  The vortex lattice in a Type II superconductor provides a versatile model
system to investigate the order-disorder transition in a periodic medium in the
presence of random pinning. Here, using scanning tunnelling spectroscopy in a
weakly pinned Co0.0075NbSe2 single crystal, we show that at low temperatures,
the vortex lattice in a 3-dimensional superconductor disorders in two steps
across the peak effect. At the onset of the peak effect, the equilibrium Bragg
glass transforms into an orientational glass through the proliferation of
dislocations. At a higher field, the dislocations dissociate into isolated
disclination giving rise to an amorphous vortex glass. We also show the
existence of a variety of additional non-equilibrium metastable states, which
can be accessed through different thermomagnetic cycling.
