Flashcards
Geologic Igneous Rocks
Cards in this deck (28)
- 1Igneous RocksAre born of fire and look like they are made of interlocking crystals
- 2Forming CrystalsNeed high temperatures, high pressures, recrystallization, precipitation, organisms can create crystals and liquids freezing can create crystals
- 3Forming Igneous RocksDecompressions in the mantle form molten rock which cools and crystallizes to form igneous rocks
- 4EarthIs made of the inner core, outer core, mantle and crust
- 5Melting of Mantle RocksDecompression melting and flux melting
- 6Decompression MeltingWhen the pressure on rock is reduced and then it melts
- 7Flux MeltingWhen volatile compounds like water of gas and the rock melts
- 8Signs in Igneous RocksThe texture and composition
- 9TextureCan be phaneritic, pegmatitic, aphanitic, glassy, vesicular or porphyritic
- 10Phaneritic TextureCan see crystals easily
- 11Pegmatitic TextureReally coarse and big crystals
- 12Aphanitic TextureFine crystals, barely seen
- 13GlassyNo apparent crystals
- 14Vesicular TextureFrozen gas bubbles
- 15Porphyritic TextureSome large crystals in a fine crystal matrix
- 16Large CrystalsMeans that there was a slow cooling rate and therefore had a long time to cool, so we know it is intrusive or plutonic
- 17Small CrystalsMeans that there was a fast cooling rate and therefore had a short time to cool, so we know it is extrusive or volcanic
- 18Rate of CoolingDepends on groundwater presence, the size and shape of magma, and magma depth
- 19CompositionCan be felsic, intermediate or mafic and is determined using mainly colour
- 20Felsic CompositionIs a very light coloured rock like alkali feldspar or quartz
- 21Intermediate CompositionIs between felsic and mafic composition, can have a partially dark or light colour
- 22Mafic CompositionHas a very dark appearance like basalt
- 23ExtrusiveIgneous rock formed of material that has been ejected onto the Earth's surface
- 24IntrusiveIgneous rock formed of magma that crystallized in the crust or manlte
- 25PlutonicIgneous rock formed deep within the crust or mantle
- 26VolcanoesA landform that releases lava, gas, or ashes to the surface of the earth. Can form extrusive igneous rock when lava cools on the surface
- 27Magma DifferentiationWhen magma migrates through the crust and its composition changes
- 28Country RockThe rock in the crust that surrounds an igneous intrusion