- Norian
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System Series Stage Age (Ma) Jurassic Lower Hettangian younger Triassic Upper Rhaetian 199.6–203.6 Norian 203.6–216.5 Carnian 216.5–228.0 Middle Ladinian 228.0–237.0 Anisian 237.0–245.0 Lower Olenekian 245.0–249.7 Induan 249.7–251.0 Permian Lopingian Changhsingian older Subdivision of the Triassic system according to the IUGS, as of July 2009. The Norian is a division of the Triassic geological period. It has the rank of an age (geochronology) or stage (chronostratigraphy). The Norian lasted from 216.5 ± 2.0 to 203.6 ± 1.5 million years ago.[1] It was preceded by the Carnian and succeeded by the Rhaetian.[2]
Contents
Stratigraphic definitions
The Norian was named after the Noric Alps in Austria. The stage was introduced into scientific literature by Austrian geologist Edmund Mojsisovics von Mojsvar in 1869.
The Norian stage begins at the base of the ammonite biozones of Klamathites macrolobatus and Stikinoceras kerri, and at the base of the conodont biozones of Metapolygnathus communisti and Metapolygnathus primitius. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed.
The top of the Norian (the base of the Rhaetian) is at the first appearance of ammonite species Cochloceras amoenum. The base of the Rheatian is also close to the first appearance of conodont species Misikella spp. and Epigondolella mosheri and the radiolarid species Proparvicingula moniliformis.
In the Tethys domain, the Norian stage contains six ammonite biozones:
- zone of Halorites macer
- zone of Himavatites hogarti
- zone of Cyrtopleurites bicrenatus
- zone of Juvavites magnus
- zone of Malayites paulckei
- zone of Guembelites jandianus
Palaeontology
- Synapsids
- Aetosaurs
- Dicynodonts
- Phytosaurs
Dinosaurs
Dinosaurs of the Norian Taxa Presence Location Description Images Late Carnian to early Norian Ghost Ranch, New Mexico, USA Norian/Rhaetian †Pterosaurs
Pterosaurs of the Norian Taxa Presence Location Description Images Crocodylomorphs
Crocodylomorphs of the Norian Taxa Presence Location Description Images †Ichthyosaurs
Ichthyosaurs of the Norian Taxa Presence Location Description Images - Shonisaurus popularis
†Dinosauromorphs (non-dinosaurian)
†Non-dinosaurian dinosauromorphs of the Norian Taxa Presence Location Description Images New Mexico †Placodonts
Placodonts of the Norian Taxa Presence Location Description Images †Crurotarsans (non-crocodylomorph)
†Non-crocodylomorph Crurotarsans of the Carnian Taxa Presence Location Description Images Mammaliaformes
Mammaliaformes of the Carnian Taxa Presence Location Description Images - Kuehneotherium
From Norian to Sinemurian Greenland and Western Europe A Late Triassic-Early Jurassic symmetrodontan. - Sinocodon
†Ammonites
References
Notes
Literature
- Brack, P.; Rieber, H.; Nicora, A. & Mundil, R.; 2005: The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale, Episodes 28(4), pp. 233-244.
- Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press.
- Martz, J.W.; 2008: Lithostratigraphy, chemostratigraphy, and vertebrate biostratigraphy of the Dockum Group (Upper Triassic), of southern Garza County, West Texas, Doctoral Dissertation, Texas Tech.
External links
- GeoWhen Database - Norian
- Upper Triassic timescale, at the website of the subcommission for stratigraphic information of the ICS
- Norges Network of offshore records of geology and stratigraphy: Stratigraphic charts for the Triassic, [1] and [2]
Triassic Period Lower/Early Triassic Middle Triassic Upper/Late Triassic Induan | Olenekian Anisian | Ladinian Carnian | Norian
RhaetianCategories:
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