There are two scenarios for the mechanisms and mechanics of multiple shear bands.

First, formation of multiple sets of shear bands under the same stress regime. Please see the 'Conjugate Faults' and 'Four Sets of Shear Band Faults.' The latter was thought to be in order to accommodate three dimensional strains (Aydin and Reches, 1982).

The latter sets may also form at different times in response to a variation of the driving stresses.