"Silence mind" is not Zen. If we abide in silence mind, it soon breaks. Trying to stay in this mind of silence can be a source of confusion or disturbance. When we do Zen, the appearance is that we are supposed to be silent. Zen is the mind where both silence and disturbance is cut off. So from the outside it might look like silence but on the inside of someone doing Zen, its not silence either. We have to know this in order to practice correctly.
Because when we do Zen we sit quietly, some imagine we are supposed to be silent inside too. For most people, because they begin their Zen practice with this misunderstanding, they find the practice difficult. But for someone who understands the practice correctly, they don't get caught in silence or disturbance; so they just go directly to their awakened nature. This Zen nature is referred to as "miraculous awareness".