When the researchers went back to Finn's "stump" 3 1/2 days later, they found that a new cone had grown about 4 1/2 feet high. "That really surprised us," Delaney said. After two weeks, another visit to install instruments showed that it was already 15 feet high.
The laboratory studies have also yielded some surprises, he noted. Although they expected the cones to be composed primarily of metal sulfides, the scientists found that the first one they studied "was just loaded with clay. . . . We never expected it to be caught in the chimneys," Delaney said.
They also discovered that the chimneys grow larger when scalding water seeps through cracks in the chimney, depositing its dissolved minerals on the outside of the structures.
One of the chimneys will be placed on display this winter at the American Museum of Natural History in New York City. The expedition will also be the subject of a documentary next spring on PBS.
More information about the expedition can be obtained at the Web sites of the American Museum of Natural History (www.amnh.org), the University of Washington (www.ocean.washington.edu/outreach/revel) and PBS television (www.pbs.org/wgbh/nova/abyss).
