After doing researches on fossils and rock, scientist studied the ocean floor to further support the continental drift theory. Harry Hess, a navy officer, used sonar technology to gather information about the ocean floor. Hess presented a theory, known as “sea floor spreading” to explain the drifting of continents. Upon exploring the surface of the ocean, he found that earth’s crust had been moving. “He suggested that the new ocean crust was created at the ridges, split apart, moved away from the ridges and, later disappeared back into the deep Earth at trenches.” (Thurman, Trujillo, 44). He also suggested that the oceans were low in depth at the center and discovered that the mid ocean ridges “rises more than 2.5 kilometer (1.5 miles) above