mineral or not? which of these is a mineral? why or why not? rose quartz princess penny garnet gene...
TRANSCRIPT
Mineral or not?Which of these is a mineral? Why
or why not?
Rose Quartz
Princess Penny
Garnet
Gene Simmons
Eggs are to cake…Eggs are to cake…What minerals are to rocks.
3 Main Rock Groups
IgneousSedimentaryMetamorphic
Igneous Rocks
Igneous RocksIgneous comes from the Greek word for Fire.
Igneous rocks are formed when hot molten rock crystallizes and solidifies.
Igneous RocksForms from molten material
◦magma
Magma is molten rock
What is magma?
Magma is molten rock
What is magma?
Mostly oxygen, silicon, aluminum, iron, magnesium, calcium, sodium, potassium, titanium, and manganese.◦As well as melted rock, crystals, bits
of unmelted parent rock and dissolved gases.
Igneous Rocks
If magma cools quickly:◦There is less time for crystals to formCrystals will be small
Igneous Rocks
If magma cools slowly:◦There is more time for crystals to grow
Crystals will be larger
2 Types of Igneous Rocks
Based on where they form:
◦ Intrusive / Plutonic Magma that cools and hardens
below the surface.◦ Extrusive Magma that cools and hardens
above the surface (lava).
Intrusive Igneous Rocks Intrusive or Plutonic rocks form when
molten rock, or magma, is trapped deep within the earth where it slowly cools and solidifies.
The cooling may take thousands or even millions of years.
Since it takes so long to cool, the crystals within the rock may grow relatively large.
Slow cooling, and large crystals create a coarse grained texture.◦ Ex: granite, gabbro, diorite
Igneous RocksIntrusive or Plutonic
Batholith- large igneous intrusionSills – an igneous intrusion parallel to the layers
Lacolith – an igneous intrusion into sedimentary layers
Intrusive Igneous Rocks
Extrusive Igneous RocksExtrusive rocks are formed by
magma that exits the earth(lava).◦Ex: From volcanoes, and fissures.
As magma erupts from the earth it cools very rapidly. There is little time to form large crystals.◦Extrusive rocks are fine grained or
even glassy texture. Ex: basalt, rhyolite, obsidian.
Extrusive Igneous Rocks
Igneous Rocks
Igneous Rock groups2 main groups based on their
chemical composition;MaficFelsic
MaficMafic magmas have relatively low silica (Si) and high Fe and Mg contents.
◦The high Fe and Mg content makes these rocks heavier & darker than felsic types. Mafic magma will cool and crystallize to
produce the volcanic rock basalt and gabbro.
MaficVery Hot lava, rich in iron and
magnesium, low in silica, is fluid and flows like hot tar (highly viscous).◦ Mafic Magnesium
+ Iron Mg + Fe
Mafic rocksMagnesium + Iron (Fe)More easily weathered than
felsic-typesHighly dense/heavyDark colored
◦Ex: basalt, gabbro
Felsic Felsic magmas, have relatively high silica and low Fe and Mg contents.
◦Lighter in weight and color than mafic.
◦Felsic magma will cool and crystallize to produce dacite and rhyolite. Intermediate-composition magmas
will crystallize to produce the rock andesite.
Felsic
Cooler, gas-poor lava high in silicon, sodium, and potassium can be either pasty, blocky or flows very slowly (not viscous).◦ Felsic Feldspar +
Silicon Fe + Si
Felsic RocksFeldspar + Si
◦Harder◦Weather last◦Low density◦Lighter color◦Ex: quartz, muscovite, orthoclase
Igneous RocksIf lava is felsic and contains a
high percentage of gases it will be explosive.◦If thick the lava will explode in blocks
or bombs.
Igneous RocksIf lavas are thin and contain few
gases, the flow will be very viscous.◦Smooth, liquidy
How Igneous Rocks are formed
Extrusive Igneous Rocks
What type of igneous rocks are formed here?
http://hvo.wr.usgs.gov/gallery/kilauea/volcanomovies/
What types of igneous rocks would be formed here?