By Tony Briscoe, Chicago Tribune (TNS) CHICAGO — Near the deepest spot in Lake Michigan, the crew aboard the research vessel Blue Heron lowers a device outfitted with a cluster of 8-liter bottles into the dark blue waters until it disappears from sight. After a 10-minute descent, the metal-framed contraption known as a rosette finally lands on the muddy bottom roughly 860 feet below the surface. Between