Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Finite strain analysis and vorticity estimation in the metamorphic rocks around Mashhad

Document Type : Original Research Paper

Authors
S. Dashti Chandanagh 1
M. R. Sheikholeslami 2
J. Taheri 3
1 M.Sc. Student, Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran
2 Associate Professor, Research Institute for Earth Sciences, Geological Survey of Iran, Tehran, Iran
3 Ph.D., Geological Survey of Iran, NE Branch, Mashhad, Iran
10.22071/gsj.2018.63826
Abstract
This study was conducted to determine the deformation pattern of the Mashhad metamorphic rocks which results from the convergence between Turan and Central Iran plates and closure of Paleotethys Ocean during Early Cimmerian event. The results of 2D and 3D strain analysis show that the maximum deformation is concentrated in the central part of the study area and most strain shape parameters (K) obtained from oriented samples are located within the flattening part of the Flinn diagram. Strain intensity parameter in most cases is less than 0.5 and a maximum strain occurred in the central part which is reduced towards the margins. This is the most characteristic of the typical shear zones in which, the maximum strain is concentrated on the central part. Calculated vorticity numbers is ranged between 0.2 to 1 indicating the presence of both pure shear and simple shear during a transpressional regional deformation.


Keywords
Binalud
deformation
Strain
Vorticity
References
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Scientific Quarterly Journal of Geosciences
Volume 27, Issue 107
Volume 26, Issue 107, spring 2018
Spring 2018
Pages 215-220