Geology Flashcards
What are the layers of the earth
Crust
Mantle
Outer core
Inner core
What is lustre
How it reflects light
Streak
Powdery mark left from being scraped
Hardness
Determined by scratching minerals together
What is and extrustive rock
Extrusive rocks are formed from lava above the surface
What is an igneous rock
Formed from cooling magma below the earth crust or lava
What is an igneous rock formed under water
Extrusive
What factors how extrusive rocks look
How quickly they cool and what substances it contains
When lava cools quickly crystals are ….
Small
When lava cools slowly crystals are …
Big
How are air bubbles formed
When volcanoes shoot our lava filled with gas and the lava cools quickly mid air
Pumice
Pale coloured
Light as full of tiny holes
Can float on water
Scoria
Heavier than pumice
Dark as it contains iron
Reddish brown or grey
Basalt
Extrusive
Takes on many appearances
Basalt crystals can be different sizes
Obsidian
Smooth Black rock looks like glass Formed when lava cools almost instantly No crystals Sometimes very fine bubbles
Granite
Has large crystals
Very hard
What is a sedimentary rock
Rocks formed from particles of sediments
How are sediments deposited
When weathered rocks are moved due to rain, wind, ect.
Erosion
How are sand dunes formed
Sand deposited by wind
How is sandstone formed
From grains of sand that have been cemented together over a period of time.
How are mudstone and shale formed
Fro, finer grains of sediments that are deposited by calm water in the form of mud
Rocks can change in the surface due to
Weathering, cracking, bending and erosion
Rocks can change underground because of …
Due to heat and pressure
Metamorphism
Process of changing
