The Chill 2: Metaphor and motifs
There are a couple of motifs that recur throughout the book.
One is the fog that surrounds Pacific Point at the start of the book. Does the fog represent Archer's inability to understand the situation with Dolly, Helen, and so on? What do you make of the occasion when Archer moves above the fog when he drives to Indian Springs to talk to Alice Jenks? Is that the point where things become clearer, either to Archer or the reader?
Another motif is the number of references to philosophy, especially Zeno's paradox. (Other Lew Archer books don't feature this motif.) Does this help the reader get a sense of Archer's perceived lack of progress? Does it help reinforce the academic/college setting of much of the book?
(There are a few nautical references in the book, but I'm not sure what to make of them in terms of helping the theme.)