New Findings in 
Applied Geology

New Findings in Applied Geology

Biostratigraphy the Surgah Formation in the Khorramabad anticline (High Zagros zone)

Authors
1 Assoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, Iran
2 Ph. D. (graduated), Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, Iran
3 M. Sc. (graduated), Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, Iran
4 Ph. D. (graduated), Expert of the Central Laboratory of Lorestan University, Khorramabad, Iran
Abstract
The Surgah Formation is a deep marine sedimentary sequence that extends only in the Lorestan zone and its margins. In order to study the stratigraphic and biostratigraphic characterises of this formation, the Falakolddin section in the High Zagros zone, adjacent to the northern part of the Lorestan zone, was selected. The thickness of the Surgah formation in this section is 80.80 meters and includes dark gray medium to thick argillaceous limestones and limestones, which has more clay content compared to other outcrops of the Surgah Formation. In the biostratigraphic studies of this formation, 18 species of 7 genera of planktonic foraminifera were identified, based on their distribution, four biological zones were introduced, which are: Helvetoglobotruncana helvetica total renge zone, Marginotruncanasigali-Dicarinella primitiva partial range zone, Dicarinella concavata interval zone and Dicarinella asymetrica total range zone. Based on the introduced biozones, the age of Surgah Formation in this section has been determined Middle Turonian-Late Santonian.
Keywords

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Volume 19, Issue 38 - Serial Number 38
December 2025
Pages 132-142

  • Receive Date 12 April 2024
  • Accept Date 12 October 2024