Geochemistry of the Asmari Formation at the Tang-e-Sapou and Tang-e-Ban Outcrop Sections, Kohgiluyeh va Bouyer Ahmad Province

Mossadegh, Z.K.; Adabi, M.H.; Sadeghi, A.

doi:10.22071/gsj.2010.55637

Document Type : Original Research Paper

Authors

Department of Geology, Science Faculty, Shahid Beheshti University, Tehran, Iran

https://doi.org/10.22071/gsj.2010.55637

Abstract

We studied the geochemistry of the Asmari Formation in two outcrop sections: Tang-e-Sapou a 260 m section near Dehdasht City (Kohgiluyeh va Bouyer Ahmad Province) and Tang-e-Ban a 214 m section near Behbahan City (Khozestan Province). Sampling included the complete Asmari Formation and the top of the Pabdeh Formation. The Late Oligocene to Early Miocene Asmari Formation lies above the Pabdeh Formation and is overlain by the Gachsaran Formation. Elemental geochemistry (Fe, Mg, Na, Sr, Mn, Ca), and Oxygen and Carbon isotope analyses indicate that meteoric diagenesis affected carbonates of the Asmari Formation. The δ¹⁸O/δ¹³C data plots in an inverted J-trend suggesting that meteoric diagensis occurred in a closed to semi-closed system. The geochemistry also suggests that the original mineralogy was Aragonite. The boundary between the Pabdeh and Asmari Formations can be recognized by changes in the δ¹⁸O and δ¹³C. In the Pabdeh Formation the δ¹⁸O and δ¹³C values are mostly negative, but in the Asmari Formation values range from positive to negative. Strontium is much higher in the Pabdeh Formation than in the Asmari Formation. Changes in isotope and elemental geochemistry clearly show the Chattian-Aquitanian and Aquitanian-Burgidalian boundaries.

Keywords

20.1001.1.10237429.1389.19.76.4.7

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Scientific Quarterly Journal of Geosciences

Geochemistry of the Asmari Formation at the Tang-e-Sapou and Tang-e-Ban Outcrop Sections, Kohgiluyeh va Bouyer Ahmad Province

References

References

Volume 19, Issue 76
January 2010
Pages 23-32

Geochemistry of the Asmari Formation at the Tang-e-Sapou and Tang-e-Ban Outcrop Sections, Kohgiluyeh va Bouyer Ahmad Province

References

References

Volume 19, Issue 76January 2010Pages 23-32

Volume 19, Issue 76
January 2010
Pages 23-32