Other holes drilled into the Juan de Fuca ridge haven't been equipped with devices known as CORKS--steel plugs that close the hole at the seafloor and dangle a long string of instruments for measuring temperature and pressure down the hole. Scientists, including Earl E. Davis of the Geological survey of Canada on this voyage, visit these sites periodically with submarines such as Alvin and extract the computerized data collected by the sensors. The Juan de Fuca ridge contains the largest concentration of these monitored boreholes in the world's oceans.
During this brief voyage, the scientists traveling to the seafloor in Alvin will take samples of water and mineral deposits, collect specimens of the unique creatures that live near hydrothermal vents, and try to solve one intriguing mystery: The water coming from high-temperature vents glows with light, and no one knows why. But Alan Chave, this expedition's chief scientist, is hoping that a specially designed camera, constructed by Anthony Tyhson of Bell Labs, will provide some clues. In any case, Alvin is almost certain to bob to the surface at the end of each dive with a fascinating story to tell.