Science: Mountains Under Water

The good ship Atlantis, an oceanographic research vessel, was back in Woods Hole, Mass, last week, after two months of seagoing mountaineering. Purpose of the voyage: to study the Mid-Atlantic Ridge, the submerged mountain range that divides the Atlantic Ocean—from Iceland almost to Antarctica. The range breaks the surface at only a few points (the Azores, Ascension Island, Tristan da Cunha). But if the Atlantic were drained dry, it would be one of the world’s most spectacular ranges, with several peaks 20,000 feet above the ocean floor.

No Continent Lost. The Atlantis (jointly sponsored by the Woods Hole Oceanographic Institution, Columbia University and the National Geographic Society) was equipped with sonic depth-finders, seismographs and other up-to-date gadgets of sea-bottom exploration. Most promising work was done by dredges, which brought up samples of rock. The rocks have not yet been studied, but Columbia’s Professor Maurice Ewing, head of the expedition, hopes that they will tell much about the geological origin of the underwater range.

In spite of its romantic name, the Atlantis did not search for relics of lost Atlantis, the fabled continent which the ancient Greeks believed sank beneath the Atlantic Ocean thousands of years ago. Most geologists do not take the Atlantis myth seriously.

Two Continents Strayed. But the expedition may throw light on a more important mystery: the origin of the continents. Some geologists believe that the continents are masses of granite floating in the heavier plastic basalt which underlies both the land and the ocean basins. Since they are floating, they may drift, like infinitely slow-moving icebergs. One theory holds that North and South America have drifted away from Europe and Africa, and that the curving crack between them has widened to form the Atlantic Ocean.

The Mid-Atlantic Ridge curves too. Its windings reflect with extraordinary accuracy the shape of the continents on either side.Obviously, there must be some relationship between the Ridge and the continents.

When the rocks brought back by the Atlantis are properly studied, they may prove that: 1) the Ridge was once part of the original continental mass, before the continents parted company; or 2) the underwater range is a young mountain system, slowly rising in the widening gap between the continents.