Riim-Ci dependent oblateness of deformed pebbles in the Baraitha conglomerate, Central India and tectonic implications

  • Prakash P. Roday
  • Gopal Maheshwari
  • Narendra H. Vaghmarey


Strain analysis of the Baraitha conglomerate is attempted by direct measurements on extracted pebbles and by micrometric analysis. The overall deformation is of flattening type, with thek value lower by more than half in the matrix than in the pebbles. The viscosity contrast between pebbles and matrix (μ im) is in the ratio of 2:1 and the bulk deformation appears to be strongly controlled by Ci (concentration of pebbles expressed as percentage). The total shortening (≃35%) in the Baraitha conglomerate is comparable with the shortening accomplished in the folding of the overlying Bijawar Group volcanosedimentary sequence. The bulk strain axesX t, Yt andZ t, as determined from the analysis of the deformed conglomerate, are unsymmetrically oriented with reference to folds formed by oblique flexural-slip with neitherX t norY tcoincident with the fold hinges. The lack of transection of folds by cleavage again suggests flattening deformation. The extension in theY tdirection is greater in the matrix than in the pebbles.


Oblateness viscosity contrast pebble concentration tectonic strain ratio initial axial ratio 


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Copyright information

© Indian Academy of Sciences 1990

Authors and Affiliations

  • Prakash P. Roday
    • 1
  • Gopal Maheshwari
    • 1
  • Narendra H. Vaghmarey
    • 1
  1. 1.Department of Applied GeologyUniversity of SagarSagarIndia

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