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Recent discoveries of dynamic ice Ⅶ and superionic ice highlight the importance of ionic diffusions in discriminating high-pressure (P) water phases.The rare event nature and the chemical bond breaking associated with these diffusions,however,make extensive simulations of these processes unpractical to ab initio and inappropriate for force field based methods.Using a first-principles neural network potential,we performed a theoretical study of water at 5 70 GPa and 300 3000K.Long-time dynamics of protons and oxygens were found indispensable in discriminating several subtle states of water,characterized by protons and oxygen ions diffusion coefficients and the distribution of protons displacements.Within dynamic ice Ⅶ,two types of proton transfer mechanisms,i.e.,translational and rotational transfers,were identified to discriminate this region further into dynamic ice Ⅶ T and dynamic ice Ⅶ R.The triple point between ice Ⅶ,superionic ice (SI),and liquid exists because the loosening of the bcc oxygen skeleton is prevented by the decrease of interatomic distances at high Ps.The melting of ice Ⅶ above ～40 GPa can be understood as a process of two individual steps: the melting of protons and the retarded melting of oxygens,responsible for the forming of SI.The boundary of the dynamic ice Ⅶ and SI lies on the continuation line ice Ⅶs melting curve at low Ps.Based on these,a detailed phase diagram is given,which may shed light on studies of water under Ps in a wide range of interdisciplinary sciences.