Conjugate faulting along preexisting fractures in

Authors: Manish K Purohit K K Prajapati R K Trivedi

Publish Date: 2011/08/17

Volume: 76, Issue: 5, Pages: 479-

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Abstract

Reexamination of the outcrop of conjugate of strikeslip faults mapped by Roday et al 1989 near forest rest house at Hirapur reveals that the main dextral strikeslip fault that strikes N35°E and is a manifestation of the earliest NESW trending subhorizontal σ1 that produced extensional reef system in the Bundelkhand massif Although the change in the stress system though 90° rotation of the principal compressive stress σ1 and σ3 with σ2 maintaining near vertically is correct another point of interest is that the σ1 for the system of faults bisects the obtuse angle between the two sets and not an acute one as required by the brittle failure criterion The sinistral strikeslip faults were probably formed by rejuvenation of the initial dextral strikeslip faults that were generated when the maximum principal compressive stress was oriented NS The reversal of fault displacement is seen on all scales in the Bundelkhand massif The dextral strikeslip fault related to the late stress system was preferentially produced along preexisting tensile fractures that were generated under NESW directed subhorizontal σ1 Some of these fractures were converted into sinistral strikeslip faults under NS directed maximum principal compression acting subhorizontally

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