Experience the breathtaking detail of the Arctic Ocean floor with this fascinating map. Includes an explanation of the technology behind the map's amazing cartography in the article "Exploring and Mapping the Seafloor." Published in January 1990, nearly a year after the Exxon Valdez spilled an estimated 11 to 30 million U.S. gallons of crude oil into Prince William Sound, as a companion to the article "Alaska's Big Spill - Can the Wilderness Heal?"