Structure of earth (layers of earth) Flashcards
(37 cards)
how many layers does the earth have? And what are those
3 - the core, the mantle, the crust
What are the outer most layers of earth?
The crust
____ is the lease dense layer of earth with thickness about 5-70 km
The crust
The crust is composed of solid ____ and ____ .
solid rock and minerals
______ is thickest at the tallest mountain ranges, and thinnest at the deepest ocean trenches.
the crust
How many part that the crust divide into and what are those?
(2)
1. the continental crust
2. the oceanic crust
the continental crust is composed mainly with of ____.
granite
the continental crust is sometimes called ___?
SIAL
why do the continental crust got called SIAL?
because its rock are rich in silicate and aluminum minerals.
the ___ crust is below the ocean.
the oceanic crust.
the oceanic crust is sometimes called?
SIMA
The oceanic crust is composed mainly of ____
basalt
why the oceanic crust got called SIMA?
because its rocks are rich in silicate and magnesium minerals.
the ____ is the layer below the crust.
the mantle
the mantle is _,___ km thick.
2900 km thick
The mantle is composed mainly of ____? (3)
silicon, magnesium and iron.
how many layers that the mantle have? and what are those?
(2)
1. the upper mantle
2. the lower mantle
the upper mantle is about ____ km thick
400 km thick.
the bottom part of the upper mantle form what?
asthenosphere
the upper mantle is divide into how many part and what are those?
(2)
1.top part of the upper mantle
2.the bottom part of the upper mantle
asthenosphere is composed of what?
semisolid or molten rock
called magma
why do magma in the asthenosphere flows?
it flows because it is under high pressure.
the lower mantle is about ______ km thick
2,500 km thick
the temperature of the lower mantle range is between
2,500-4,000 due to the high temperature and high pressure