not a true mineral

has more than one minerals cleavage plane

has no mineral cleavage

is a common mineral

identical to the original chemistry of the source rock that was partially melted

more mafic than the original chemistry of the source rock that was partially melted

completely unpredictable (it could be more mafic or more felsic)

more felsic than the original chemistry of the source rock that was partially melted

Mountainous landscape with higher energy

Aeolian environment which wind is the dominant agent of sediment transport

Lake environment with low energy

Delta with low to moderate energy and far from the source location.

Contact Metamorphism

Subduction zone metamorphism 

Regional Metamorphism 

Fault metamorphism 

Quartz rich sandstone when metamorphosed forms non-foliated quartzite.

Banded gneiss is a high-grade foliated rock which the protolith can be one of several different rocks.

A schist is formed from the metamorphism of shale and has no foliation.

Marble is non-foliated and formed from metamorphism of limestone.

Magma differentiation 

Flux melting

Heat-transfer melting

Decompression melting

the metamorphic grade is increasing 

the formation of mafic and felsic intrusions

the progression of mafic to felsic igneous rock formation 

the grades of non-foliated metamorphic fabric

Lineation

Foliation

Schistosity

Non-foliation

compaction and diagenesis

recrystallization and compaction

burial and diagenesis

cementation and compaction

The structures within the sandstone beds are faults indicating the sands were deposited during a period of high seismic activity.

These features were formed by wind or water.

The cross-beds structures indicate a flow direction.

The reddish color that is the result of oxidation of iron-bearing minerals indicates the sand was deposited on land and exposed to air.