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3. The geosphere
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3.4.
The rock cycle
Any rock can be transformed into a different type of rock.
These processes occur very slowly, so the rock cycle takes place over millions of
years.
Key concepts
❚
Rocks are aggregates of two
or more minerals.
❚
Accordingtotheirorigin,rocks
are classified into igneous or
magmatic, sedimentary, and
metamorphic.
❚
The process by which rocks
transform into different rocks
is called the rock cycle.
The
rock cycle
is a series of processes that a rock goes through to transform
into another type of rock.
The rock cycle
Understand
25.
Listen, look at the rock cycle and say true or false.
26.
In which layer of the geosphere does the rock cycle take place? Which
rocks form at the deepest level?
Analyse
27.
Explain which types of rocks can transform into igneous rocks.
All rocks, exposed to the action of wind and water, can go undergo the processes
of erosion, transportation and sedimentation. Sediments deposited in sedimentary
basins undergo the process of diagenesis or lithification and are transformed into
sedimentary rocks
.
The rocks in the Earth’s crust that are subjected to high pressures and/or temperatures
form
metamorphic rocks
. If the rocks melt, magma will form. Magma can rise and
cool under the crust, creating
plutonic igneous rocks
. Magma can also come out
of the crust to the exterior and solidify, creating
volcanic igneous rocks
.
