Alvin's manipulator reaches down toward a black smoker chimney, seen through the sub's view port at 17 degrees south on the East Pacific Rise.

Join Karen Von Damm on a voyage to the bottom of the sea

By Robert Kunzig

See also:
Going Down

Once or twice a year, Karen Von Damm boards a ship bound for a place not on ordinary maps, a place known often by its latitude--21 degrees north, 9 degrees north, 21 degrees south. Arrived at that place, in the middle of an ocean, she climbs into a small submarine and dives straight down, a mile and a half or sometimes two. If things work out, she lands on top of an active volcano, dotted with hot springs. Maybe she sees tube worms--tall as ripe corn with blood-red plumes waving in the current--or clouds of shrimp swarming like bees around rock chimneys tall as houses. Out of the chimneys billows 700 degrees Fahrenheit (371 degrees Celsius) water that is black with iron. Sometimes the roiling cloud engulfs the submarine and blacks out its portholes. Von Damm is in her element.

The midocean ridge, the chain of seafloor volcanoes that wraps around the planet for 40,000 miles, is a different world. Karen Von Damm has been going there for more than 20 years, and for the last 10 she has been leaving from Durham, where she is professor of geochemistry at UNH. She is the world's leading expert on "black smokers," as those seafloor chimneys are called. They were first discovered in the spring of 1979 at 21° North on the East Pacific Rise, at the mouth of the Gulf of California. In the fall of that year, Von Damm visited the site with the first scientific team to collect chemical samples at a black smoker. Those samples changed our understanding of the oceans' chemistry forever.