Because by actual measurement, the "crust" of the earth, in relation to the size of the earth, is just about as thick as the skin of the apple in relation to the rest of the apple.
the Continental crust is thicker
They form when the oceanic crust goes under the Continental crust. The oceanic crust then forms the trenches through a process called subduction.
Earth's crust is made of sedimentary, metamorphic, and igneous rock. The continental crust is composed primarily of granitic rock and can be up to 45 miles thick. The oceanic crust is composed primarily of basaltic rock and can be up to 6 miles thick.
When plates are actually coming towards each other, there can be two different boundaries: collision and destructive boundaries. In a collision boundary, there are earthquakes, and fold mountains are created from the plates pushing up against each other, like the Himalayas. When there is a destructive boundary, like the Eurasian and Pacific plates, the oceanic plate slides underneath the continental plate, being destroyed and causing earthquakes and volcanic eruptions. There are two other types of boundaries: conservative, where plates slide past each other, and constructive, where plates move away from each other.
Jupiter's moons - Europa and Ganymede possibly have oceans of liquid water under their crust. Saturn's moon - Enceladus also has a possible ocean of water under it's crust.
The Earth's crust is very thin compared to the rest of the planet, so on scaled drawings that include the entire Earth, the crust appears thin and barely visible relative to the size of the entire planet. Additionally, the scale used in drawings often emphasizes other geological features or layers, making the crust less prominent in the overall representation.
The crust of the Earth varies from 5-70 km thick which when compared to the total radius of the Earth (6,360 km) is very small, accounting for between 0.07 and 1.1% of Earth's total radius. To put that into context, if the Earth was the size of a football (soccer ball), the oceanic crust would be the same thickness as one human hair (70 micrometres).
Intrusive- Formed under the crust. Barley any Crystals. Extrusive- Formed out of the crust. More Crystals.
Well, as the name implies, visible areas of the crust are areas that you can see. These are areas that are either very new, resulting from recent vulcanism; or areas which have been exposed by weathering and erosion. Non-visible parts of the crust are just that - not visible to the eye. This is either because they have formed recently, but many miles underground; or they are just too old to have been efficiently exposed by weathering and erosion.
Oceanic crust is predominately made of basaltic rock with a thin layer of sedimentary rock on top. Continental crust is predominately made of granitic rock, with a thin layer of sedimentary rock covering much of the visible surface.
Their surface is often quenched by the sea water so often at the surface they are, crystals will grow and be visible deeper in the rock.
Oceanic crust:As the name already suggests, this crust is below the oceans. There, the crust is 4-7 miles (6-11 km) thick. The rocks of the oceanic crust are very young compared with the rocks of the continental crust. The rocks of the oceanic crust are not older than 200 million years. The material of which the oceanic crust consists is for the greater part tholeiitic basalt (this is basalt without olivine). Basalt has a dark, fine and gritty volcanic structure. It is formed out of very liquid lava, which cools off quickly. The grains are so small that they are only visible under a microscope. The average density of the oceanic crust is 3g/cm³.
If all the crust above sea level were removed, the Earth would essentially resemble a giant ocean planet with no landmasses visible. The entire surface would be covered by water, leading to a vast global ocean.
The Crust. the crust The crust!
The majority of Earth's surface is covered in a veneer of sedimentary rock, making them the most visible surface rock.
The active earth's core continually recycles itself through subduction zones located around certain parts of the planet. The subduction zones are where one tectonic plate is being forced under another, thereby recycling the old crust. New crust is made at rift zones where magma is forced to the surface, cools and then becomes part of our visible (or underwater) earth surface.
crust on a pizza (thin & thick) or the earth's crust