When visualizing the deep reservoir, what is the most significant difference from the common perception of an 'ocean'?

Answer

The term 'ocean' refers to quantity, not the liquid state of the water

The term 'ocean' is a conceptual description of the quantity of water, as the reality at that depth is rigid, hot, dense rock where water molecules are chemically incorporated.

When visualizing the deep reservoir, what is the most significant difference from the common perception of an 'ocean'?
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