EVERYDAY SCIENCE

Detailed explanation-1: -He realized that the Earth’s crust had been moving away on each side of oceanic ridges, down the Atlantic and Pacific oceans, that were long and volcanically active. He published his theory in History of Ocean Basins (1962), and it came to be called “seafloor spreading.”

Detailed explanation-2: -Harry Hess was a geologist and Navy submarine commander during World War II. Part of his mission had been to study the deepest parts of the ocean floor. In 1946 he had discovered that hundreds of flat-topped mountains, perhaps sunken islands, shape the Pacific floor.

Detailed explanation-3: -Harry Hess: One of the Discoverers of Seafloor Spreading.

Detailed explanation-4: -Seafloor spreading was discovered by Harry Hess who used maps created by sonar readings of the ocean floor. He noticed long chains of underwater mountains with the rift valley at their centers (now known as mid-ocean ridges).

Detailed explanation-5: -This seafloor spreading hypothesis had been proposed a few years earlier by Harry Hess, a petrologist at Princeton University, and Robert Dietz, an oceanographer in the US Coast and Geodetic Survey (the federal department that made maps of the oceans and US coastlines).