How is new oceanic lithosphere formed?
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..
What is oceanic lithosphere made of?
Oceanic lithosphere consists mainly of mafic crust and ultramafic mantle (peridotite) and is denser than continental lithosphere. Young oceanic lithosphere, found at mid-ocean ridges, is no thicker than the crust, but oceanic lithosphere thickens as it ages and moves away from the mid-ocean ridge.
At which type of plate boundary is new oceanic lithosphere formed?
divergentAs plates move away from each other the lithosphere thins and tears. At these divergent plate boundaries new oceanic lithosphere is created in the gaps from upwelling magma from the mantle. This upwelling magma forms mid-ocean ridges, long mountain chains that mark the boundaries between diverging plates.
Where does the lithosphere come from?
The word lithosphere is derived from the word “sphere,” combined with the Greek word “lithos” which means rock. The lithosphere is the solid outer section of Earth which includes Earth’s crust (the outermost layer of rock on Earth), as well as the underlying cool, dense, and fairly rigid upper part of the upper mantle.
What are the 2 types of crust?
Earth’s crust is divided into two types: oceanic crust and continental crust. The transition zone between these two types of crust is sometimes called the Conrad discontinuity. Silicates (mostly compounds made of silicon and oxygen) are the most abundant rocks and minerals in both oceanic and continental crust.
What color is the lithosphere?
There are several layers shown, color coded brown and black, green, and reddish. The outermost brown and black layer, above the Moho (boundary between crust and mantle) is the crust….LSF Home | Geology Web Sites | Courses | JMU GeologyLast Update: 9/05/00e-mail: (Fichtels@jmu.edu)Sep 5, 2000