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What other than earth is known to have magnetic pole reversals?
Darksyde
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Does earth's magnetic field only affect other planets?
No. Earth's magnetic field only affects earth, not other planets.
How does magnetic reversals found in the sea floor rocks cause continental drift?
Magnetic reversals found in the sea floor do not cause continental drift. It does however provide evidence that sea floor spreading occurs (and hence is evidence for the theory of plate tectonics). This is because the iron rich minerals in basaltic rocks (such as magnetite) are at high temperatures when they are first intruded into the crust and at these high temperatures they record the orientation of Earth's magnetic field. As they cool, this record of the orientation of the magnetic field is "locked" in place. The Earth's magnetic field is known to "reverse polarity" - the north and south magnetic poles switch over time and so the orientation of the magnetic field in newly cooled rocks will change to match this. Geophysicists had recognised that there were alternating bands of rocks with these reversed orientations of the magnetic field. These bands ran parallel to the Mid-Ocean-Ridges. In the 1960s after significant magnetic survey work was undertaken it was realised that the alternating bands on one side of the oceanic ridge were a mirror image to the bands on the other side. So why is this evidence for sea floor spreading / plate tectonics? Well it was realised that if the newly intruded rock was to move away from the Mid-Ocean-Ridge (M-O-R) and be replaced with new younger rock, this rock would continue to record the orientation of the Earth's magnetic field as and when reversals occurred. As such this would lead to the stripes of alternating magnetic orientation that are symmetrical about the M-O-R. As such movement of the plates away from a M-O-R and the reversals of Earth's magnetic field best explained the presence of these bands and so confirmed the idea that sea floor spreading was occurring. For more information, please see the related link.
How magneteism is used to support the theory of seafloor spreading?
During the Second World War, linear bands of positive and negative magnetic anomolies were found in the ocean floor, stretching for hundreds of miles, with an almost perfect symmetry either side of mid-ocean ridges. It was realised that these anomalies were evidence of periodic reversals of the earth's magnetic field. Molten basalt had been magnetised in the direction of the field and then cooled to 'fossilise' that direction. Each time the earth's magnetic field reversed, a stripe was added to the 'bar-code'. By dating onshore lava flows where magnetic reversals had occurred, a timescale of magnetic reversals was built up. It then became clear that, in the undersea anomalies, the youngest rocks were near the ridge, while the oldest were farther away and nearest the continents. Either side of the ridge, stripes of exactly the same age could be matched with each other. There was already evidence of continental drift, but this new evidence helped to explain how the earth's crust is moving and how the sea floor is spreading.
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.
Why do magnetic strips appear on seafloor?
Magnetic strips appear on the seafloor because it spreads apart, forming new rocks that have a magnetic properties.
What are Other than earth is also known to have magnetic pole reversals?
The sun (correct for Apex) :)
How do magnetic reversals provide evidence for sea-floor spreading?
The presence of magnetic domains of alternating orientation parallel to the plate boundaries.
Does earth's magnetic field only affect other planets?
No. Earth's magnetic field only affects earth, not other planets.
How does magnetic reversals found in the sea floor rocks cause continental drift?
Magnetic reversals found in the sea floor do not cause continental drift. It does however provide evidence that sea floor spreading occurs (and hence is evidence for the theory of plate tectonics). This is because the iron rich minerals in basaltic rocks (such as magnetite) are at high temperatures when they are first intruded into the crust and at these high temperatures they record the orientation of Earth's magnetic field. As they cool, this record of the orientation of the magnetic field is "locked" in place. The Earth's magnetic field is known to "reverse polarity" - the north and south magnetic poles switch over time and so the orientation of the magnetic field in newly cooled rocks will change to match this. Geophysicists had recognised that there were alternating bands of rocks with these reversed orientations of the magnetic field. These bands ran parallel to the Mid-Ocean-Ridges. In the 1960s after significant magnetic survey work was undertaken it was realised that the alternating bands on one side of the oceanic ridge were a mirror image to the bands on the other side. So why is this evidence for sea floor spreading / plate tectonics? Well it was realised that if the newly intruded rock was to move away from the Mid-Ocean-Ridge (M-O-R) and be replaced with new younger rock, this rock would continue to record the orientation of the Earth's magnetic field as and when reversals occurred. As such this would lead to the stripes of alternating magnetic orientation that are symmetrical about the M-O-R. As such movement of the plates away from a M-O-R and the reversals of Earth's magnetic field best explained the presence of these bands and so confirmed the idea that sea floor spreading was occurring. For more information, please see the related link.
How magneteism is used to support the theory of seafloor spreading?
During the Second World War, linear bands of positive and negative magnetic anomolies were found in the ocean floor, stretching for hundreds of miles, with an almost perfect symmetry either side of mid-ocean ridges. It was realised that these anomalies were evidence of periodic reversals of the earth's magnetic field. Molten basalt had been magnetised in the direction of the field and then cooled to 'fossilise' that direction. Each time the earth's magnetic field reversed, a stripe was added to the 'bar-code'. By dating onshore lava flows where magnetic reversals had occurred, a timescale of magnetic reversals was built up. It then became clear that, in the undersea anomalies, the youngest rocks were near the ridge, while the oldest were farther away and nearest the continents. Either side of the ridge, stripes of exactly the same age could be matched with each other. There was already evidence of continental drift, but this new evidence helped to explain how the earth's crust is moving and how the sea floor is spreading.
How will magnetic minerals align in a rock if earth has no magnetic field?
Assuming there is no Earth magnetic field, and no other significant magnetic fields, they will not allign in any preferred direction.
How does a sun flare effect earth and other planets?
solar flare... sends out a blast of magnetic field, it has been known to cause power outages on the planet of Earth
What does the earth's magnetic field not affect?
other planets
Which planet other than earth has magnetic field?
pagal
What pulls the South Pole of a magnetic compass?
The south pole of a magnetic compass is pulled towards the Earth's north magnetic pole, and away from Earth's south magnetic pole. Or towards and away the corresponding poles of any other magnet. Note that Earth's NORTH magnetic pole is close to the SOUTH pole.
Will a compass always work?
No. I assume you mean a magnetic compass. A magnetic compass reacts to magnetic fields; the magnetic south pole of Earth is not exactly at the geographic north pole, so at some points of the Earth's surface, the magnetic compass will actually point south instead of north. Also, a magnetic compass will be influenced by other magnetic fields, e.g., current-carrying wires.No. I assume you mean a magnetic compass. A magnetic compass reacts to magnetic fields; the magnetic south pole of Earth is not exactly at the geographic north pole, so at some points of the Earth's surface, the magnetic compass will actually point south instead of north. Also, a magnetic compass will be influenced by other magnetic fields, e.g., current-carrying wires.No. I assume you mean a magnetic compass. A magnetic compass reacts to magnetic fields; the magnetic south pole of Earth is not exactly at the geographic north pole, so at some points of the Earth's surface, the magnetic compass will actually point south instead of north. Also, a magnetic compass will be influenced by other magnetic fields, e.g., current-carrying wires.No. I assume you mean a magnetic compass. A magnetic compass reacts to magnetic fields; the magnetic south pole of Earth is not exactly at the geographic north pole, so at some points of the Earth's surface, the magnetic compass will actually point south instead of north. Also, a magnetic compass will be influenced by other magnetic fields, e.g., current-carrying wires.
How the compass works?
The Earth has a magnetic field approximately like a magnetic dipole, with the magnetic field S pole near the Earth's geographic north pole and the other magnetic field N pole near the Earth's geographic south pole. A compass can determining direction relative to the Earth's magnetic poles by using a magnetized pointer (usually marked on the North end) which is pivoting free to align itself with Earth's magnetic field.
