Lithostratigraphy and Biostratigraphyo of Ilam Formation in North Flank of Pusht-e-jangal Anticline in lorestan

Document Type : Research Paper

Authors

Abstract

This study  have aimed to recognize  the planktonic foraminifera and their  morphotype in Ilam formation and categorize them according to their living depth .The sea level changes in basin and time of depositon of ilam foemation has been suggested and also compared with its global changes. According to  the microfacies  the homocline ramp has been suggested  for ilam formation. The planktonic foraminifera of Ilam Formation at this section led to recognition of the 16 genera and 25 species of pelagic foraminifera and oligosteginid، and three biozones as below :
 
1) Dicarinella asymetrica Total Rang Zone
2) Globotruncanita elevate Partial Rang Zone
3) Globotruncana ventricosa Interval Zone
 
According to this  study, the suggested age for Ilam Formation in this section is Late Santonian – Early Campanian.

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