Download - Minerals in granite
![Page 1: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/1.jpg)
Minerals in granite
The igneous rock granite is composed of manyseparate grains of several main minerals
Figure 2.1
![Page 2: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/2.jpg)
What is a mineral?
Naturally occurring solid
Specific chemical composition
Crystal structure(regularly repeating units
in 3 dimensions)
![Page 3: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/3.jpg)
Structure of halite
Mineral composed of Na Cl
Sodium Na+
Figure 2.2
Chloride Cl–
![Page 4: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/4.jpg)
What is a rock?
Naturally occurring solid aggregate
Made of one or more mineralsGranite, basalt, rock salt, limestone
Consolidated aggregate of rock particlesSandstone, shale
Solid mass of rock-like materialsCoal, obsidian (a volcanic glass)
![Page 5: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/5.jpg)
Electron shells of an atom
Nucleus is a small part of the total volume
Figure 2.3
Nucleus – made of protons and neutronsElectrons orbiting the nucleus
![Page 6: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/6.jpg)
Filling electron shells
First shell – 2 electrons
Helium
2nd shell – 8 electrons
NeonNoble
gases
Figure 2.4
![Page 7: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/7.jpg)
Filling shells – Na and Cl
Na has only 1 electron in theouter (3rd) shell
Na+
Cl–Cl needs 1 moreelectron in theouter (3rd) shell
Figure 2.5
![Page 8: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/8.jpg)
Alkali metals and halogens reactTransfer of an electron+1 –1
Noblegases
![Page 9: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/9.jpg)
The result: two ions
Each ion is much more stable than the neutral atoms
The two ions are attracted toeach other bythe electrical charge(similar to
magnets)
Box 2.2
![Page 10: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/10.jpg)
Ionic bonds hold together NaCl
The 3-D repeating structure is a crystal,and forms the mineral halite
Figure 2.18
![Page 11: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/11.jpg)
Covalent bonding of water
The hydrogen atoms and the oxygen sharetwo electrons in theouter electron shell
Forms a covalent bond
![Page 12: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/12.jpg)
Bonds between atoms & molecules
Covalent bonds – the electrons are sharedbetween the atoms, keeping the nuclei close together
Metallic bonds – nuclei stay close together,but the electrons are free to flowalong a group of atoms
Ionic bonds – electrons stay on one atom, creating positive and negative ions
Hydrogen bonding (between molecules)
Strong
Weak
![Page 13: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/13.jpg)
Crystals of carbon
Different configurations of covalent bonds
Diamond Graphite
![Page 14: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/14.jpg)
Covalent bonds are generally strongest
Examples from the textbook: graphite and diamond
Box 2.2
![Page 15: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/15.jpg)
Graphite – 2-D bonding
Sheets of C with strong covalent bonds
Van der Waals bonds between the sheets
** Weak **
Can’t withstand shearing force
![Page 16: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/16.jpg)
Diamond
Interlocked3-D framework
![Page 17: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/17.jpg)
Mineral groups
Table 3.3 in the textbook
![Page 18: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/18.jpg)
Carbonates
Basic polyatomic ion – CO3–2
Most common forms:
Ca+2 CO3–2 calcite and aragonite
(Ca+2, Mg+2) CO3–2 dolomite
** These minerals make up limestone, **and stalactites in caves
![Page 19: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/19.jpg)
Halides (from halogen) – salts
Fluorite – CaF2
Halite – NaCl
![Page 20: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/20.jpg)
Native metals
Native gold
Native gold in quartzhydrothermal
![Page 21: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/21.jpg)
Oxides – metals combined with oxygen
Commonly with water (oxyhydroxides)
Limonite – iron oxyhydroxide
![Page 22: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/22.jpg)
The sulfides – sulfur with no oxygenGalena – PbS2 lead sulfide
Commonhydrothermalminerals
Pyrite –FeS2 iron sulfide
![Page 23: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/23.jpg)
Sulfates – sulfur with oxygen
Basic polyatomic ion – SO4–2
Some common forms:
Ca+2 SO4–2 * H2O gypsum
CalcanthiteCuSO4 * 5H2O Hydrated Copper Sulfate
Desert Rose
![Page 24: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/24.jpg)
The silicates – most of the planet
Basic polyatomic ion – SiO4–4
Most common forms:
Olivine (Fe,Mg) SiO4
Feldspar (X Al Si3O8) X = Ca, Na, K
Quartz SiO2
![Page 25: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/25.jpg)
Two major groups of silicates:
FerromagnesianFe Mg SiO4– iron & magnesium silicates
** most common minerals on Earth **make up most of the mantle
and oceanic lithosphere
Non-ferromagnesianX SiO4– silicates without Fe & Mg
typically substitute Ca, Na, K
** most common minerals of continents **make up most of granite
![Page 26: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/26.jpg)
Telling them apart
Ferromagnesian dark, black or greenish
![Page 27: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/27.jpg)
Telling them apart
Non-ferromagnesian light, white, or clear
![Page 28: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/28.jpg)
Minerals and igneous rock types
Granite – Diorite – Gabbro
![Page 29: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/29.jpg)
A quick review: Phases of matter
![Page 30: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/30.jpg)
States (or Phases) of Matter
GAS LIQUID SOLID
![Page 31: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/31.jpg)
What Is Heat?
Heat results from the vibrations of atoms – this is kinetic energy
Heat is transferred along a gradientconductive – particle to particleradiative – by electromagnetic
radiation infra-red radiation
Heat is measured with a thermometerBUT, how does a thermometer work?
![Page 32: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/32.jpg)
The effect of heat on density of matter
Density = mass per unit volume
Cool rock
Hot rock
ADD HEAT
Expands
What changed?Mass
VolumeDensity
![Page 33: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/33.jpg)
The effect of heat on density of matter
As temperature increases:
atoms (or molecules) vibrate fasterand with greater amplitude
these vibrations “push” the atoms farther apart
which lowers the density of the material
So… how does a thermometer work?
![Page 34: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/34.jpg)
Phase Transitions
Melting is the transition from solid to liquidfreezing is the reverse
Evaporation (vaporization) is the transition from liquid to gascondensation is the reverse
![Page 35: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/35.jpg)
Controls on phase transitions
Phase transitions are controlled by:heat (energy available – outward force)pressure (constraining force)
![Page 36: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/36.jpg)
Phase transitions and rocks
Most rocks are made of more than onemineral.
Each mineral melts at a differenttemperature.
So, a rock can be partially molten –with liquid in between solid crystals
![Page 37: Minerals in granite](https://reader030.vdocuments.net/reader030/viewer/2022012800/61bd030161276e740b0e7328/html5/thumbnails/37.jpg)
Phase transitions and rocks
Can a rock in the upper mantle meltwithout an increase in temperature?
Rock initially at a temperature close to melting
Earth surface
Uplifted,pressure reduced
Partial melting
Produces magma