Term
|
Definition
Ash
Fragmental(clastic)
Unlithified pyroclastic fragments having a grain size of less than 2.0mm |
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Term
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Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
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Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
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Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
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Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
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Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
|
Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
|
Definition
Granite
Crystalline
Phaneritic
Contains Quartz and Orthoclase
Only granite and rhyolite can have pink orthoclase |
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Term
|
Definition
Lapillistone
Fragmental (clastic)
Lithified
2.0-64.0 mm
Note: The things in the rock have no geometry. |
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Term
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Definition
Lapilli
Fragmental (clastic)
Unlithified
2.0-64.0 mm
Note: The finer grain component is ash |
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Term
|
Definition
Basalt
Aphanitic
porphyritic
Olivine Phenocrysts
Note: Olivine phenocrysts usually have no geometry |
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Term
|
Definition
Basalt
Aphanitic
porphyritic
Olivine Phenocrysts
Note: Olivine phenocrysts usually have no geometry |
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Term
|
Definition
Basalt
Aphanitic
porphyritic
Olivine Phenocrysts
Note: Olivine phenocrysts usually have no geometry |
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Term
|
Definition
Mafite
No visible olivine
aphanitic
non-porphyritic
dark |
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Term
|
Definition
Mafite
No visible olivine
aphanitic
non-porphyritic
dark |
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Term
|
Definition
Mafite
No visible olivine
aphanitic
non-porphyritic
dark |
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Term
|
Definition
Mafite/Basalt
If Mafite:
No visible olivine
aphanitic
non-porphyritic
dark
If Basalt:
Aphanitic
porphyritic
Olivine Phenocrysts
Note: Olivine phenocrysts usually have no geometry |
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Term
|
Definition
Pyroxenite
Phaneritic (coarse grained)
No quartz
>80% Dark
greenish black color suspects augite or horneblende
cleavage-2d at right angles |
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Term
|
Definition
Pyroxenite
Phaneritic (coarse grained)
No quartz
>80% Dark
greenish black color suspects augite or horneblende
cleavage-2d at right angles |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Andesite
Aphanitic (fine grained)
prophyritic
If dark crystals
dark crystals (horneblende)
Note: phenocrysts have geometry; not only do they exhibir crystal faces, cleavage surfaces are also obvious.
If light crystals:
light crystals (plagioclase)
Note: phenocrysts have geometry, like little shoeboxes. Some crystals have cleavage. |
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Term
|
Definition
Horneblendite
Phaneritic
>80% Dark
>50% Horneblende
Shiny black cleavage
2-d not at right angles |
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Term
|
Definition
Horneblendite
Phaneritic
>80% Dark
>50% Horneblende
Shiny black cleavage
2-d not at right angles |
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Term
|
Definition
Horneblendite
Phaneritic
>80% Dark
>50% Horneblende
Shiny black cleavage
2-d not at right angles |
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Term
|
Definition
Horneblendite
Phaneritic
>80% Dark
>50% Horneblende
Shiny black cleavage
2-d not at right angles |
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Term
|
Definition
Horneblendite
Phaneritic
>80% Dark
>50% Horneblende
Shiny black cleavage
2-d not at right angles |
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Term
|
Definition
Diorite
Crystalline
phaneritic
50-80% dark
No Quartz |
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Term
|
Definition
Diorite
Crystalline
phaneritic
50-80% dark
No Quartz |
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Term
|
Definition
Scoria
High Vesicular >50%
glassy
usually reddish
does not float |
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Term
|
Definition
Scoria
High Vesicular >50%
glassy
usually reddish
does not float |
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Term
|
Definition
Scoria
High Vesicular >50%
glassy
usually reddish
does not float |
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Term
|
Definition
Gabbro
crystalline
phaneritic
no quartz
>80% dark
>50% plagioclase
look for striations or bluish irridescence |
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Term
|
Definition
Gabbro
crystalline
phaneritic
no quartz
>80% dark
>50% plagioclase
look for striations or bluish irridescence |
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Term
|
Definition
Gabbro
crystalline
phaneritic
no quartz
>80% dark
>50% plagioclase
look for striations or bluish irridescence |
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Term
|
Definition
Gabbro
crystalline
phaneritic
no quartz
>80% dark
>50% plagioclase
look for striations or bluish irridescence |
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Term
|
Definition
Obsidian
glassy - looks like glass
non-vesicular
conchoidal fracture |
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Term
|
Definition
Obsidian
glassy - looks like glass
non-vesicular
conchoidal fracture |
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Term
|
Definition
Obsidian
glassy - looks like glass
non-vesicular
conchoidal fracture |
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Term
|
Definition
Obsidian
glassy - looks like glass
non-vesicular
conchoidal fracture |
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Term
|
Definition
Rhyolite
crystalline
aphanitic
porphyritic
quartz phenocrysts
Note: use microscope - quartz crystals usually have no geometry but are easy to identify. |
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Term
|
Definition
Rhyolite
crystalline
aphanitic
porphyritic
quartz phenocrysts
Note: use microscope - quartz crystals usually have no geometry but are easy to identify. |
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Term
|
Definition
Rhyolite
crystalline
aphanitic
porphyritic
quartz phenocrysts
Note: use microscope - quartz crystals usually have no geometry but are easy to identify. |
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Term
|
Definition
Pumice
Low Density
Will Float
>50% vesicular
usually whitish |
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Term
|
Definition
Pumice
Low Density
Will Float
>50% vesicular
usually whitish |
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Term
|
Definition
Pumice
Low Density
Will Float
>50% vesicular
usually whitish |
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Term
|
Definition
Pumice/Lapilli
Lapilli sized Pumice grains
Low Density
Will Float
>50% vesicular
usually whitish |
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Term
|
Definition
Pumice/Lapilli
Lapilli sized Pumice grains
Low Density
Will Float
>50% vesicular
usually whitish |
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Term
|
Definition
Pumice/Lapilli
Lapilli sized Pumice grains
Low Density
Will Float
>50% vesicular
usually whitish |
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Term
|
Definition
Tuff
fragmental
lithified (is formed into a rock)
grain size less than 2.0mm |
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Term
|
Definition
Tuff
fragmental
lithified (is formed into a rock)
grain size less than 2.0mm |
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Term
|
Definition
Tuff
fragmental
lithified (is formed into a rock)
grain size less than 2.0mm |
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Term
|
Definition
Granodiorite
crystalline
phaneritic
has quartz in it
<50% dark |
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Term
|
Definition
Dunite
crystalline
phaneritic
no quartz
>80% dark
>50% olivine |
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Term
|
Definition
Dunite
crystalline
phaneritic
no quartz
>80% dark
>50% olivine |
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