Writers : Rotner,A.
Refference : Geosciences Scientific Quarterly Journal,No.27_28
Publishing Year : 1377

Abstract :

A particular sequence of Triassic rocks is exposed in the erosional window of Aghdarband in the easternmost part ol the Kopet Dagh(Koppeh Dagh) mountains, 100 kilometers east_southeast of the town Mashhad. It bears obvious relation to special sections of the Nakhlak Group(Central Iran), and it shows also some similarities to lowest parts of Triassic )sequences in North-Iran(Alborz Mountains). But on the whole, the Triassic rock sequence in question has an idividuality of its own; it is the result of an intermittent sedimentation in a Triassic "Aghdarband Sea.
In this Triassic rock sequence four formations are distinguishable; these are, from base to top
the Sefid Kuh Limestone Formation the Nazarkadeh Limestone Formation the Sina Volcanic Formation .the Miankuhi Shale Formation
Originally, these four formations were comprised to a Triassic Aghdarband Group(A.RUTNER1991 , 1993).
�According to the suggestion of the National Iranian Stratigraphy Committee, however, the Miankuhi Formation should better not be included in that Group, because of the probable existence of a considerable gap of sedimentation between this Formation and the top of the underlying Sina Formation.But, since such a gap in sedimentation exists very probably also at the base of the Sina Formation, it seems advisable to abandon the term Aghdarband Group' altogether and to deal with each of the four formations individually
The Qara Gheitan Formation below the Sefid Kuh Limestone Formation is more complete exposed al
sites outside the Aghdarband area proper. The Ghaleh Qabri Shales- exposed far to the east of Aghdarband _ await still .closer examination
Sefid Kuh limestone Formation.

Subject List : Triass