1/7
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced | Call with Kai |
|---|
No study sessions yet.
Igneous rocks
Igneous rocks comes from the cooling of magma that results in any crystalline or glass rock
Extrusive igneous formed by cooling on the surface of the earth
Intrusive igneous formed by cooling of magma within the earths crust.
Types of magma
Basaltic: high in iron, magnesium, calcium. Low in sodium and potassium
Andesitic: intermediate in all elements listed above
Rhyolitic: low in iron, magnesium and calcium. High in sodium and potassium.
Textures of igneous
Common fold with crystal nucleation and growth
Can have a glassy look ( obsidian)
Sedimentary rocks
70% of earths rocks are sedimentary in origin
Once deposited sediments undergo diagenesis
Diagenesis involves physical, chemical and/or biological processes which bring about compaction, cementation, recrystallisation and/or other modifications to an original sediment
Categories of sedimentary rocks
Siliciclastic - consists of fragments or clasts of pre existing rock transported by physical processes
Organic sediments
Chemical sediments
Volcaniclastic - lava and rock fragments derived from volcanic activity.
Metamorphic rocks
Process of change where original rock recrystallises in new conditions to produce a new type of rock that contains new minerals.
Types of metamorphic change
Phase change - replacement of original minerals with new metamorphic minerals as a result of a chemical reaction
Textural changes - recrystallisation to produce new minerals
ALL METAMORPHISM OCCURS IN A SOLID STATE OTHERWISE IT WOULD BECOME IGNEOUS ROCK AGAIN