What percentage of total area of lithosphere has the expansion of mountains?
Answers
Answer:
Theory of Plate Tectonics
STRUCTURE OF EARTH
The earth consists of three layers: an inner and outer core, the mantle, and two types of crust. The earth's core consists of two parts: a liquid outer core and a solid inner core, both made of iron and nickel from the early make-up of the planet, and where the temperatures can range from 8,600 degrees to 9,600 degrees Fahrenheit. The next and largest layer is called the mantle, which makes up two-thirds of Earth's mass. The mantle is actually called a plastic solid, which means it has the ability to flow very slowly. Heat from the earth's core causes the mantle to convect, like water over a stove but much slower, and it is the mantle's convection that is the driving force of plate tectonics.
The surface layer of the earth is called the crust and it makes up only 1 percent of Earth's mass. The crust is subdivided into two components: oceanic and continental crust. Again referring back to the image on the right, note that the oceanic crust is only about 3 miles thick, but is slightly more dense than continental crust. Most of this oceanic rock is called basalt and is a dark, dense rock. Continental crust is much thicker than oceanic crust (averages between 20 to 25 miles thick), but is actually slightly less dense than oceanic crust. The main type of rock on continents is called granite. So if these two types of crust were to collide into each other, what do you think would happen to the oceanic crust? As a whole, notice that the crust is lighter than the mantle. It is sometimes said that the crust "floats" on the mantle like an iceberg in water and that is not too far from the truth and is called isostacy. Finally, the crust is the coldest, most rigid, and brittle layer with lots of folds and fractures.
THEORY OF PLATE TECTONICS
The driving force of earthquakes and volcanoes is described in the theory of plate tectonics. The theory states that the earth is made of several tectonic plates along with several smaller plates. Each tectonic plate consists of oceanic and continental crust that move around the earth's surface like bumper cars because of convection within the mantle.
The theory also explains that the majority of earth's earthquakes and volcanoes occur along the boundaries of these tectonic plates as they either grind past or underneath each other.
There are three major types of tectonic plate boundaries: convergent, divergent, and transform. Let's first look at convergent plate boundaries, which can be broken down into three subcategories.
Recall that oceanic crust is denser than continental rock like granite. Thus when two tectonic plates collide, the denser oceanic crust will subduct underneath the lighter continental crust. If the subducting rock becomes stuck, vast amounts of energy builds up. But once the pressure and energy is too great, the rock will rupture creating powerful earthquakes. As the subducted material sinks further, it will begin to melt under great heat and pressure, becoming less dense as it melts, and rise up as magma to form dangerous composite volcanoes. Mountain ranges created by oceanic-to-continental convergence are the Andes mountains in South America, the Cascades in the western United States, and the Ring of Fire in the Pacific Ocean.
Below is a Google Earth image showing a series of oceanic-to-oceanic subduction zones within the Pacific Ring of Fire. You can visibly see the subduciton zones that create the volcanic and powerful Aleutian Islands and the converging subduction plates that make of volcanic islands of Japan.
With oceanic-to-oceanic convergence, the heavier of the two will subduct down beneath the other. Just like continental-to-oceanic convergence, this plate boundary can generate powerful earthquakes and volcanoes; but instead of volcanoes on land, volcanic islands form such as Japan, the Aleutian Islands of Alaska, and Indonesia. The great earthquake in Indonesia in 2004, which produced the devastating tsunami, was created by this process along with the 2011 earthquake and tsunami in Japan.
Answer:
Around 26-27% of the total area of lithosphere has the expansion of mountains.
Explanation:
Lithosphere:-
- Each rough planet has a lithosphere, yet what is lithosphere? It is the unbending furthest shell of an earth. Here on Earth the lithosphere contains the outside and upper mantle. The Earth has two kinds of lithosphere: maritime and mainland. The lithosphere is separated into structural plates.
- Maritime lithosphere comprises for the most part of mafic(rich in magnesium and iron) hull and ultramafic(over 90% mafic) mantle and is denser than mainland lithosphere. It thickens as it ages and moves from the mid-sea edge. This thickening happens by conductive cooling, which changes over hot asthenosphere into lithospheric mantle. It was less thick than the asthenosphere for a huge number of years, yet after this turns out to be progressively denser.
- The gravitational flimsiness of develop maritime lithosphere has the impact that when structural plates meet up, maritime lithosphere constantly sinks underneath the superseding lithosphere. New maritime lithosphere is continually being created at mid-sea edges and is reused back to the mantle at subduction zones, so maritime lithosphere is a lot more youthful than its mainland partner.
- The most established maritime lithosphere is around 170 million years of age contrasted with parts of the mainland lithosphere which are billions of years old.