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Identify the claim put forward by Alfred Wegener to explain the mid-Atlantic ridge shown in Figure 1. Identify the evidence put forward by Alfred Wegener to explain the mid-Atlantic ridge shown in Figure 1. Identify the reasoning put forward by Alfred Wegener to explain the mid-Atlantic ridge shown in Figure 1. Claim: Construct an explanation that could account for the formation of the Mid-Atlantic Ridge. Your explanation should include a cause, mechanism and effect . Evidence: Use quantitative patterns to describe specific evidence from Figures 2-4 that helps support your explanation. Reasoning: Describe a chain of reasoning that connects the evidence described to your claim.
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Fresh rock is formed at the Mid-Atlantic RidgeDifference in the temperature of rock near the ridge.Rock forms from cooling magma and since the rock near the ridge is warmer it implies that this is newer rock.Cause: Plate pulls apart
Mechanism: Magma cools --> New rock forms --> Plate pulls apart --> New rock forms (repeat for millions of years)
Effect: Formation of the Mid-Atlantic ridge		Rock near the ridge is less that 10 my but near the edges of the Atlantic it is around 70 my old. As the magnetic pole reverses this is captured in the rock on either side of the ridge. Half spreading rate is consistent on either side of the ridge. The spreading rate is consistent on either side of the ridge.The movement of plates drives the stability and change of Earth systems. Since new rock formed at the ridge moves away from the center symmetrically the evidence locked in the rock (e.g. age, magnetic field) should also be symettric.
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The higher temperatures in the freshly exposed rock layers have caused depth variation in ocean basins.There is a 100 degree difference in temperature of the new rock layers compared to the sea floor.The fluid and hot rock rising from the depth caused the mid-Atlantic ridge. The mechanism is the rising magma cooling. The cause is the oceanic plate being pulled apart and move away from oceanic ridge. The effect is the formation of the mid Atlantic ridge.Spreading of 20 to 30 mm of crust per year by the mid Atlantic ridge. The age of the lithosphere right by the ridge is younger at an age of 0 to 10 m.y.If the crust is moving away from the cooling magma, then the lithosphere further away from the ridge would be older and it is approximately 150 m.y. according to figure 2.
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The mid-atlantic ridge is an area of sea-floor spreading where new rock is created.The rock near the ridge have higher temperatures than the older seafloor.Hot rock is rising to the surface to create new rock at the ridge. It ultimately cools down as it solidifies and moves away from the ridge.Cause: Magma rises to the surface to create rock at the mid-Atlantic ridge.
Mechanism: Convection in the mantle moves the plates apart in Earth's crust.
Effect: The plates spread apart at the surface and create new rock.		- Rock is from the Neogene/Quartenary epochs near the ridge (more recent), while the rocks get progressively older (Paleogene, Cretaceous, Jurrasic, etc.) as you move away.
- There is a symmetrical pattern in magnetic polarity reversals (ex. 2 stipes on either side of the ridge).		As hot magma in the mantle rises to the surface, it cools and forms rock at the Mid-Atlantic ridge. This rock then moves out from the ridge, following the convection cells happening under the surface in magma. This means that rock gets older as we move away from the ridge, as shown in Figure 2. We can also see this pattern shown in the magnetic reversals of rock since it is symmetrical compared to the ridge - all of the rock must have been created with the same polarity and then moved outward in each direction at relatively the same rate.
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Two oceanic plates are diverging and creating a ridge.There is an oceanic basin in the middle of the Altantic Ocean.There are convection cells of magma underneath the crust that are forcing the two plates to move away from one another.The magma underneath the crust creates giant convection cells, those cells separate the two diverging plates, a ridge is formed.The age of the lithosphere near the ridge is much younger than the age of the lithosphere furthest from the ridge. The half spreadinng rate is approximately 20-30 mm/yr as opposed to other areas around the world that are between 70-90 mm/yr. There is a repeating mirrored pattern of normal then reversed magnetic polarity from the ridge. There are three normal patterns and three reversed patterns.As the convection cells underneath the oceanic crust slowly causes the two plates to spread apart new crust forms in the middle. Magnetic polarity flips every few million years and as the crust forms there is evidence of that on either side of the ridge.
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The mid-Atlantic ridge can explain the phenomena of continental drift.The mid-Atlantic ridge is the zone in which the seafloor of the Atlantic is continuously tearing open and making space for the creation of new seafloor via volcanic activity.The temperature variations in freshly exposed rock layers are much warmer than the old strongly cooled seafloor cause variations in the depth of the ocean (or height of the seafloor). This is evidence of volcanic activity near the mid-Atlantic Ridge where new seafloor is created. The creation of the seafloor would have, over a very long period of geologic time, pushed the continents apart.Cause: Magma from beneath the ridge rises towards the surface.
Effect: The crust is ripped apart and new seafloor is created.
Mechanism: Rising plumes of magma beneath the crust causes high amount of volcanism at the ridge.
The age of the oceanic crust increases as you move away from the mid-ocean ridges.
Matching patterns of magnetic polarity within the rocks suggests simultaneous creation of the rocks on either side of the ridge- a good indication the spreading of the seafloor is symmetrical on either side.		I probably reasoned above.
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Alfred Wegener claims the mid-Atlantic ridge is an area where the ocean floor is spreading apart to form new land. Alfred Wegener recognized temperature differences on the sea floor.Where the new land is forming, warmer temperatures have been recorded. This new land is noted as "fluid and hot rock" rising from below Earth's surface. Cause: New land is forming
Mechanism: hot magma rises from the surface to form new land. This is turn pushes away the surrounding land outward in either direction.
Effect: Pushing plates to move away from each other to make room for new land		-Figure 2 shows values of 0-10 millions of year old at the center of the ridge, versus 70-80 millions of years old farther away from the ridge.
-In figure 3, the spreading rate is slower at the ridge (newly forming land occurs slower) 0-10 mm/yr.
-In figure 4, it shows		New land is forming slowly at the center of the ridge, indicating warmer temperatures. As this land forms, the plates begin to move apart at a slower rate, cooler temperatures
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