chemical composition - silica (SiO2) content Flashcards by obi ajayi | Brainscape

Q

what is silica content in rocks used for

A

distinguish igneous rocks into subdivisions

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

silica content subdivisions of rocks

A

ultrabasic (ultramafic) (least SiO2)

basic (mafic)

intermediate

acid (felsic) (most SiO2)

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

basic mafic rocks characteristics

A

lower SiO2 content than felsic, <52wt%

darker rocks in colour

minimal quartz

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

basic felsic rocks characteristics

A

higher SiO2 content than mafic, >52wt%

lighter rocks in colour

most quartz and feldspar

How well did you know this?

1

Not at all

2

3

4

5

Perfectly

Q

TAS diagram

A

total alkali vs silica diagram

used for volcanic rocks

diagram on phone

How well did you know this?

1

Not at all

2

3

4

5

Perfectly