Personification Definition:
Pretty much give or compare an inanimate thing with human qualities.
Examples that come out in the poem:
"Puts an arm of sand in the span of salt" It compares the sand with an arm.
Hyperbole: An exaggeration.
Examples that come out in the poem:
"The lucid and endless wrinkles" The waves won't be endless, so it's somewhat of an exaggeration.
Metaphor: Similar to a simile, but without like or comparison words. A figure of speech.
Examples from the poem:
The answer to the first one (personification). Compares sand with an arm, without like or similar.
Alliteration: A series of words with the same first letter
Examples from the poem:
"Shadows of Ships" both start with SH. "Low blue Lustre" Both start with L.
Repetition: Reoccuring things.
Ex: In the beginning of the poem, it says Shadows of Ships. Says the same thing in the end. The sense of beginning and finality?
I don't know if this helped. Hope it did :)