Last Updated on October 1, 2022 by amin
What makes up the lithosphere?
Cutaway Earth The lithosphere is the rocky outer part of the Earth. It is made up of the brittle crust and the top part of the upper mantle. The lithosphere is the coolest and most rigid part of the Earth.
How do magnetic anomaly patterns on the ocean floor best serve as evidence for seafloor spreading?
magnetic polarity reversals. How do magnetic anomaly patterns on the ocean floor best serve as evidence for seafloor spreading? The symmetry on either side of mid-ocean ridges shows that new crust is created and then split apart.
What is evidence of seafloor spreading Brainly?
One piece of evidence of seafloor spreading is a mid-ocean ridge. Explanation: The Mid-Atlantic Ridge is a mountain system formed by plate tectonics on the seafloor.
What is the major evidence that seafloor 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.
How do evidence of continental drift and seafloor spreading prove that the plates move?
In 1915 Wegener proposed his continental drift theory. He said that the continents floated atop the mantle-a heavier denser layer of rocks deep within the earth. … This evidence led early marine geologists to deduce that the mid-ocean ridges were formed by seafloor volcanoes.
How do magnetic reversals provide evidence of the seafloor spreading?
Magnetic reversals occur every so often. When they happen the Earth’s magnetic field reverses its polarity. In other words north becomes south and south becomes north. Magnetic reversal proves seafloor spreading because we can see the polarity of the Earth’s magnetic field in rocks.
Which is evidence that supports the dynamo theory?
The correct answer is option B) Earth’s core contains a large amount of iron. The dynamo theory explains how celestial bodies develop magnetic fields. According to the theory the magnetic field is generated by the motion of a rotating and electrically conducting fluid.
What is lithosphere in short answer?
Lithosphere is the solid crust or the hard top layer of the earth. It is made up of rocks and minerals. It is covered by a thin layer of soil. It is an irregular surface with various landforms such as mountains plateaus desert plains valleys etc.
Sea Floor Spreading Lecture
What are the steps in the process of sea-floor spreading?
Terms in this set (7)
- Magma comes out of the rift valley.
- Magma cools to rock and hardens.
- Rock is pushed away as new rock is formed at MOR.
- Oceanic crust and continental crust meet at the trench.
- Oceanic crust bends down under the continental crust.
- Gravity pulls rock towards mantle.
- Rock melts to mantle.
How do ocean ridges and deep sea trenches support the theory of seafloor spreading?
How do ocean ridges and deep-sea trenches support the theory of seafloor spreading? THE THEORY OF SEAFLOOR SPREADING STATES THAT OCEAN RIDGES ARE PLACES WHERE NEW OCEAN CRUST IS FORMED TRENCHES ARE PLACES WHERE IT IS DESTROYED. … THESE DATA ARE CONSISTENT WITH NEW CRUST FROMING AT RIDGES AND BEING DESTROYED AT TRENCHES.
What observations of the ocean floor supported the sea floor spreading hypothesis?
These observations are:
- The seafloor has a large mountain range running through it. Deep trenches are found far from the ridges. …
- The magnetic polarity of the seafloor changes. The center of the ridge is of normal polarity. …
- The youngest seafloor is at the ridge. The oldest is farthest from the ridge.
What causes the formation of new seafloor?
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 evidence further supports the theory of seafloor spreading quizlet?
Evidence from molten material magnetic strips and drilling samples support the theory of sea-floor spreading.
Which statement describes the cyclic nature of seafloor spreading?
The Statements that describe the cyclic nature of seafloor spreading are as follows New oceanic crust is formed.
What Is The Major Evidence That Sea-floor Spreading Creates New Lithosphere? Explain Your Answer.?
The record of magnetic reversals is carried away from each side of the spreading center of a mid-ocean ridge showing that the molten rock is creating new lithosphere.
FOUR DOMAINS OF THE EARTH | Atmosphere | Lithosphere | Hydrosphere | Biosphere | Dr Binocs Show
What are two pieces of evidence for 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.
What evidence was presented by geologists in the 1960s that sea floor spreading actually takes place?
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 …
How does Earth magnetic field provide evidence for seafloor spreading?
A polarity reversal means that the magnetic North flips to where we know the South Pole is. … This creates a symmetrical pattern of magnetic stripes of opposite polarity on either side of mid-ocean ridges. These patterns of stripes provide the history of seafloor spreading.
Science 10: Lesson 5 Seafloor Spreading
What is the major difference between lithosphere under a continent compared to under the ocean floor?
Layers that are less dense such as the crust float on layers that are denser such as the mantle. Both oceanic crust and continental crust are less dense than the mantle but oceanic crust is denser than continental crust. This is partly why the continents are at a higher elevation than the ocean floor.
What is seafloor spreading quizlet?
Seafloor Spreading. The process by which molten materials add new oceanic crust to the ocean floor. Only $35.99/year. Deep Ocean Trench. A deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle.
What causes seafloor spreading quizlet?
During sea-floor spreading magma erupts along a mid-ocean ridge to form new oceanic lithosphere. The floor then moves away from the ridge often toward a trench at the edge of the ocean basin. … The pattern shows that ocean floor forms along mid-ocean ridges and then moves away from the ridge.
How does seafloor spreading affect the lithosphere?
The denser lithospheric material then melts back into the Earth’s mantle. Seafloor spreading creates new crust. Subduction destroys old crust. The two forces roughly balance each other so the shape and diameter of the Earth remain constant.
Which feature of Earth is created at mid-ocean ridges Brainly?
Explanation: Mid-ocean ridges occur along divergent plate boundaries where new ocean floor is created as the Earth’s tectonic plates spread apart. As the plates separate molten rock rises to the seafloor producing enormous volcanic eruptions of basalt.
What discovery about the ocean floor is associated with the seafloor spreading in 1960?
Hess in 1960. On the basis of Tharp’s efforts and other new discoveries about the deep-ocean floor Hess postulated that molten material from Earth’s mantle continuously wells up along the crests of the mid-ocean ridges that wind for nearly 80 000 km (50 000 miles) through all the world’s oceans.
How do Earth’s magnetic pole reversals provide evidence for plate tectonics apex?
Rocks have no magnetic material so they are unaffected by reversals. How do Earth’s magnetic pole reversals provide evidence for plate tectonics? … Rocks become more magnetized as you move away from ocean ridges.
Which statement describes one event that happens at deep ocean trenches?
The destruction of crust occurs at deep-sea trenches. Oceanic rocks are pillow-shaped when formed.
What makes up the lithosphere Brainly answer?
Answer: The lithosphere is the solid outer part of the Earth. The lithosphere includes the brittle upper portion of the mantle and the crust the outermost layers of Earth’s structure. It is bounded by the atmosphere above and the asthenosphere (another part of the upper mantle) below.
What is seafloor spreading and how is it evidence of plate movement?
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.
How new lithosphere is produced by the sea floor spreading that occurs at a mid-ocean ridge?
Seafloor spreading is the process by which new oceanic lithosphere forms at mid-ocean ridges. As tectonic plates move away from each other magma rises from Earth’s interior. It then cools and solidifies in the center of the ridge. The rising magma pushes up between the plates and drives them further apart. See also what on earth meaning
What are the prominent evidences in support of sea floor spreading theory?
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. See also what causes mountain building
Is fossil evidence of seafloor spreading?
Why are fossils found in ocean sediments no more than 180 million years old? … This “recycling” process later named “seafloor spreading ” carries off older sediment and fossils and moves the continents as new ocean crust spreads away from the ridges.
What are the 3 types of evidence for 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 lithosphere formed Wikipedia?
When a continental plate comes together with an oceanic plate at a subduction zones the oceanic lithosphere always sinks beneath the continental. New oceanic lithosphere is constantly being produced at mid-ocean ridges and is recycled back to the mantle at subduction zones. See also what are different types of fossils
How was sea floor spreading tested as a hypothesis?
Since the oldest oceanic crust was found at the edges of the trenches Hess hypothesized that the seafloor subducts into Earth’s interior at the trenches to be recycled in the mantle. As oceanic crust forms and spreads moving away from the ridge crest it pushes the continent away from the ridge axis.