A metallic mineral with a strong red/brown streak color.
What is hematite?
What is a sedimentary rock?
A rock formed from sediments or solutes that are transported, deposited and then lithified by the combined effects of compaction and cementation.
Formed from the cooling of magma (intrusive) or lava (extrusive).
What is an igneous rock?
A pre-existing rock that was deformed by immense pressure and/or heat without the rock melting (doesn't return to magma). Metamorphic rocks can be made from igneous, sedimentary or other metamorphic rocks.
What is a metamorphic rock?
What is cleavage in a mineral? How is this different than fracturing?
The tendency of a mineral to break along smooth planes parallel to zones of weak bonding.
If a mineral fractures it has no planes of cleavage. It will break irregularly.
A mineral that fractures is quartz.
Term used to describe a mineral with a "glassy" look to it. (i.e. quartz, fluorite)
What is vitreous luster?
Way to describe grain shape of arkose.
What is angular grain angularity?
A phaneritic rock which contains quartz, biotite and potassium feldspar.
What is granite?
Marble and quartzite share this characteristic.
Non-foliated metamorphic rocks
What is the difference between how intrusive and extrusive rocks form? How does this affect the texture of the rocks?
Intrusive: formed within earths crust from slow cooling of magma.
Extrusive: formed at earths surface from rapid cooling of lava.
Intrusively formed rocks are phaneritic. Extrusively formed rocks are mainly aphanitic.
Muscovite, biotite, and gypsum share this property.
What is single perfect cleavage?
Depositional environment shared by sandstone and conglomerate.
What are rivers?
This rock is felsic, vesicular and extrusively formed.
What is pumice?
Name three of the four foliated rocks from class.
(Can you name the fourth?)
Gneiss
Schist
Phyllite
Slate
Describe foliation and how it occurs.
A sheet like, layered structure in rocks. Caused by shearing forces or differential pressure.
One mineral reacts with HCl only when powdered, the other will react with HCl even when it is not powdered.
What is the major difference between dolomite and calcite?
Rock with grains that are clay-sized, well-sorted and well-rounded.
What is shale/mudstone?
How do porphyritic rocks form? Give examples of porphyritic rocks.
Two stage formation. First stage, the magma is cooled slowly deep in the crust, creating the large crystal grains. Second stage, the magma is cooled rapidly at relatively shallow depth or as it erupts from a volcano, creating small grains.
Examples: Rhyolite, Andesite
Name the protolith(s) of marble, quartzite, and hornfels
Marble: limestone or dolomite
Quartzite: Sandstone
Hornfels: Pretty much and rock (igneous, sedimentary, and metamorphic)
Mineral that is harder than glass, has no cleavage or streak color and a green bulk color. It may have vitreous luster or a sandy grain texture.
What is olivine?
What is the difference in depositional environment between fossiliferous limestone and crystalline limestone?
There is none. Both form in marine environments.
Igneous rock that exhibits a combination of intrusive and extrusive characteristics.
What is Andesite?
Fill in the blanks
Answer:
1: Shale
2: Slate
3: Phyllite
4: Schist
5: Gneiss
6: Increasing Metamorphism