An insight into the formation of Givi agates located in Ardabil province based on stable isotope and fluid inclusion findings

Document Type : Research

Author

Department of geology, Faculty of science, University of Mohaghegh Ardabili, Ardabil, Iran

10.22128/ijcm.2026.3179.1022

Abstract

The study area is located on the Western Alborz-Azerbaijan zone in Ardabil province. The agates in this area occur as massive and sometimes geode within the cavities and voids of the andesitic volcanic host rock. Based on isotopic data, the temperature of agate formation has been obtained as 51.7 to 63.9. The results obtained from the direct δD analysis of the primary fluid inclusins in quartz crystals and the calculated oxygen isotope values indicate that meteoric waters are the main fluids for mineralization. It is thought that meteoric waters in the area have been heated by penetrating into young volcanic units and converted to the hydrothermal fluids and caused argillic alteration in volcanic rocks, releasing silicic components from altered minerals. These fluids, by circulating in the cavities and fractures of volcanic rocks and depositing silica and other components, have caused the formation of agate and other minerals in them.

Keywords


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