3IGNEOUS ROCKS are formed from cooled magma or lava We use COLOR & TEXTURE to classify the rocks
4The COLOR of a rock depends on the rock’s mineral content The type of mineral the rock is made up of determines how it is classified
5The rock may look light or dark LIGHT ROCKSThe rock may look light or darkHas “light” mineralsLIGHT MINERALS:QUARTZORTHOCLASE FELDSPAR
6The rock may look light or dark DARK ROCKSThe rock may look light or darkHas “dark” mineralsDARK MINERALS:AUGITEOLIVINE
7TEXTUREA rock’s TEXTURE is determined by the size of the mineral crystals within the rockIgneous Rocks have 3 basic textures
8COARSE-GRAINED FINE-GRAINED GLASSY Has crystals large enough to be seen with the naked eyeFINE-GRAINEDHas crystals that are too small to see with the naked eyeGLASSYCrystals are NOT visible.Glassy rocks can be smooth or full of bubble holes
9vocabulary Igneous rock Rock formed from cooled magma or lava Extrusive igneous RockIgneous rock that forms above the Earth’s surface from lavaIntrusive igneous rockIgneous rock that forms below the Earth’s surface from magma
12SEDIMENTARY ROCKSSEDIMENTARY ROCKS are formed from the compaction & cementation of sediments
13Pressure causes accumulated sediments to harden into rock. This process takes thousands of years.Sedimentary rocks are classified according to the material from which they formed.
14clastic: organic: chemical: Composed of different sized rock fragments compacted togetherorganic:Composed of the remains of dead plants & animals(may include shells, skeletons & other organic matter)chemical:Formed from minerals that were once dissolved in water(water evaporated & minerals became crystals)
15vocabulary Sedimentaryrock Rock made of sediments Sediment Compacts together to form sedimentary rock; created by erosioncompactionThe compressing of sediments into sedimentary rock
16erosionWearing away of soil, landforms & rock by wind, gravity, moving water & glacierslithificationCompaction & cementation into sedimentary rockweatheringThe breakdown of rocks by natural processes
19metamorphic ROCKSMETAMORPHIC ROCKS are formed from igneous or sedimentary rocks that undergo lots of heat & pressure over a long period of time
20This process takes thousands of years. Igneous & Sedimentary rocks deep beneath the Earth’s surface change (morph) into metamorphic rocks because of the high temperatures & great pressure of all the rock layers above.This process takes thousands of years.
21No visible layering or stripes 2 TEXTURE TYPESNON-FOLIATED:No visible layering or stripesFOLIATED:(BANDED)Minerals “line up” to give a striped/layered appearance
22vocabulary foliation Metamorphic Rock Mineral bands/layers in metamorphic rockMetamorphic RockRock formed from an igneous or sedimentary rock because of heat & pressure
27IGNEOUS ROCKS are formed from cooled magma or lava An intrusive igneous rock forms from magma. As it cools slowly inside the earth the minerals form large crystals.An extrusive igneous rock forms from lava on the surface. These rocks cool quickly and have tiny crystals.
28Weathering & erosion acts upon rocks to create sediments. SEDIMENTARY ROCKSSEDIMENTARY ROCKS are formed from the compaction & cementation of sedimentsWeathering & erosion acts upon rocks to create sediments.Over time layers of sediment compact & compress together to form sedimentary rock. This process is known as lithification.
29metamorphic ROCKSMETAMORPHIC ROCKS are formed from igneous or sedimentary rocks that undergo lots of heat & pressure over a long period of time, which causes the rock to change.
30Rock CYCLE:The combination of all the processes that act to break down rocks, move sediments, and produce new rocks.
345 processes of the rock cycle The combination of all the processes that act to break down rocks, move sediments, and produce new rocks.3 groups of rocksIgneous- Forms from cooled magma or lavaSedimentary- Made of sediments that compacted over timeMetamorphic- Forms due to heat & pressure5 processes of the rock cycleCooling of magma or lava forms igneous rockWeathering & Erosion of a rock forms sedimentsLithification of sediments forms sedimentary rockHeat & Pressure on a rock creates metamorphic rockMelting of a rock forms magma