Middle Triassic

Middle Triassic
247.2 – ~237 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Middle Triassic aged Muschelkalk (Schaumkalk) in Baden-Württemberg, Germany
Chronology
−255 — – −250 — – −245 — – −240 — – −235 — – −230 — – −225 — – −220 — – −215 — – −210 — – −205 — – −200 — Pz Mesozoic P Triassic J Lopingian Ear Middle Late Early J Olenekian Induan Anisian Ladinian Carnian Norian Rhaetian         ← Permian-Triassic extinction event ← Smithian–Spathian boundary event[1] ← Carnian pluvial episode ← Full recovery of woody trees[2] ← Coals return[3] ← Scleractinian corals & calcified sponges[4] ← Triassic–Jurassic extinction event ← Manicouagan impact Subdivision of the Triassic according to the ICS, as of 2021.[5] Vertical axis scale: millions of years ago.
Etymology
Name formality	Formal
Usage information
Celestial body	Earth
Regional usage	Global (ICS)
Time scale(s) used	ICS Time Scale
Definition
Chronological unit	Epoch
Stratigraphic unit	Series
Time span formality	Formal
Lower boundary definition	Not formally defined
Lower boundary definition candidates	FAD of the Conodont Chiosella timorensis Base of magnetic zone MT1n
Lower boundary GSSP candidate section(s)	Desli Caira, Northern Dobruja, Romania Guandao, Guizhou, China
Upper boundary definition	FAD of the Ammonite Daxatina canadensis
Upper boundary GSSP	Prati di Stuores, Dolomites, Italy 46°31′37″N 11°55′49″E / 46.5269°N 11.9303°E / 46.5269; 11.9303
Upper GSSP ratified	2008[6]

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.^{[citation needed]}

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.^{[citation needed]}

Middle Triassic life

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

During the Middle Triassic, there were no flowering plants, but instead there were ferns and mosses. Small dinosauriforms began to appear, like Nyasasaurus and the ichnogenus Iranosauripus.^{[citation needed]}

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  Mixosaurus cornalianus restoration, a Middle Triassic ichthyosaur

References

• GeoWhen Database - Middle Triassic

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This page was last edited on 25 February 2024, at 13:35