Which information did the Glomar Challenger study in 1968?
A. the rate of seafloor spreading
B. the direction of seafloor spreading
The Correct Answer and Explanation is:
The correct answer is A. the rate of seafloor spreading.
The Glomar Challenger was a deep-sea research and drilling vessel that revolutionized our understanding of plate tectonics and oceanography. It set sail in 1968 as part of the Deep Sea Drilling Project (DSDP), and one of its main missions was to investigate the theory of seafloor spreading, which was a relatively new concept at the time.
Seafloor spreading is the process by which new oceanic crust is formed at mid-ocean ridges and slowly moves outward on either side, pushing older crust away from the ridge. This theory, proposed by Harry Hess in the 1960s, provided crucial evidence for the larger theory of plate tectonics. However, the rates at which this spreading occurred were still uncertain when the Glomar Challenger began its expeditions.
By drilling core samples from the ocean floor at various locations and analyzing the sediment layers, scientists aboard the Glomar Challenger were able to measure the age of the rocks at different distances from mid-ocean ridges. Their findings showed that the age of the oceanic crust increased symmetrically as one moved away from the ridges, providing direct evidence that new crust was being formed at the ridges and pushing older crust outward. This provided key confirmation of seafloor spreading.
The study of the sediment and fossil layers within the core samples allowed scientists to estimate the rate at which the seafloor was spreading. They discovered that seafloor spreading occurred at different rates in different parts of the world, typically ranging from 1 to 10 centimeters per year. The Glomar Challenger’s findings were instrumental in solidifying the theory of plate tectonics, transforming our understanding of Earth’s geological processes.
Therefore, the Glomar Challenger was essential in providing the scientific data necessary to determine the rate of seafloor spreading.