TERM 4 - Geology Flashcards
What are the silica ranges called?
Felsic, Intermediate, Mafic and Ultramafic
What percentage of silica content does a rock have if it’s called a felsic rock?
> 65%
What percentage of silica content does a rock have if it’s called an intermediate rock?
55 - 65%
What percentage of silica content does a rock have if it’s called a mafic rock?
45 - 55%
What percentage of silica content does a rock have if it’s called an ultramafic rock?
< 45%
What does coarse-grained mean?
That crystals are visible to the naked eye.
What does fine-grained mean?
That the crystals aren’t visible to the naked eye.
What does clastic mean when describing a sedimentary rock?
That that sedimentary rock is made of clasts, or pieces of rock from other rocks.
What does chemical mean when describing a sedimentary rock?
It means the process where solvents, such as water, dissolve a solute and the solution made eventually takes too much solute. Particles of the solute eventually settle at the bottom to create sedimentary rock.
What are the stages of the forming of sedimentary rocks?
Weathering, Transportation, Deposition and Lithification
What is weathering?
Weathering is where rocks are degraded.
What is transportation (in terms of sedimentary rock formation)?
Transportation is where a fluid transports the weathered rock parts off to somewhere.
What is deposition?
Deposition is the settling of sediments.
What is lithification?
The compaction and cementation of sediments, creating a sedimentary rock.
What is volcanic ore?
Ore formed by the cooling of magma.
