What evidence is there to support sea floor spreading?
Evidence of Sea Floor Spreading. Harry Hess’s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory. This evidence was from the investigations of the molten material, seafloor drilling, radiometric age dating and fossil ages, and the magnetic stripes.
What are three evidences of seafloor spreading?
Several types of evidence from the oceans supported Hess’s theory of sea-floor spreading-evidence from molten material, magnetic stripes, and drilling samples.
How is seafloor spreading explained and proven?
Seafloor spreading is the mechanism by which new seafloor lithosphere is constantly being created at mid-ocean ridges. This theory, introduced by Harry Hess, was proven as patterns of magnetic field polarity preserved in seafloor basalt and by age dating of the rocks.
What is the major evidence that sea floor spreading creates new lithosphere explain your answer?
What is the major evidence that sea-floor spreading creates new lithosphere? Explain your answer. Answers will vary. Sample answer: Molten rock at mid-ocean ridges has magnetized minerals that align with Earth’s magnetic field.
What are the four findings that support seafloor spreading theory?
In particular, four major scientific developments spurred the formulation of the plate-tectonics theory: (1) demonstration of the ruggedness and youth of the ocean floor; (2) confirmation of repeated reversals of the Earth magnetic field in the geologic past; (3) emergence of the seafloor-spreading hypothesis and …
What are the two supporting evidence of seafloor spreading theory?
Abundant evidence supports the major contentions of the seafloor-spreading theory. First, samples of the deep ocean floor show that basaltic oceanic crust and overlying sediment become progressively younger as the mid-ocean ridge is approached, and the sediment cover is thinner near the ridge.
What evidence helped give strong support for the hypothesis of seafloor spreading at mid-ocean ridges?
Earthquake zones [175 k] The recognition of such a connection helped confirm the seafloor-spreading hypothesis by pin-pointing the zones where Hess had predicted oceanic crust is being generated (along the ridges) and the zones where oceanic lithosphere sinks back into the mantle (beneath the trenches).
Is seafloor spreading good or bad?
Mid-ocean ridges and seafloor spreading can also influence sea levels. As oceanic crust moves away from the shallow mid-ocean ridges, it cools and sinks as it becomes more dense. This increases the volume of the ocean basin and decreases the sea level.
Who proved that the seafloor is spreading?
Harry H. Hess
The seafloor spreading hypothesis was proposed by the American geophysicist Harry H. Hess in 1960.
How does seafloor spreading provide evidence of past plate motion?
Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in the lithosphere. At a spreading center, basaltic magma rises up the fractures and cools on the ocean floor to form new seabed.
What is the key evidence found in the rocks of the seafloor that explains the mechanism processes of sea floor spreading?
The magnetism of mid-ocean ridges helped scientists first identify the process of seafloor spreading in the early 20th century. The specific magnetism of basalt rock is determined by the Earth’s magnetic field when the magma is cooling.