena, S. W. (2007). "Mass extinction events and the plant fossil record". Trends in Ecology & Evolution. 22 (10): 548–557. doi:10.1016/j.tree.2007.09.003. PMID 17919771.
  2. ^ Retallack, G. J.; Veevers, J.; Morante, R. (1996). "Global coal gap between Permian–Triassic extinctions and middle Triassic recovery of peat forming plants". GSA Bulletin. 108 (2): 195–207. doi:10.1130/0016-7606(1996)108<0195:GCGBPT>2.3.CO;2. Retrieved 2007-09-29.
  3. ^ Payne, J. L.; Lehrmann, D. J.; Wei, J.; Orchard, M. J.; Schrag, D. P.; Knoll, A. H. (2004). "Large Perturbations of the Carbon Cycle During Recovery from the End-Permian Extinction". Science. 305 (5683): 506–9. doi:10.1126/science.1097023. PMID 15273391.