M
Nov. 10
Earth Materials
(Ch. 10)
1. Internal earth structure F 11.1
2. Crustal materials
a.
elements (and compounds)
b.
minerals (made of elements)
c.
rocks (made of minerals), and the rock cycle. F 10.18
Elements:
substances that can't be broken down into anything simpler by ordinary
chemical means.
Atoms: the
chemical units of matter; the smallest particles into which an element
can be subdivided and retain the
properties of that element.
compounds:
combinations of two or more elements.
molecules: the
physical units of matter; the smallest portions of substances. (molecules are electrically
charged).
¡
¡
.....
°
crust (solid) F
11.1
mantle (solid)
outer core (liquid)
inner core (solid)
Elements are defined
in terms of their atomic structure.
protons and neutrons
are inside the nucleus of an atom.
electrons orbit
around the nucleus.
ion: al
electrically unbalanced atom/group of atoms.
cation:
positively charged ion.
anions:
negatively charged ions.
ions are created by
losing/gaining electrons.
cations - losing
anions - gaining
valence: the
amount of electrons lost/gained in solution.
valence of oxygen = -2
valence of carbon = 4
mineral: a
solid, naturally occurring inorganic element or compound.
(not coal b/c its a carbohydrate, organically produced by
photosynthesis.)
ice
silicon dioxide quartz - one of the most commonly occurring
mineral in the crust.
S1 =
4+
Fe3O4 magnetite - iron ore (remove oxygen
[reduction] to get oil).
Au gold
C carbon - diamond is pure
carbon
rocks - defined by the minerals they are made of
together with their proportions.
granite - defined by
the minerals and proportions of those minerals in it.
granitic rocks -
have the same minerals as granite, but in different proportions.
W
Nov. 12
A rock is defined by
its minerals and their proportions.
Rocks are classified
by how they're formed.
Example
volcanic-------------------------------basalt
ü
¤ (fine grained)
Igneous Rocks á small
crystals
(Crystalline) \
plutonic-------------------------------granite
ü
(course grained)
large crystals
-formed deep in ground
Sedimentary Rocks
--------------------------------------limestone
(Stratified) sandstone
ü
conglomerate ü
Metamorphic Rocks
-------------------------------------quartzite...comes from sandstone
(Changed) gneiss
ü...comes from granite
marble...comes from limestone
ü rocks that originate underground
Magma is a
rock-forming material in the liquid phase (sometimes called a
"melt").
When this reaches
the surface its called lava.
__________
| Magma |
| (liquid) |
¤ õ
crystallization ¤ \ melting
________÷ \ _____________
| igneous| | metamorphic |
| rocks | |
rocks |
erosion | metamorphism (change)
transportation | | (heat and pressure)
deposition ¯
lithification ½
|
sediments |------------® | sedimentary
|
| | (cementation) | rocks |
Igneous rocks are
formed by crystallizing magma.
Basalt made by
crystallizing lava.
Sedimentary rocks
are made by the lithification of sediment (loose accumulation of solid debris).
Stratification -
layers of sediments
Any rock can be
changed through metamorphism.
Any rock can become
sediments through erosion, transportation and deposition.
Any rock can become
magma through melting.
All rocks are made
from other rocks.
To produce crystals,
atoms need time to form orderly arrangements.
If atoms are cooled
quickly, atoms freezed unorderly and it becomes glass.
Atoms in a solid
rock can move around to make crystals grow.
F
Nov. 14
Plate Tectonics
(Ch. 11)
1. Continental drift F 11.19
2. Plate tectonics
a.
plate definitions F 11.2, 11.12
b.
sea floor spreading F 11.10
c.
subduction and suture zones F
11.10, 11.16
3. Energetics
Alfred Wegener -
developed idea of continental drift
- the margins of continents fit
together
n. Laurasia
Protocontinent
(original) - Pangea <
s. Gondwanaland
- drifted apart 220 mya (rocks
older than that match)
continental drift
laughed at, Þ plate tectonics is revised version of
same ideas.
Plates are described
as lithospheric.
The crust is much thinner beneath ocean than continents.
______
mohorovicic ð crust }
Lithosphere -- rigid solid
discontinuity
mantle } (plate)
} Asthenosphere --
plastic solid
} (silly puddy)
plastic solid - a
solid that has the capacity to flow (but doesn't bounce back).
rigid solid - no
capacity to flow
Figure 12.21 is a
map of earth quakes which can be substituted for a map of plates. A world map of volcanoes would be very
similar, too.
Names of Plates: Great Plates: Lesser
Plates:
African Plate Pacific Nazca
Antarctic Plate American (North,
South) Cocos
Arabian Plate Eurasian Philippine
Austral-Indian Plate Persian
Subplate Caribbean
Bismark Plate African Arabian
Caribbean Plate Somalian
Subplate Juan De Fuca
Caroline Plate Austral-Indian Caroline
Cocos Plate Antarctic Bismark
Eurasian Plate Scotia
Juan De Fuca Plate
Nazca Plate
North American Plate
Pacific Plate
Philippine Plate
Scotia Plate
South American Plate
Sea-floor Spreading
midoceanic ridge -
submerged volcanic mountain ranges in the middle of the ocean
If we date the age
of the crystallization of rocks at the ridge it would support the idea of
sea-floor spreading which gives us the direction of plate movement. (Plates move away from ridges.)
ridge - diverging
- trailing edge of plate
- converging margins - subduction
- to thrust under
- leading edge of plate
(trench)
suture - the two plates both turn upward because
neither one could be thrust under.
The energy that
drives the movement of the plates comes from within.
M
Nov. 17
Inventory of
terms
A.
Earth Materials
atom (proton,
neutron, electron)
ion
mineral
igneous rock
(plutonic, volcanic)
sedimentary rock
metamorphic rock
B.
Plate Tectonics
lithosphere
asthenosphere
Pangea
mid-ocean ridge
subduction zone
suture zone
convection cell
radioactive decay
C.
Tectonic (and
Volcanic) Landforms
anticlinal valley
synclinal valley
normal fault
reverse fault
transcurrent
(lateral) fault
graben
horst
tilted fault block
stratovolcano
shield volcano
D.
Exogenous Landforms
gradation
(degradation, aggradation)
erosion,
transportation, deposition
potential energy
kinetic energy
work rate
E.
Valley-Side
Processes
abrasion
base level
rock weathering
slope wash
(gulleying)
mass wasting
(slumping, sliding)
F.
Valley-Floor
Processess and Landforms
floodplain
(alluviation)
braided stream
meandering stream
levee
point bar
meander cut-off
(oxbow lake)
alluvial fan
river delta
G.
Landforms and Rock
Structure
consequent valley,
subsequent valley
landforms from class
exercise
river patterns from
class exercise
H.
Waves and Coastal
Landforms
wave refraction
longshore current
rip current
longshore drifting
beach drifting
pocket beach
spit
abrasion platform,
stack
sea cliff and notch
I.
Glaciers and Glacial
Landforms
Cenozoic era
Quaternary period
firn, ice
till (unstratified
drift)
landforms from class
exercise