Plate Science
Science!
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P. 517 # 9, 10, 11, 12!
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9. Why does the thickness of ocean floor sediments increase the farther they are from a ridge?! -Thickness of ocean floor sediments increase the farther they are from a ridge because when new rocks form at the ridge, old rocks move away from the centre and this rocks stack along the end of sediments which pile up for long time that creates thick sediments,!
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10. How does sea floor spreading explain the movement of tectonic plates?!
- Sea floor spreading in movement of tectonic plates is called divergent, the separation of two plate. This can be proved because magma comes out from the fault of ridge which means plate has open and it’s realising the magma. Other reason, if diverging is happening at one point, that means converging is happening at other end of plate, for example Himalayan mountain range at
India and Nepal (converging) and other side of plate that contains India is having diverging which created Mid-Atlantic ridge.!
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11. Suppose a geologist is studying two distinct areas next to a spreading ridge. The magnetic direction of the minerals in the oldest area is opposite to the magnetic direction of minerals in the newest area.!
(a) Which area is closest to the centre of the ridge, the older or newer area? Explain.!
(b) What can the geologist conclude about Earth’s magnetic field during the time when the two areas formed?!
-a) the newer area is closest to the centre of the ridge because it’s where it creates new rocks and sediments through cooling of magma.!
-b) Geologist can conclude that polarity of two area is different because one has been created when polarity of the area was N, other one has been created when polarity of the area was S because polarity of Earth changes about 450,000 years in average. !
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12. In a few sentences, explain how information from paleoglaciation and paleomagnetism support the idea that continental plates have moved over the past several million years.!
- Paleoglaciation is one
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P. 517 # 9, 10, 11, 12!
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9. Why does the thickness of ocean floor sediments increase the farther they are from a ridge?! -Thickness of ocean floor sediments increase the farther they are from a ridge because when new rocks form at the ridge, old rocks move away from the centre and this rocks stack along the end of sediments which pile up for long time that creates thick sediments,!
!
10. How does sea floor spreading explain the movement of tectonic plates?!
- Sea floor spreading in movement of tectonic plates is called divergent, the separation of two plate. This can be proved because magma comes out from the fault of ridge which means plate has open and it’s realising the magma. Other reason, if diverging is happening at one point, that means converging is happening at other end of plate, for example Himalayan mountain range at
India and Nepal (converging) and other side of plate that contains India is having diverging which created Mid-Atlantic ridge.!
!
11. Suppose a geologist is studying two distinct areas next to a spreading ridge. The magnetic direction of the minerals in the oldest area is opposite to the magnetic direction of minerals in the newest area.!
(a) Which area is closest to the centre of the ridge, the older or newer area? Explain.!
(b) What can the geologist conclude about Earth’s magnetic field during the time when the two areas formed?!
-a) the newer area is closest to the centre of the ridge because it’s where it creates new rocks and sediments through cooling of magma.!
-b) Geologist can conclude that polarity of two area is different because one has been created when polarity of the area was N, other one has been created when polarity of the area was S because polarity of Earth changes about 450,000 years in average. !
!
12. In a few sentences, explain how information from paleoglaciation and paleomagnetism support the idea that continental plates have moved over the past several million years.!
- Paleoglaciation is one