The 'parallel feature' line is probably the flotsam and jetsam line that is always somewhere offshore. This is where the coastal currents and the open ocean currents meet, where the green (or brown) water meets the blue as the fishermen say. This is where all of the trash that empties into the ocean, and is thrown or lost overboard meet and mingle with the seaweed and is a bonafide fish magnet.
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"And sometimes is seen a strange spot in the sky A human being that was given to fly"....Eddie Vedder