Depreciation of revalued assets

Can some in this forum to impact of debiting the revaluation reserve and crediting the retained earnings of the same amount ? Because this definitely as I know will bring this amount to zero if there is other amount.
Also, why does this not go to the other comprehensive income as a revaluation loss since ? If this impact on the retained earnings . Because the depreciation expense is as a result of surplus depreciation .

I will really be happy if some one can throw more light on this topics before it’s really disturbing .