Question

Define sial & sima

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Answer 1

Sima is the name for the lower layer of the Earth's crust. This layer is made of rocks rich in silicates and magnesium minerals. Typically the sima when it comes to the surface is basalt, so sometimes this layer is called the 'basalt layer' of the crust.


And


Sial is

Sial is the name for the upper layer of the Earth's crust, which is also known as the continental crust because it is absent in the wide oceanic basins. This layer is made of rocks rich in silicates and aluminium minerals.Sial runs between 5 km and 70 km deep.

Answer 2

sima is the name for the lowest layer of the earth's crust . this layer is made of rocks rich in magnesium silicate minerals . the sime layer is also called tha basal crustal or basal layer . the name sima was taken from the first two letters of silica and of magnesium. 
sial is the upper layer of earth's crust , namely rocks rich in silicates and aluminium minerals .the name sial was taken from the first two letters of silica and aluminium .the sial is the next lower layer in the earth .

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