Ocean synonyms in Chinese

[redwagon1]

Apart from "sea", there are not a lot of synonyms in English for "ocean". There are some synonyms which might be thought of as poetic, not in common use, such as "the deep" or "main" to refer to the open ocean, as in creatures of "the deep", or sailing over the "rolling main" or "bounding main".  Informally, there is the "pond", as in "across the pond", generally used when one is referring to the other side of the Atlantic Ocean. I think I 've also seen "the blue", but this can be confusing as the sky is also referred to as "the blue".

In Chinese, are there a variety of synonyms for the ocean, the open ocean, the seas, etc., or are synonyms limited as in English?  Do the synonyms have subtle differences in meaning?

Are there poetic terms for the open ocean which are commonly or occasionally used in Chinese?  Can someone offer a sense of the conceptual differences between such words?

Thanks very much.  Bob