Strain Analysis in Rock Group of Pur-Basin, India


  • A. P. Chowdhury Sidhu Kanu Birsha University, Purulia, India
  • L. P. Bosevska Ukrainian Salt Research Institute, Bakhmut
Keywords: strain analysis, Isogon Rosette method, FRY analysis, Pur-Banera Belt, Aravalli craton

Abstract

Precambrian rocks exposed around Pur are a part of Pur-Banera belt that is stratigraphically placed within Aravalli Quartzite, Calc Silicate Gneiss, Quartzite and Garnetiferous Mica Supergroup. The different lithological units exposed in the area are Banded Magnetite Schist. These rocks have been subjected to multi-deformational episodes. In accordance with the modern system of multi-level deformation analysis proposed by Fedor Yakovlev in 2012, the results of the The work belongs to the scientific direction of tectonophysics, which was called “strain analysis of linear folding structures”. The present study involves analysis of strain in the rocks around Pur, Bhilwara District, Rajasthan (India). The deformation analysis at the level of folds (level three of seven) are presented in this work. The outcrop pattern is an isoclinal fold of D2 generation, whose axis plunges steeply NE’ly with an axial plane trending NNE-SSW. The quartzite band in this Pur Synform was sampled for the purpose of strain analysis. This section parallel to the YZ plane of finite strain ellipsoid was prepared (perpendicular to both Schistosity and the lineation). The accepted methods used to estimate strain are a) Fry method and b) “Isogon Rosette” method. The axial ratio of the strain ellipse and the orientation of the long axis of the strain ellipse were computed for every location. It was seen that the strain ratio is nearly uniform in magnitude. The orientation of the long axis of the strain ellipse (Y direction of the finite strain ellipsoid) is also constant in space and parallel to the axial trace of D2 Synform. From the analysis it was suggested a strong flattening following the buckling. The amount of this flattening strain was computed using the”Isogon rosette” method. We calculated reflects the flattening strain recorded in the rock with the very high constancy of the strain ratio and the orientation of the long axis of the strain ellipse irrespective of the methodology adopted. The results of performed researches bring tectonophysics database up-to-date providing an excellent opportunity for provenance analysis of the Pur-basin using the different types of undulose extinction of the quartzite for development of prospective mining projects around the area including iron deposits.

Author Biographies

A. P. Chowdhury, Sidhu Kanu Birsha University, Purulia, India
Sidhu Kanu Birsha University, Purulia, India
L. P. Bosevska, Ukrainian Salt Research Institute, Bakhmut
Ukrainian Salt Research Institute, BakhmutPhD, Leading Researcher 

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Published
2017-12-19
How to Cite
Chowdhury, A., & Bosevska, L. (2017). Strain Analysis in Rock Group of Pur-Basin, India. Journal of Geology, Geography and Geoecology, 25(2), 23-37. https://doi.org/https://doi.org/10.15421/111717