GEO - Chapter 2 Flashcards
How is igneous rock formed
- the cooling and solidification of magma orlava.
How is sedimentary rock formed
- the accumulation and lithification of sediment
What is Lithification
- the process by which sediments come together to form sedimentary rock
What are the 3 types lithification can occur
- Compaction
- Cementation
- Recrystallization
What is Compaction
- sediments are pressed together due to pressure
What is Cementation
- dissolved minerals in the water undergo crystallisation
What is Recrystallization
- minerals in sediments are exposed to water and the crystals change their structure
How is metamorphic rock formed
- exposure to heat and pressure
What trend causes volcanic igneous rocks to have smaller crystal size to plutonic igneous rocks
As the speed of cooling of melted rock is increased, size of crystals is decreased.
What is the difference between lava and magma cooling times
lava cools rapidly while magma cools slowly
How is lava different to magma
lava is magma that has been errupted and exposed to outside conditions.
What are plutonic igneous rocks in formed from
magma
What are volcanic igneous rocks formed from
lava
Do plutonic or volcanic igneous rocks have larger crystals and WHY?
plutonic igneous rocks have larger crystals
- because of the slower cooling time of magma
What are the 3 types of sedimentary rock
clastic
chemical
biological
How is Clastic sedimentary rock formed
sediments of pre-existing rocks and minerals undergo lithification
How is Chemical sedimentary rock formed
water traveling through rocks dissolves minerals which are carried away and are re-deposited when the water evaporates
How is Biological sedimentary rock formed
living organisms die, pile up, and undergo
How are contact metamorphic rocks formed?
Magma comes in contact with surrounding rock - changing via the high temperature
How are regional metamorphic rocks formed?
High temperature and pressure at deep subduction zones in the earth’s crust
What are the 2 types of weathering?
Mechanical weathering
Chemical weathering
What 4 things cause mechanical weathering?
- temperature change
- frost action
- roots growing into rock
- animal activity
What are the 3 things that cause chemical weathering?
- oxygen
- rainwater
- carbon dioxide
What does heat and pressure form
Metamorphic rock
What does weathering and erosion form
Sediment
What does cooling of magma or lava form
Igneous rock
What does melting form
Magma
What does compaction and cementation form
Sedimentary rock
What rock types can be eroded
All rocks :)
