The crust and part of the upper mantle,
Make up the lithosphere.
The common rocks we see around us,
Most of it comes from the lithosphere.
There are many kinds of rocks,
According to different formation principles,
Rocks can be divided into three major groups:
Igneous, sedimentary and metamorphic rocks
The formation of igneous rocks,
It has to do with magma erupting,
Hence the name magmatic rock.
They are all formed when magma cools and crystallizes
More magma erupts from the earth's interior,
Only a small amount of magma is ejected from the surface.
If in volcanic activity,
Magma erupting from the surface,
In relatively cold air or water,
It cools quickly and crystallizes quickly (even before it does).
The igneous rock formed in this case,
Generally fine particles, sometimes with pores,
This igneous rock is called extrusive igneous rock,
Also called volcanic rock.
If the magma doesn't come out of the surface,
It's cooled below the surface,
So they cool down very slowly,
The longer the cooling time, the better the crystallization.
The volcanic rock formed under these conditions,
Generally the particles are relatively thick,
This igneous rock is called intrusive igneous rock.
According to the depth of formation, can also be divided into deep diagenesis, shallow diagenesis.
After the igneous rocks formed,
It doesn't stay the same forever.
They are likely to undergo physical and chemical changes,
They are then converted into sedimentary or metamorphic rocks.
Having been eroded by external forces,
They break down into sediments.
Sediment consists of rock fragments,
And the composition of sand, clay, and biological remains.
The sediment accumulates layer by layer,
The later one is on the top,
The first one is down here.
The sedimentary rocks buried in the depths are pressurized and warmed,
Turning loose sediment into solid rock,
Sedimentary rock was born.
There are rocks,
In addition to being able to undergo transport, sedimentation, and diagenesis,
Beyond the sedimentary rocks,
It can also be converted into metamorphic rock according to the surrounding temperature and pressure changes
Metamorphic rocks are formed mainly by changes in temperature and pressure.
As the temperature and pressure increase,
New minerals will form in the rock
This produces metamorphic rocks.
This is called metamorphism.