why might geologists find Iceland a useful place to conduct research on seafloor spreading? scientists suggest that differences in density cause hot, plasticlike rock to be forced upward toward the surface, cool, and sink .
How do the land structures of Iceland help confirm seafloor spreading?
By the use of the sonar, Hess was able to map the ocean floor and discovered the mid-Atlantic ridge (mid-ocean ridge) . He also found out that the temperature near to the mid-Atlantic ridge was warmer than the surface away from it.
What evidence do geologists have for sea floor spreading?
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.
Why was discovering seafloor spreading so important?
Seafloor spreading disproves an early part of the theory of continental drift. Supporters of continental drift originally theorized that the continents moved (drifted) through unmoving oceans. Seafloor spreading proves that the ocean itself is a site of tectonic activity .
What is the importance of seafloor spreading?
Today it refers to the processes creating new oceanic lithosphere where plates move apart . Seafloor spreading replaces the lithosphere destroyed by subduction, and exerts important influences on Earth’s chemical and biological evolution.
What are 3 pieces of evidence that support 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 .
What are 4 pieces of evidence for seafloor 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 .
Is the Earth’s diameter getting bigger because of seafloor spreading?
New crust is continually being pushed away from divergent boundaries (where sea-floor spreading occurs), increasing Earth’s surface. But the Earth isn’t getting any bigger .
What are the features of seafloor?
Features of the ocean include the continental shelf, slope, and rise . The ocean floor is called the abyssal plain. Below the ocean floor, there are a few small deeper areas called ocean trenches. Features rising up from the ocean floor include seamounts, volcanic islands and the mid-oceanic ridges and rises.
Is the seafloor spreading accepted?
His basic idea of seafloor spreading along mid-oceanic ridges has well withstood the test of time. ... Unlike Wegener, he was able to see his seafloor-spreading hypothesis largely accepted and confirmed as knowledge of the ocean floor increased dramatically during his lifetime.
Which is the first step in seafloor spreading process?
1. A long crack in the oceanic crust forms at a mid ocean ridge . 2. Molten material rises and erupts along the ridge.
Where is active seafloor spreading occurring today?
Where is active sea floor spreading occurring today? Seafloor spreading is the movement of old rock that is being pushed by the new young oceanic crust. This would be a divergent since the plates are separating from each other. Active seafloor spreading is occurring at mid-ocean ridges .
What is the rate of seafloor spreading?
These age data also allow the rate of seafloor spreading to be determined, and they show that rates vary from about 0.1 cm (0.04 inch) per year to 17 cm (6.7 inches) per year.
How is seafloor spreading rate calculated?
To calculate the rate of the spreading, you need to use the following formula: the distance the sea floor moved divided by the length of time . This is an important concept for people in the earth sciences field. To complete these calculations, you will need maps showing the Earth’s crust.
Which of the following is evidence of seafloor spreading?
Several types of evidence supported Hess’s theory of sea-floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor , and the ages of the rocks themselves.
Which of the following is used as evidence of seafloor spreading?
Which of the following is used as evidence of seafloor spreading? Magnetic pole reversals .
