"Reconstructing Past Climate Variability in the Central Zagros through X-ray Diffraction (XRD) Analysis"

Subject Areas : watere sciences

Mohammad Javad Nasr Esfahani ^{1 *} , Hassan Torabi podeh ² , Razieh Jafaraghaeie ³ , Roozbeh Aghamajidi ⁴

1 - Khuzestan Water and Power Authority (KWPA)
2 - Faculty of Water Department, Lorestan University
3 - Islamic Azad University, Shushtar Branch
4 - Assistant Prof. Department of Civil Engineering, Sep.C, Islamic Azad University, Sepidan, Iran

Received: 2025-10-03 Published : 2025-11-21

Keywords: Paleoclimatology, stalagmite, stable isotope, Moghare Cave, Central Zagros,

Abstract :

Paleoclimatology is an effective tool for understanding past climatic changes and predicting future conditions. In this research, climate and precipitation variations in the Central Zagros region were investigated using isotopic data from a stalagmite from Moghar Cave (Khorramabad, Lorestan).

The selected stalagmite sample was analyzed using various methods, including stable isotope analysis (δ¹⁸O and δ¹³C), XRD analysis, and U/Th dating. The results indicated an increasing trend in δ¹⁸O values over the last approximately 550,000 years, signifying a shift in the regional climate towards drier conditions and decreased rainfall. The data also revealed alternating wet and dry periods on different timescales, which are consistent with glacial and interglacial cycles. Furthermore, an examination of the water quality and the sample's mineral structure confirmed that the stalagmite formed under isotopic equilibrium conditions.

The findings of this study were compared with other regional and global paleoclimate records and showed significant convergence. In conclusion, by presenting the first speleothem-based data from the Central Zagros, this research represents a significant step in filling a crucial gap in paleoclimatological studies in Iran.

 

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