Download Chapter 4: Earth Materials

USU 1360

Earth Materials

Composition of the Planet

Comparison of Natural Abundance
Observe this view of the Peninsular Ranges near San
Diego, identifying
regions composed
of different
Loose
materials
sediment
Tourmaline in
small pockets
in granite
Granite and
metamorphic rocks
04.00.a
Viewing Geology at Different Scales
Landscape
Hand specimen
Outcrop
Thin section
04.01.a
What Is a Mineral?
Solid
Natural
Inorganic
Ordered internal
structure
Specific
chemical
composition
04.01.b
Observe the differences between these two rocks
Composed of
crystals:
crystalline rock
Composed of
pieces (clasts):
clastic rock
04.02.a
Observe that these rocks have more
than one type of mineral
Crystalline
Clastic
04.02.b
Observe that these rocks have large crystals or clasts
(photos show the same size of polished slab)
Crystalline
Clastic
04.02.b
Observe the shape of crystals or clasts
in these two rocks
Crystalline
Clastic
04.02.b
Observe the layers in these rocks
Crystalline
Clastic
04.02.b
Distinguishing One Mineral from Another
Crystal form
Cleavage
No cleavage
Luster
Color
04.03.a
Tests to Help Identify Minerals
Effervescence
Hardness
Streak
Density
(specific
gravity)
Magnetism
04.03.b
What Controls a Crystal’s Shape?
Internal structure of halite
Halite (NaCl)
Sizes and
packing
of atoms
04.04.a
Crystal Structure
Orderly
arrangement
of atoms in
repeating
pattern
04.04.a2
How Are Atoms Arranged in a Mineral?
Observe some ways atoms are arranged in a mineral
Cube
Tetrahedron
Octahedron
04.04.b
Atomic Scale of Mineral Cleavage
Brown atoms bonded with blue
atoms into flat sheets (strong bonds)
Sheets joined by long bonds
between sheets (break
along weakest bonds)
Cleave into sheets
04.05.a
Bonds with Same Strength
Mineral can break along three sets of planes
without passing through an atom
In other arrangements,
mineral breaks in nearly
any direction so it will
fracture
04.05.b
Observe the number of cleavage planes in this mineral
04.05.c1
One dominant direction of cleavage
(cleaves into sheets)
Observe the number and relative orientation of cleavage
planes in this mineral
04.05.c3
Two perpendicular directions of cleavage
(cleaves at right angles)
Observe the number and relative orientation of cleavage
planes in this mineral
04.05.c5
Two non-perpendicular directions of cleavage
(this mineral cleaves at 60° and 120° angles)
Observe the number and relative orientation of cleavage
planes in this mineral
04.05.c2
Three perpendicular directions of cleavage
(cleaves into cubes and box-shaped pieces)
Observe the number and relative orientation of cleavage
planes in this mineral
04.05.c4
Three non-perpendicular directions of cleavage
(cleaves into rhomb-shaped pieces)
Periodic Table
Letters are abbreviation
for element
# is atomic number
(number of protons)
Color represents type of element
04.06.a
Average Abundances in Earth’s Crust
Oxygen is most
abundant element
Some
abundant
metals
04.10.b1
Silicon is second most
abundant; aluminum
is third
Iron is most abundant
transition metal
Minerals in Different Parts of Earth
Oceanic crust
Continental crust
Upper
mantle
Core
04.10.a
Average Abundances for the Entire Earth
Oxygen most
abundant element
Magnesium is
abundant metal
04.10.b2
Silicon third most
abundant element
Iron and nickel
abundant in core
Sulfur abundant in
core
Silicates in Different Parts of Earth
Oceanic crust
Continental crust
Upper
mantle
Core
04.10.a
Average Abundances for the Universe
Hydrogen is most
abundant
04.10.b3
Helium is second
most abundant
Silicate Minerals
Silicate
tetrahedron
Tetrahedra
bond
together
and with
other
elements
04.07.a
Independent Tetrahedra
Tetrahedra bond to
other elements, not
other tetrahedra
Olivine
04.07.b1
04.08.b3
Single Chains
Tetrahedra bond
together to form
single chains
Pyroxene
04.07.b2
04.08.b2
Double Chains
Tetrahedra bond
to form double
chains
04.07.b3
Amphibole
04.08.b1
Sheet Silicates
Tetrahedra
bond into
sheets, which
may be weakly
connected to
one other
Mica
04.07.b4
04.08.a4
Frameworks
Tetrahedra bonded together
and with other elements
in 3D framework
Quartz
Feldspar
04.07.b5
04.08.a1,3
Major Classes of Rock-Forming Minerals
Carbonates
Oxides
Halides
Silicates
Native minerals
Sulfides
Sulfates
04.06.b1
Nonsilicate Minerals: Carbonates
Calcite
Dolomite
04.09.a
Nonsilicate Minerals: Oxides
Magnetite
Hematite
04.09.a
Nonsilicate Minerals: Sulfides
Pyrite
Galena
Copper
sulfide
04.09.a
Nonsilicate Minerals: Halides and Sulfates
Halite (halide)
Gypsum (sulfate)
04.09.a
Investigation: What Minerals Would You Use
to Build a House?
04.15.a
Different parts of a house
Roof
Insulation
Exterior
walls
Windows
Cement
slab
Interior walls
Plumbing
Electrical wiring
04.15.b1