Deborah Kelley, a geologist at the University of Washington, Seattle, and co-principal investigator, says that, unlike most hydrothermal vents, what scientists are now calling the "Lost City Field" did not form during a volcanic eruption. The columns are also relatively devoid of marine life, she says, although they do support microbes. Other vents found in the Pacific, known as "black smokers," spew clouds of sulfur and iron-containing materials and host large communities of clams, shrimps, and other marine life.

Researchers are puzzling over the Lost City Field's origin. The vents are "not very hot, but there still must be a mechanism for how they are formed" in an area not affected by volcanic eruptions, says Susan Humphris, a geologist at the Woods Hole Oceanographic Institution in Massachusetts. She notes that the field seems to be associated with mantle, rather than volcanic rock, and probably contains large amounts of carbonate and silica, as well as methane and hydrogen. The fluid escaping from the vents, she believes, is seawater heated by rocks under the ocean floor.