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What do the terms mean?
cyrstals too small to see easily without a magnifying glass
formed from living organisms (shells) settling out of water
material forming directly out of dissolved materials in water (like making rock candy)
Clastic or detrital
formed from materials settling out of water
formed from wind sediments
form outside of the earth's crust or just barely under- cooling rapidly
refers to sedimentary rocks that easily split into layers (shales)
formed in river beds
appears to be layers of crystalline rock- term used for metamorphic rocks only
formed inside of the earths crust, plutons are intrusive, cool slowly
formed in lakes
high in ferromagnesium silicates (olivine, biotite, hornblend)
having easily visible crystals
rock formed from magma that penetrated other rocks- dikes, sills, batholiths
high in non-ferromagnesium silicates (feldspars, muscovite, quartz)
has vesicles (holes) which are apparent