Characterizing Rocks

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A Rock

An aggregate of 1 or more mineral/mineral materials

Igneous Rock, formed by magma

Classified by where they form and chemical composition

Glassy

Volcanic Rock, cools slowly

Extrusive Aphanitic

No visible mineral crystals, cooled quick on the surface

Intrusive Phaneritic

Visible mineral crystals, cooled slowly underground

Porphyritic Rock

Both visible and non-visible mineral crystals, multiple cooling events

Mafic

Contains lots of magnesium and iron, formed by hot magma

Felsic

Contains lots of silica, formed by cooler mamga

Intermediate

In the middle

Clastic Sedimentary Rock

Made up of rock pieces that have been cemented together, classified by grain size

Mud Rock

Clastic Sedimentary smallest grain size

Sand Stone

Clastic Sedimentary medium grain size

Conglomerate Rock

Clastic Sedimentary biggest grains size

Non Clastic Sedimentary Rock

Either formed from living things or chemical precip

Metamorphic Rock

Heat and pressure to transform Igneous/Sedimentary rocks

Meatmorphic Rock Traits

Smearing and Foliation

Foliated Metamorphic Rock

Differential pressure on sides causes minerals to form in layers

Non Foliated Metamorphic Rock

Equal pressure on all sides, no layers