<abstract xmlns="http://www.w3.org/1999/xhtml">The NW–trending Three Pagodas shear zone exposes a high–grade metamorphic complex named Thabsila gneiss in the Kanchanaburi region, western Thailand. The quartz mylonites within this strike–slip zone were selected for strain analysis. 2–dimensional strain analysis indicates that the averaged strain ratio (Rs) for the lower greenschist facies increment of XZ– plane is Rs = 1.60–1.97 by using the Fry’s method. Kinematic vorticity analysis of the quartz mylonites in the shear zone showed that the mean kinematic vorticity number of this increment is Wk = 0.75–0.99 with an average at 0.90 ±0.07. The results implied that the quartz mylonites within the Three Pagodas shear zone have a dominant simple shear component of about 72% with a small pure shear component. A sinistral shear sense is indicated by kinematic indicators from macro– to micro–scale. We conclude that the Three Pagodas shear zone deformed in the process of sinstral shear–dominated transpression, which is similar to the Mae Ping shear zone in the north.</abstract>

The NW–trending Three Pagodas shear zone exposes a high–grade metamorphic complex named Thabsila gneiss in the Kanchanaburi region, western Thailand. The quartz mylonites within this strike–slip zone were selected for strain analysis. 2–dimensional strain analysis indicates that the averaged strain ratio (Rs) for the lower greenschist facies increment of XZ– plane is Rs = 1.60–1.97 by using the Fry’s method. Kinematic vorticity analysis of the quartz mylonites in the shear zone showed that the mean kinematic vorticity number of this increment is Wk = 0.75–0.99 with an average at 0.90 ±0.07. The results implied that the quartz mylonites within the Three Pagodas shear zone have a dominant simple shear component of about 72% with a small pure shear component. A sinistral shear sense is indicated by kinematic indicators from macro– to micro–scale. We conclude that the Three Pagodas shear zone deformed in the process of sinstral shear–dominated transpression, which is similar to the Mae Ping shear zone in the north.

Quantitative finite strain analysis of the quartz mylonites within the Three Pagodas shear zone, western Thailand

Department of Geology, Faculty of Science

Department of Geodynamics and Sedimentology

Department of Earth Sciences, Faculty of Science

Austrian Journal of Earth Sciences

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The NW–trending Three Pagodas shear zone exposes a high–grade metamorphic complex named Thabsila gneiss in the Kanchanaburi region, western Thailand. The...

Quantitative finite strain analysis of the quartz mylonites within the Three Pagodas shear zone, western Thailand

Published Online: Feb 23, 2019

Page range: 171 - 179

Received: Apr 25, 2018

Accepted: Aug 20, 2018

DOI: https://doi.org/10.17738/ajes.2018.0011

Keywords
Finite strain, Kinematic vorticity, Sinistral, Three Pagodas shear zone, Thailand

© 2018 Pitsanupong Kanjanapayont et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Quantitative finite strain analysis of the quartz mylonites within the Three Pagodas shear zone, western Thailand

Published Online: Feb 23, 2019

Page range: 171 - 179

Received: Apr 25, 2018

Accepted: Aug 20, 2018

DOI: https://doi.org/10.17738/ajes.2018.0011

KeywordsFinite strain, Kinematic vorticity, Sinistral, Three Pagodas shear zone, Thailand

© 2018 Pitsanupong Kanjanapayont et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Finite strain, Kinematic vorticity, Sinistral, Three Pagodas shear zone, Thailand