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What did the magnetic strips prove in seafloor spreading?
They proved that the seafloor was spreading.
Why was the theory of seafloor spreading rejected?
Because he wasn't able to prove it he said that if the ocean floor is moving, then the continents might be moving also
How does the mid ocean ridge magnetic signal prove sea floor spreading?
New oceanic crust is being created at the mid-ocean rift zones, a global divergent plate boundary system where uprising magma fills in the spaces being created by the pulling apart of plates. Part of the newly forming crust follows the direction of one plate, and part of the newly forming crust follows the direction of the other plate; therefore, the age of the rock created from the magma has a mirror image on either side of the rift. As new oceanic crust is continuously being formed at the mid-ocean ridges by upwelling molten rock, the direction of Earth's magnetic field is recorded in the rock by the orientation of magnetic minerals, which align themselves in the direction of the magnetic field before the rock completely crystallizes. Earth's magnetic field is known to change its orientation with frequency on a geologic time scale, thus a pattern of stripes of magnetic orientation is formed which can be detected with a magnetometer. The discovery of magnetic stripes on the seafloor have allowed researchers to provide additional proof that new crust is being created, and that magnetic reversals have occurred and will occur in the future. They tell us that over the course of thousands of years, Earth's polarity will reverse itself. The stripes are the magnetic "footprint" of Earth's shifting magnetic field.
How does seafloor spreading help scientists explain continental drift?
If one can prove that the sea floor spreads out from the mid oceanic ridges, then logically the continents must be moving apart to accommodate the spreading. Conversely there must also be places where sea floor is being destroyed if the Earth is to stay the same size.
How are the stripes of magnetism on each side of the ridge related?
These stripes, often called Zebra Stripes due to the alternating colors of the original magnetometer readings when the first observations were made. It is directly related to two processes...geomagnetic reversals and seafloor spreading. Seafloor spreading is easier to start with. Take the Mid-Atlantic Ridge running along the middle of the Atlantic Ocean. It is essentially a gap in the crust through which molten material from the mantle is pushed up through the crust. When it hits the water, the cold water rapidly cools it. As it continues to push out and harden, it very slowly pushes against the tectonic plates running along the ridge, causing them to spread apart. While they don't always run straight through the middle of an ocean, they will occur along plate boundaries. I've seen various maps showing tectonic plates that have arrows to show the direction of movement. Look for spreading ridges wherever you seen arrows pointed apart on these maps. Now, as the molten material comes out and hardnes, small amounts of magnetic elements crystalize in the rock as it forms, oriented in the direction of the Earth's magnetic field. Consider current rocks forming as stripe 1. Now, Earth's magnetic field fluctuates. This is normal and usually within small fluctuations. However, at times, it begins to break down. Eventually, when it does, it will rapidly flip over and a new magnetic field will begin to form in the reverse direction. This is Geomagnetic reversal. It used to be believed that it was quite random, though some scientists have argued that there is a pattern to it. It should also be noted that there isn't a specific time frame for how long they last or when they occur. Some will last for a few thousand years, some for a few tens of thousands of years, some for a few hundred thousand years. It varies quite a bit. We are still trying to understand this process, so we don't have definite answers as to what causes the whole process to work. Now, go back to the seafloor spreading. As the spreading occurs, imagine that a reversal occurs. You begin to see rocks forming with those magnetic fields pointing the other way. Stripe 2. The next reversal will bring it back to what our field looks like now...making stripe 3. And so on. When is the next reversal going to happen...well we don' t have an exact answer. But one estimate puts it between 3000 and 4000 A.D., provided that the current evidence of deterioration continues and isn't a short term effect. Since this is all a relatively new concept, we honestly don't exactly what characteristics we will see when it begins to happen, making it hard to predict. At least not yet. It should also be noted that the discovery of both seafloor spreading in the 1960's and geomagnetic reversals a bit earlier than that were the major pieces of evidence used to prove the theory of plate tectonics.
What did the magnetic strips prove in seafloor spreading?
They proved that the seafloor was spreading.
Did seafloor spreading prove the theory of continental drift?
Seafloor spreading helped prove the theory of continental drift. Pangea theory also helped.
What are 3 things of evidence that scientists have that prove the ocean is spreading?
1) seafloor spreading 2) continental drift 3 i only found 2
What is sea floor spreading and what evidence do we have to prove it is happening?
Magnetic minerals on the ocean floor.
What three pieces of evidence did Harry Hess gather to prove that seafloor spreading was taking place?
Three evidence that supports Harry Hess theory of Seafloor Spreading is; 1. Paleomagnetism. 2. Plate Tectonics. 3. Polar Wondering and Polar Reversal.
Why was the theory of seafloor spreading rejected?
Because he wasn't able to prove it he said that if the ocean floor is moving, then the continents might be moving also
What is seafloor spreading that ''helps'' the theory of continental drift?
How seafloor spreading helps to explain the theory of continental drift is that wegener couldn't explain why and waht force caused the continents to move and so seafloor spreading helps to explain the theory of continental drift because it shows the force that made the continents move and that was te only thing that wagener needed to prove his theory of continental drift............thanks
How did the study of paleomagnetism help prove wegener's hypothesis?
Before discovering that rocks are imprinted with the direction of magnetic orientation that exists at the time of their creation, no proof existed to confirm Wegener's hypothesis. When rocks were examined from both sides of the Mid-Ocean Ridge, the magnetic orientations were found to be mirror images of each other, indicating that the seafloor was spreading outward, and therefore pushing the continents apart.
How does the mid ocean ridge magnetic signal prove sea floor spreading?
New oceanic crust is being created at the mid-ocean rift zones, a global divergent plate boundary system where uprising magma fills in the spaces being created by the pulling apart of plates. Part of the newly forming crust follows the direction of one plate, and part of the newly forming crust follows the direction of the other plate; therefore, the age of the rock created from the magma has a mirror image on either side of the rift. As new oceanic crust is continuously being formed at the mid-ocean ridges by upwelling molten rock, the direction of Earth's magnetic field is recorded in the rock by the orientation of magnetic minerals, which align themselves in the direction of the magnetic field before the rock completely crystallizes. Earth's magnetic field is known to change its orientation with frequency on a geologic time scale, thus a pattern of stripes of magnetic orientation is formed which can be detected with a magnetometer. The discovery of magnetic stripes on the seafloor have allowed researchers to provide additional proof that new crust is being created, and that magnetic reversals have occurred and will occur in the future. They tell us that over the course of thousands of years, Earth's polarity will reverse itself. The stripes are the magnetic "footprint" of Earth's shifting magnetic field.
How does seafloor spreading help scientists explain continental drift?
If one can prove that the sea floor spreads out from the mid oceanic ridges, then logically the continents must be moving apart to accommodate the spreading. Conversely there must also be places where sea floor is being destroyed if the Earth is to stay the same size.
How are the stripes of magnetism on each side of the ridge related?
These stripes, often called Zebra Stripes due to the alternating colors of the original magnetometer readings when the first observations were made. It is directly related to two processes...geomagnetic reversals and seafloor spreading. Seafloor spreading is easier to start with. Take the Mid-Atlantic Ridge running along the middle of the Atlantic Ocean. It is essentially a gap in the crust through which molten material from the mantle is pushed up through the crust. When it hits the water, the cold water rapidly cools it. As it continues to push out and harden, it very slowly pushes against the tectonic plates running along the ridge, causing them to spread apart. While they don't always run straight through the middle of an ocean, they will occur along plate boundaries. I've seen various maps showing tectonic plates that have arrows to show the direction of movement. Look for spreading ridges wherever you seen arrows pointed apart on these maps. Now, as the molten material comes out and hardnes, small amounts of magnetic elements crystalize in the rock as it forms, oriented in the direction of the Earth's magnetic field. Consider current rocks forming as stripe 1. Now, Earth's magnetic field fluctuates. This is normal and usually within small fluctuations. However, at times, it begins to break down. Eventually, when it does, it will rapidly flip over and a new magnetic field will begin to form in the reverse direction. This is Geomagnetic reversal. It used to be believed that it was quite random, though some scientists have argued that there is a pattern to it. It should also be noted that there isn't a specific time frame for how long they last or when they occur. Some will last for a few thousand years, some for a few tens of thousands of years, some for a few hundred thousand years. It varies quite a bit. We are still trying to understand this process, so we don't have definite answers as to what causes the whole process to work. Now, go back to the seafloor spreading. As the spreading occurs, imagine that a reversal occurs. You begin to see rocks forming with those magnetic fields pointing the other way. Stripe 2. The next reversal will bring it back to what our field looks like now...making stripe 3. And so on. When is the next reversal going to happen...well we don' t have an exact answer. But one estimate puts it between 3000 and 4000 A.D., provided that the current evidence of deterioration continues and isn't a short term effect. Since this is all a relatively new concept, we honestly don't exactly what characteristics we will see when it begins to happen, making it hard to predict. At least not yet. It should also be noted that the discovery of both seafloor spreading in the 1960's and geomagnetic reversals a bit earlier than that were the major pieces of evidence used to prove the theory of plate tectonics.
Magnetic minerals prove Earth has had?
A liquid iron core that spins creating a magnetic field
