Admin Table of Contents
- 1 Does subduction of oceanic crust happen at a mid-ocean ridge?
- 2 What is the difference between mid-ocean ridges and subduction zones?
- 3 Why does the oceanic crust sink beneath the continental crust at the subduction zone?
- 4 When an oceanic crust converges with another oceanic crust A?
- 5 Why does the lithosphere thicken as it moves away from a mid-ocean ridge?
- 6 What is the process by which new oceanic lithosphere is formed?
Does subduction of oceanic crust happen at a mid-ocean ridge?
New seafloor is generated from the upper mantle at the mid-oceanic ridges, spreads laterally outward, and is eventually subducted, or consumed, at the margins of ocean basins. Subduction may also occur between two regions of oceanic crust, with older, denser sections underthrusting younger, less-dense ones.
What is the difference between mid-ocean ridges and subduction zones?
Mid-ocean ridge volcanoes tend to be linear and look like long, low ridges, while volca- noes at subduction zones tend to be cone- shaped and isolated. Volcanoes at subduction zones often erupt explosively; volcanoes at mid-ocean ridges usually do not.
Is oceanic lithosphere destroyed at ocean ridges?
New oceanic lithosphere is formed by frequent volcanic eruptions along the length of mid-ocean ridges and is pushed outward from them gradually. Old oceanic lithosphere is destroyed when it subducts or dives beneath adjacent plates at subduction zones.
Are new oceanic lithosphere is unable to form at mid-ocean ridges?
New oceanic lithosphere is unable to form at mid-ocean ridges. Bands of magnetic material in the sea floor that have opposite poles, or exhibit magnetic reversal, can provide evidence for sea floor spreading.
Why does the oceanic crust sink beneath the continental crust at the subduction zone?
Oceanic crust is denser than continental crust that is why the former sinks through the process of subduction.
When an oceanic crust converges with another oceanic crust A?
When two oceanic plates converge, the denser plate will end up sinking below the less dense plate, leading to the formation of an oceanic subduction zone.
What is the difference between oceanic volcanism and subduction zone volcanism?
(2) How is the shape of volcanoes at mid-ocean ridges different from the shape of volcanoes at subduction zones? Mid-ocean ridge volcanoes tend to be linear and look like long, low ridges, while volca- noes at subduction zones tend to be cone- shaped and isolated.
Why does oceanic crust far from a mid-ocean ridge subside?
As the sheets of oceanic crust move away from the mid-ocean ridge, the rock is cooled and thus becomes heavier. After about 200 million years, the cooled lithospheric plate has become heavier than the asthenosphere that it rides over, and it sinks, thereby producing a subduction zone.
Why does the lithosphere thicken as it moves away from a mid-ocean ridge?
The oceanic lithosphere thickens as it ages and moves away from the mid-ocean ridge. This thickening occurs by conductive cooling, which converts hot asthenosphere into the lithospheric mantle, and causes the oceanic lithosphere to become increasingly dense with age.
What is the process by which new oceanic lithosphere is formed?
Sea-floor spreading is the process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies.
What hardens to form new rock at mid-ocean ridges?
Mid-ocean ridges are the boundaries between tectonic plates and are the place where the plates spread apart from each other. Magma from the underlying mantle erupts at the edges, then cools and solidifies to form new ocean crust.