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Why are oceanic ridges more elevated than the rest of the sea floor?
Wiki User
∙ 11y ago
The mid-ocean ridge is a continuous mountain range formed from the uplift of thin crustal rocks from rising magma due to decompression melting of mantle material at divergent plate boundaries.
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Yes, that is how they are formed. They are high because, immediately below the ridge, the lithospheric mantle is almost nonexistent due to the heat of the rising mantle from the asthenosphere. The lack of cool mantle means that the relatively thin crust is the only thing "floating" on the mantle, and it is not very dense. As the lithosphere spreads (due to ridge-push force), the mantle below the lithosphere crust begins to cool and when it cools sufficiently it becomes, by definition, lithospheric mantle. This mantle is dense and grows thicker as the plate spreads further from the ridge and has more time to cool. The density of this, and the increased mass, is relatively higher than what is essentially only the crust at the ridge. Because it is more dense and "heavier," it sinks down further into the asthenosphere, causing the ridge itself to be high on the sea floor.
Wiki User
∙ 11y ago
Wiki User
∙ 10y agoThe mid-ocean ridge is a continuous mountain range formed from the uplift of thin crustal rocks from rising magma due to decompression melting of mantle material at divergent plate boundaries.
___
Yes, that is how they are formed. They are high because, immediately below the ridge, the lithospheric mantle is almost nonexistent due to the heat of the rising mantle from the asthenosphere. The lack of cool mantle means that the relatively thin crust is the only thing "floating" on the mantle, and it is not very dense. As the lithosphere spreads (due to ridge-push force), the mantle below the lithosphere crust begins to cool and when it cools sufficiently it becomes, by definition, lithospheric mantle. This mantle is dense and grows thicker as the plate spreads further from the ridge and has more time to cool. The density of this, and the increased mass, is relatively higher than what is essentially only the crust at the ridge. Because it is more dense and "heavier," it sinks down further into the asthenosphere, causing the ridge itself to be high on the sea floor.
Wiki User
∙ 11y agoRidges are elevated because the rocks are hot.
Wiki User
∙ 11y agoBecause they want to u got a problem huh than fight me
Wiki User
∙ 10y agoMagma is upwelling, pushing up the floor like a volcanoe
Wiki User
∙ 11y agoLithosphere created at the ridge is hot
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Places where new sea floor is being created?
New oceanic crust is formed when volcanic activity disrupts the seafloor at the mid- ocean ridge. When this occurs it is referred to as oceanic spreading.
Are oceanic rocks billion years old?
No. Oceanic crust is recycled into the mantle through a process called subduction and new ocean floor is formed at mid-ocean ridges. None of the ocean floor is more than about 180 million years old. Some rocks on the continents are billions of years old.
Why is earth not getting larger even though new lithosphere is constantly being added at the oceanic ridges?
Rock creation is part of The Rock Cycle. Rocks are destroyed by erosion--they provide new material for sedimentary rocks. Rocks are created at rift zones in the crust--they are also plowed into the mantle at subduction zones and melt.
What is continental and oceanic crust?
The continental crust is the land. The oceanic is under the ocean.
Are continental plates more buoyant than oceanic plates?
Continental lithospheric plates are more buoyant than oceanic plates, yes.
Places where new sea floor is being created?
New oceanic crust is formed when volcanic activity disrupts the seafloor at the mid- ocean ridge. When this occurs it is referred to as oceanic spreading.
Subduction occurs where the oceanic crust bends down toward the mantle at a(n)?
Seafloor spreading occurs along mid-ocean ridges. Mid-ocean ridges are large mountain ranges on the ocean floor. The shifting in the rock causes the seafloor to spread and allows magma to bubble and form more mountains on the ocean floor.
Are oceanic rocks billion years old?
No. Oceanic crust is recycled into the mantle through a process called subduction and new ocean floor is formed at mid-ocean ridges. None of the ocean floor is more than about 180 million years old. Some rocks on the continents are billions of years old.
What evidence supports the theory of plate?
The shape of the continents, the distribution of earthquakes, the symmetric magnetic banding of the sea floor ether side of the mid oceanic ridges, the mid oceanic ridges, back arc basins, deep sea trenches, the fiery ring of the Pacific, The distribution and chemistry of volcanoes, atolls, paleo magnetism, fossil evidence and the distribution of species. (there may be more evidence).
What evidence supports the theory of plate tectonics?
The shape of the continents, the distribution of earthquakes, the symmetric magnetic banding of the sea floor ether side of the mid oceanic ridges, the mid oceanic ridges, back arc basins, deep sea trenches, the fiery ring of the Pacific, The distribution and chemistry of volcanoes, atolls, paleo magnetism, fossil evidence and the distribution of species. (there may be more evidence).
Why is the oceanic crust is more active than the continental crust?
This is because the Oceanic Crust is denser and thinner than the Continental Crust and is actively being created by the forces of the magma at different mid-oceanic ridges.
Why continental rock is younger than oceanic rock?
The Oceanic Plates are younger than the continental because they are "recycled"; think of the oceanic ridges, such as the mid Atlantic oceanic ridge, that is where a hot spot under diverging plates (plates moving apart) push magma up, causing new young ocean floor to spread from this spot, and pushing the old floor into trenches and other continents, being destroyed. Another point to remember is that the ocean crust is thicker the farther away from the ridge; this is because it has had more time to build itself up compared to the more thin young crust.
What type of magmatic activity is characteristic of mid oceanic ridges?
At mid-oceanic ridges, plates are pulled apart in two separate directions. This creates a gap (rift valley), allowing for warm, buoyant magma to rise to the surface and cool. As the magma cools, it creates ridges along the rift valleys. The elevation is caused by the excess amount of newly created, less dense oceanic crust. This crust occupies more volume, which causes it to be higher up than the surrounding, older crust.
What is the oceanic crust?
The oceanic crust is part of the crust that is made fully out of basaltic rock and is several times thinner than the continental crust which is made out of granitic rock. Oceanic crust underlies Earth's oceans and is produced at divergent plate boundaries which are commonly referred to as mid-ocean ridges. As it grows from infilling magma and spreads away from the ridges, it will becomes cooler, thicker, and more dense, and will eventually sink into the mantle.
Is the ocean the oceanic crust?
The oceanic crust is part of the crust that is made fully out of basaltic rock and is several times thinner than the continental crust which is made out of granitic rock. Oceanic crust underlies Earth's oceans and is produced at divergent plate boundaries which are commonly referred to as mid-ocean ridges. As it grows from infilling magma and spreads away from the ridges, it will becomes cooler, thicker, and more dense, and will eventually sink into the mantle.
Why does continental crusts stand higher on the mantle then oceanic crust?
Because Oceanic crust is more dense and the Continental Crust is mountains which are a lot taller than sea floor.
When two oceanic plates diverge?
Volcanoes form from the exposure of lava in the Earth's mantle. B Actually this is wrong, it forms a mid oceanic ridge. Do some more research next time. C. Actually it forms a Mid-Ocean Trench both of you do better reserch next time.
