Iranian Journal of Geophysics

Iranian Journal of Geophysics

Three-dimensional rayleigh wave tomography of the Gavarzin salt dome, Qeshm island: structural insights from aftershocks of the 2005 M 6.0 Qeshm earthquake

Document Type : Research Article

Authors
Razieh Heydari Moharloi 1
Abbas Gholamzadeh 2
Mohsen Farrokhi 3
Sara Abbasi 4
1 M.Sc., University of Hormozgan, Bandar Abbas, Iran
2 Associate Professor, University of Hormozgan, Bandar Abbas, Iran
3 Assistant Professor, University of Hormozgan, Bandar Abbas, Iran
4 Ph.D. Iran University of Hormozgan, Bandar Abbas, Iran
10.30499/ijg.2025.511100.1681
Abstract
This study utilizes three-dimensional Rayleigh wave group velocity tomography to investigate the shallow crustal velocity structure of Qeshm Island, located at the eastern end of the Zagros Mountain Range beneath the Bandar Abbas region. Qeshm Island, with its unique geological features, hosts a prominent salt dome known as Gavrzin, recognized as a hydrocarbon trap critical for underground oil and gas storage. Thus, this research emphasizes the necessity of comprehensive investigations into such geological structures due to their economic and environmental implications. For the three-dimensional Rayleigh wave tomography and velocity structure imaging, the study employs the Neighborhood Algorithm, a direct search technique that has emerged in recent decades for geophysical data inversion. The data used include aftershocks from the December 27, 2005 (6 Azar 1384), Qeshm Island earthquake, recorded by a network of 17 short-period seismic stations. The results reveal a salt dome situated near the Qeshm Fault, migrating westward. The initial depth of this salt dome is approximately 15 km, with its dimensions increasing as the depth decreases. The findings indicate that the Qeshm Fault plays a significant role in the formation and displacement of the Gavarzin salt dome. These results enhance the understanding of subsurface geology in the region and carry implications for the exploration and management of subsurface resources.
 
Keywords
Rayleigh waves, neighborhood algorithm, 3D tomography, Qeshm island, Zagros

Subjects

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Iranian Journal of Geophysics
Volume 20, Issue 1
March and April 2026
Pages 33-51