the scheme for igneous rock identification. a brief tour
TRANSCRIPT
The Scheme for The Scheme for Igneous Rock IdentificationIgneous Rock Identification
A Brief TourA Brief Tour
Crystal Crystal sizesize
DescriptionGrain Size
Igneous rocks have Igneous rocks have “Intergrown Crystals”“Intergrown Crystals”
IntergrownIntergrown
IntergrownIntergrown
IntergrownIntergrown
Not IntergrownNot Intergrown
Where it was formedWhere it was formedOutside the volcano: ExtrusiveInside the Earth: Intrusive
BubblesBubbles?? Yes= Vesicular
BubblesBubbles?? No=Non-vesicular
ColorColorVery Light
LightNotVery LightNot Very Dark
DarkVery Dark
Neither Light nor Dark
Ligh
test
Darke
st
DensityDensityVery Light
Light DenseVery Dense
Medium Density
Finding The MineralsFinding The MineralsIdentify the rock.Unless you have other information,
work in the middle of the rock’s box.
This is the amount of Potassium Feldspar in the rock.
This is the amount of Quartz in the rock.
This is the amount of Plagioclase Feldspar in the rock.
Use tick marks on a scrap paper to measure the percentage.Potassium Feldspar 25%
Quartz 40%
PracticePracticeName a light-colored, fine-grainedrock with no bubbles.
Name a coarse-grained, dense rock.
Name a very light-colored, glassy, extrusive rock with bubbles.