PALYNOLOGICAL STUDY OF PALEOZOIC SEDIMENTS OF THE CHAL-I-SHEH AREA, SOUTHWESTERN IRAN

Abstract

The Paleozoic sediments of the Chal-i-Sheh area in southwestern Iran comprising
of Mila Formation, Ilebek Formation and Faraghan Formation, were studied
palynologically. The samples containing well-preserved palynomorphs include
acritarchs, chitinozoans, scolecodonts and pollenlspores. A palynological zonation
has been established and comparison was made with other parts of the world. Based
on stratigraphic potential of the diagnostic taxa, the Mila Formation is uppermost
Cambrian to lowermost Tremadocian, Ilebek'Formation Tremadocian and the
Faraghan Formation is Lower Permian. Therefore, there is a hiatus within the
Paleozoic sequence of the Chal-i-Sheh area extending from Upper Ordovician into
the Lower Permian. This hiatus possibly coincides with Hercynian Orogeny which
resulted in the emergence of the Zagros Basin and produced extensive erosion.
Comparing palynomorphs of the Paleozoic sediments of Chal-i-Sheh with published
palynological data, reveals that the Zagros Basin has been part of the "Mediterranean
Acritarch Province" during the Lower Ordovician. The presence of gondwanic
palynomorphs within the Faraghan Formation suggests a gondwanic relationship in
the Permian period.