Transcript Lecture 1

Geol 110
Earth Materials
Lecture: MWF 1:25- 2:15 p.m.
Lab: T 9:30 – 12:15 OR Th 1:30 – 4:30 p.m
Professor: Greg Druschel
Office: Delehanty 321
Office Hours : WF 2:15-3:15 pm
T.A.: Phoebe Judge
Class Goals
• Recognize major rock-forming minerals and other
selected minerals in hand specimen and thin
section
• Master use of several techniques for the
identification of minerals, including the
petrographic microscope and x-ray diffractometer
• Develop the ability to relate crystal chemistry,
crystallographic alignment, and physical attributes
of a mineral to guide identification and assess a
mineral’s origin and history
Grading
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Laboratories
Lab exam
Mid-term exam
Final exam
Adopted mineral paper
Homeworks
Participation
20%
10%
20%
20%
10%
10%
10 %
Where do earth’s materials form?
Structure of the Earth
Plate Tectonics
Spreading centers
Changing landscape
Energy
• We will revisit the concept of energy as a
waveform in many manifestations – light
energy, particle energy, sound energy
• Waves in water are also an expression of
energy, but the expression of that energy has
different forms, a point surfers know well…
Earthquakes
• Energy stored (in faults) due to movement of
plates is periodically released, generating an
earthquake
• Energy transmitted as different types of waves
through the earth – the amplitude of the largest
wave is the strength
• Richter Scale – Logarithmic measure of wave
• Mercalli index – Based on observations of
earthquake damage
Mercalli Intensity
(at epicenter)
Magnitude
Witness Observations
I
1 to 2
Felt by very few people; barely noticeable.
II
2 to 3
Felt by a few people, especially on upper floors.
III
3 to 4
Noticeable indoors, especially on upperfloors, but may not be recognized as an
earthquake.
IV
4
Felt by many indoors, few outdoors. May feel like heavy truck passing by.
V
4 to 5
Felt by almost everyone, some people awakened. Small objects moved. Trees and
poles may shake.
VI
5 to 6
Felt by everyone. Difficult to stand. Some heavy furniture moved, some plaster
falls. Chimneys may be slightly damaged.
VII
6
Slight to moderate damage in well built, ordinary structures. Considerable damage
to poorly built structures. Some walls may fall.
VIII
6 to 7
Little damage in specially built structures. Considerable damage to ordinary
buildings, severe damage to poorly built structures. Some walls collapse.
IX
7
Considerable damage to specially built structures, buildings shifted off
foundations. Ground cracked noticeably. Wholesale destruction. Landslides.
X
7 to 8
Most masonry and frame structures and their foundations destroyed. Ground
badly cracked. Landslides. Wholesale destruction.
XI
8
Total damage. Few, if any, structures standing. Bridges destroyed. Wide cracks in
ground. Waves seen on ground.
XII
8 or greater
Total damage. Waves seen on ground. Objects thrown up into air.
Water
• 70% of the surface of the earth is covered
with water
• The interaction of water with rocks is
responsible for many reactions in the crust
• Water is the one universal requirement for
life as we know it – the range of conditions
we know life to be present is constrained by
the H2O being a liquid
Energy
• We will revisit the concept of energy as a
waveform in many manifestations – light
energy, particle energy, sound energy
• Waves in water are also an expression of
energy, but the expression of that energy has
different forms, a point surfers know well…
Waves
• Any wave motion through any medium (water, air,
rock) does NOT involve any transfer of mass, i.e.,
a tsunami does not carry water particles thousands
of miles
• Why does a wave have a physical manifestation
then?
• Particles are affected by energy, but they are
displaced, returning to their original state – water
waves can displace particles up, down, sideways,
and circularly  shallow waves generate circular
displacement, causing breaking
Tsunamis
• Tsunami wave is generated by a physical
displacement – earthquake WITH ground
rupture, landslides, glacial ice calving, etc.
• Extremely high energy, but the wave in the
open ocean is very small…
• Energy of the wave
extends to the bottom of
the ocean (wind-generated
waves are much lower
energy!)
Volcanic provinces
Mt. Pinatubo
Lava
Volcanic settings
Cinder cones
Explosive eruptions
Volcanic provinces
Hot spots
Hot spots
Basalt flows
Plutons
Intrusions
Metamorphic settings
Orogenic settings
Ore deposits
Oil
Weathering
• How is massive rock broken down and
transported?
Sedimentary deposition
• Weathering of any rock and transport of that
material to lower E environment followed by
lithification yields sed. rx
Depositional settings
• Keyed to transport of
physical/ chemical
components of parent
material
• Tells 2 stories – who
were the parents and
how far away did it
go?
Chemical deposition
• Formation of minerals
from aqueous solution
requires some
change in
environment for the
ions to precipitate
Fossils
• Here parent material were organisms – usually
ones that were partially composed of a durable
mineral material
• Requires a special depositional setting
– Quick burial, fine/ chemical covering, replacement
reactions
• Also tell us approximate age of deposition
Biominerals
• Microorganisms may
also have a significant
impact on mineralogy!
A word about classification…
• Umbrella terms
• Mineral nomenclature α taxonomy of
animals, plants, and microbes