Why is seafloor spreading 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.

Was the seafloor spreading theory accepted?

The theory was strengthened further when dating studies showed that the seafloor becomes older with distance away from the ridge crests. 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.

Why were the ideas of Wegener and Hess not accepted by other scientists during their time?

Alfred Wegener produced evidence in 1912 that the continents are in motion, but because he could not explain what forces could move them, geologists rejected his ideas. Almost 50 years later Harry Hess confirmed Wegener’s ideas by using the evidence of seafloor spreading to explain what moved continents.

What are the 2 evidence 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. This evidence also led sci- entists to look again at Wegener’s theory of continental drift.

How does seafloor spreading affect continents?

Seafloor spreading creates new oceanic crust at a mid-ocean ridge. On one side, the oceanic crust is subducted below the continental crust. On the other side, the two plates collide in a transform boundary, which is a horizontal type of movement. The latter is the closest we really come to continents drifting.

What are the consequences of COnvergent oceanic and continental plates?

Effects of a convergent boundary between an oceanic and continental plate include: a zone of earthquake activity that is shallow along the continent margin but deepens beneath the continent, sometimes an ocean trench forms immediately off shore of the continent, a line of volcanic eruptions a few hundred miles inland …

What was the main reason why Alfred Wegener’s theory about the movement of the continents was dismissed in 1912?

Wegener’s inability to provide an adequate explanation of the forces responsible for continental drift and the prevailing belief that the earth was solid and immovable resulted in the scientific dismissal of his theories.

What was the one weakness of the theory of continental drift?

The problem that was used to reject Continental Drift is that the theory had no mechanism or explanation for what could cause the movement of the massive continents.

How did the seafloor spreading theory vindicate Wegener?

Sea floor spreading is the phenomena of new sea floor being created through mid-ocean ridges. Wegener proposed that the continents themselves move, which is untrue. Sea floor spreading caused the break up of Pangea, which prompted Wegener to add this in support of his continental drift theory.

How did the seafloor spreading theory affect the development of the theory of plate tectonics?

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. Older rocks will be found farther away from the spreading zone while younger rocks will be found nearer to the spreading zone.

What evidence helped support the theory of seafloor spreading?

Evidence for Sea-Floor 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. This evidence led scientists to look again at Wegener’s hypothesis of continental drift.

What is Harry Hess’s theory of seafloor spreading?

This theory later became known as ‘Sea Floor Spreading’. Hess envisaged that oceans grew from their centres, with molten material (basalt) oozing up from the Earth’s mantle along the mid ocean ridges. This created new seafloor which then spread away from the ridge in both directions.

How would you describe the process of seafloor spreading?

What Happens During the Process of Seafloor Spreading? History. Scientists originally believed that drifting was an occurrence exclusive to continents through continental drifts. Geographic Features. The process of seafloor spreading leads to the formation of numerous geographical features which can be terrestrial, sub-terrestrial, or marine features. Mid-Ocean Ridges.

How do scientists prove the seafloor is spreading?

Evidence of Sea Floor Spreading Molten material. Hess’s discovery on the warmer temperature near the mid-Atlantic ridge when he began the ocean mapping, led to his evidence about the molten material underneath the ocean. Seafloor drill. The seafloor drilling system led to the evidence that supports the seafloor-spreading hypothesis. Radiometric age dating and fossil ages.