Kinematic Framework of Heterogeneous Deformation Within Pratapnagar Thrust Sheet, Bhagirathi Valley, in Lesser Garhwal Himalaya. U.P.

The Pratapnagar quartzite constituting Pratapnagar thrust sheet was subjected to strain analysis Assuming the foliation (S₁) in the quartzite as XY plane for strain estimation. sections parallel to XY, XZ and YZ of the quartzite exposed at the base of the Pratapnagar thrust sheet and away from It were prepared The specimens of the quartzite belong to the proximity of the Pratapnagar thrust sheet and witnessed increasing trend of flattening as indicated by two dimensional strain ratio (R_s) The three dimensional finite strain Was higher in intensity (E_s = 0676 to 0937) and is marked by oblate type of ellipsoid (k).

In contrast to this, the quartzite located away from the thrust was subjected to progressive plane and constrictional type of strain and the shape of the ellipsoid Was prolate This indicates that away from the thrust the strain was variable but it acquired unidirectional trend with greater amount of intensity giving rise to extreme flattening parallel to Z. The stretching of the quartz grams was maximum along X, more or less, comciding with the NESW trending thrust transport direction.