Publications

Yazdanbakhsh, S; Koochakzaei, A; Achachluei, MM (2025). Sclerochronology of Callista Umbonella to extract the transfer function for reconstructing climates in some parts of Persian Gulf. GEO-MARINE LETTERS, 45(2), 15.

Abstract
This paper aims to assess the feasibility of using the shell of Callista umbonella for sclerochronology and sclerochemistry studies, with the goal of reconstructing the climatic conditions of the northern Persian Gulf, specifically the north of the Strait of Hormuz. One hundred bivalves of C. umbonella were collected from Bostanu in June 2020, and their shells were processed by removing organic matter, mounting, and preparing transverse sections. Ten shell samples were chosen for sclerochronology evaluation. Tidal data with 30-min accuracy were obtained from the hydrographic management database of the National Cartography Center of Iran, while sea surface temperature (SST) data in the studied area were extracted from Moderate Resolution Imaging Spectroradiometer (MODIS) data on board the Aqua satellite. For each month of mollusc life, one sample from a shell was taken, and the isotope ratio was analyzed using an isotope ratio mass spectrometer (IRMS). A total of 13 samples were analyzed. The results showed that the life of the sample was 572 days, and the growth bands evaluated were in good agreement with the tidal data. The growth rate showed a strong correlation with SST changes. By establishing a relationship between the aragonite equilibrium fractionation factor, the average monthly SST, and the results of sclerochemistry and IRMS analysis, the delta O-18(water) value was removed from the previous function. Finally, the transfer function was developed to reconstruct weather conditions based on the relationship between SST in Celsius and delta O-18(shell) value with regard to shell formation and environmental conditions during the time and place of biomineralization of the organism.

DOI:
10.1007/s00367-025-00803-x

ISSN:
1432-1157