Half a mile below the surface of the ocean, off the coast of Oregon, the Alvin submersible's headlights flicker on to reveal a colorful oasis. Plush carpets of white, yellow and orange microbes cover the seafloor, punctuated by fields of clams and mussels. Red rockfish watch the vessel warily with bulbous milky eyes, while bubble plumes belch from mounds of chalky, variegated rock. The halo of illumination draws visitors forward like a lure, exposing this alien terrain bit by unexpected bit while obscuring its true extent.