Investigation and Comparison of Fabrics and deformation temperature in the Alvand and Boroujerd Granites, Sanandaj–Sirjan Zone

Izadi Kian, Leili; Jafari, Seyedeh Razieh; Piri, Nasrin; Rabbani, Shima

doi:10.22071/gsj.2026.550643.2226

Investigation and Comparison of Fabrics and deformation temperature in the Alvand and Boroujerd Granites, Sanandaj–Sirjan Zone

Articles in Press

Document Type : Original Research Paper

Authors

Leili Izadi kian

Seyedeh Razieh Jafari ¹

nasrin Piri ²

Shima Rabbani ³

¹ Assistant Professor, Assistant Professor, Department of Geology, Faculty of Sciences, Payam Noor University, Tehran, Iran

² Bu-Ali Sinauniversity

³ Bu-Ali Sina university

10.22071/gsj.2026.550643.2226

Abstract

The Alvand and Boroujerd intrusive bodies are among the largest coeval plutons in the northwestern part of the Sanandaj–Sirjan Zone. Both bodies preserve magmatic, transitional, and solid-state fabrics, though with notable differences. In the Alvand granite, magmatic fabrics are generally well preserved across most parts, whereas in the Boroujerd granite, they are largely obliterated by overprinting solid-state fabrics. Moreover, mylonitization is much more pronounced in the Boroujerd granite than in the Alvand granite, indicating stronger overprinting by subsequent deformation. Transitional fabrics in both bodies are expressed by the occurrence of late-stage minerals within fractured domains. In the Alvand granite, although both magmatic and transitional fabrics are well preserved, mylonitization is not pervasive throughout the entire pluton, suggesting that this pluton was not uniformly affected by later deformation. Field and microstructural evidence further indicate that the Alvand pluton formed within an open, dynamic, and multiphase magmatic system. In contrast, the Boroujerd pluton exhibits features of a relatively closed system, where crystallization occurred under comparatively calm conditions without significant magma flow perturbations, and deformation was mostly restricted to the solid state after complete cooling.

Keywords

Alvand

Boroujerd

Fabric

Magma

Tectonics

Sanandaj–Sirjan

Subjects