p.24 Rock Cycle and Igneous Petrology
rock cycle t igneous pet ro lo g y
Lt what are the properties of igneous rocks and how do I identify them
the rock cycle is a never ending process of how the earths
matter moves through the crust
minerals aremade up of elementsfrom the periodictable
rocks are made up of minerals
igneousrocks are formed by thecooling andcrystallizingof
hot lava or magma
two types of moltenrock
lava not molten rock on the surface of earth
magma hot molten rock beneaththesurface of earth
grainsize is howbigor small an individualgraincrystal is
within a rock these will be theminerals that make up the
rock look for colors
typesofgrains
microscopic cannot see with yournaked eye includes
glassy vesicular glassylooking
fine about the size of a sand partial
coarse larger than sand size particles 2mm
locations
intrusive formed cooled inside of the earth corse grains
extrusive formed cooled outside of the earth fine to
microscopicgrains
magma rockcolors
lightcolored white pink clear tan grey and black
mediumcolored white grey green tan and black
dark colored dark grey green and black
light colored magmatype felsic
minerals within quartzfeldspars both micas both
hornblend
rock names pumicerhyolitegranite
medium colored magmatype andesitic
mineralswithin plagioclasefeldspar biotite mica hornblende
rock names obsidian andesite diorite
dark colored magmatype mafic
mineralswithin plagioclase feldspar olivine biotite
mica hornblende usually a lot
rock names scoria basalt gabbro
Igneous Rocks
Weathering
toooc e
fcompact and
i i
i imelting
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