  We have devised an original laboratory experiment where we investigate the
frictional behaviour of a single crystal salt slider over a large number of
deformation cycles. Because of its physical properties, salt, a surrogate for
natural faults, allows for friction and plastic deformation and pressure
solution creep to be efficient on the same timescale. During the same
experiment, we observe a continuous change of the frictional behaviour of the
slider under constant conditions of stiffness, temperature and loading
velocity. The stick-slip regime is progressively vanishing, eventually reaching
the stable sliding regime. Concomitantly, the contact interface, observed under
the microscope, develops a striated morphology with contact asperities increase
in length and width, arguing for an increase in the critical slip distance dc.
Complementary experiments including velocity jumps show that the frictional
parameters of the rate and state friction law, a and b, progressively vanish
with the cumulative slip. In our experimental conditions, the ultimate stage of
friction is therefore rate and state independent.
