Induan Stage

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Induan Stage

 

the bottom stage of the Lower Triassic. It was identified by L. D. Kiparisova and Iu. N. Popov (USSR) in 1956. In a typical cross section [the Ind River in the Solianoi (Salt) Range] it is composed of sandstone on the bottom and limestone and marl on top. The Induan stage is divided into two zones: Otoceras and Gyronites. Deposits of the Induan stage are extensively developed in Eurasia and also in North America, Africa, and Australia. The term is used primarily by Soviet geologists.

References in periodicals archive ?
Earliest Triassic (Induan) spores and pollen from the Junggar Basin, Xinjiang, northwestern China.
Type genus: Chauliodites Heer, 1864 with 11 species from the Severodvinian--Olenekian of Russia, Induan of Mongolia, Olenekian of Germany, Anisian of France and Middle Triassic of China (Aristov, 2003, 2004b, 2008).
Genera included: Type genus, Triadosialis Handlirsch, 1906 with one species from the Olenekian of Germany; Nivopteria Lin, 1978 with one species from the Middle Triassic of China; Paratomia Aristov, 2004 with one species from the Induan of Russia; Protomia Aristov, 2004 with one species from the Kazanian of Russia; Miralioma Aristov, 2004 with two species from the Kazanian and Urzhumian of Russia; and monotypic Iphikozulu gen.
crofti is probably not the direct forerunner of Neospathodus, which begins only in the Gandarian substage (= Dienerian) of the Brahmanian stage (= Induan stage, the original Induan comprises also the lower substage of the Olenekian) (Kozur 1992e).
The most interesting, because the most disturbing, of her reflections upon her position as woman, as someone from the more highly privileged West and as professional anthropologist, also comes in the form of a story: the story of Induan Amar's baby.
On the basis of present and previous biostratigraphic work the assigned stages are; Induan and Olenekion to Mianwali Formation corresponds two second order composite sequences with time span of 5.1 Ma.
Such younger position, however, has never been demonstrated, and all recent papers report a Claraia range in the western Tethys (Dolomites and Hungary) restricted to the Induan Mazzin and middle Siusi members of the Werfen Formation (Broglio Loriga et al, 1983, 1986, 1990; Neri, 2007) and lower-middle Aracs Marl and Alcsutdoboz formations of the Transdanubia (Hungary) (Kozur, 1987; Broglio Loriga et al., 1990).
Consequently, according to this age assessment, in Spain (Castilian Branch and Minorca), SE France (Provence), Sardinia (Nurra) and Bulgaria (NW Prebalkan and Kraishte), where the presence of ventifacts and their potential value as indicators of an arid period has been emphasized by Durand (2006), this author maintains that, in our current state of knowledge, this dry climatic regime generally started from the late Induan to early Olenekian.
The name of Scythian was accepted as synonymous with the Lower Triassic and was divided into two stages: the Induan, whose name was derived from the Indus river in the Himalaya, and Olenekian from the Olenek river in the south of Siberia.
In contrast, the main marine transgression, even if based on some fossils (Claraia) occurring towards the east of the Adige Valley (Trento-Bolzano), in the Siusi Member of the Werfen Formation, probably developed between Induan and early Olenekian times.
At the beginning of the Early Triassic (Induan), the sedimentation area was restricted to the central part of the Germanic Basin: the Lower Buntsandstein formations, which characterize a playa system, do not have any equivalents on the western margin of the basin (Geluk, 2005).