What is physical geology

Earth SC-202 Physical Geology


Instructor
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Prof. Steven Dutch
Office: LS 402
Phone: 465-2246
Email:
Home Page: www.uwgb.edu/dutchs
Office Hours MWF 10:30-11:30, TR 9:30-10:50


What is Physical Geology?
Soils
Weathering
Fossils
Earth History

Erosion

Wind

Water Oceans

Glaciers

Underground Surface
Sedimentary

Rocks

Volcanoes

Metamorphic
Igneous
Earth’s Interior
Intrusions
Plate Tectonics
Earthquakes
Mineral Resources
Mountains

Other Planets


Syllabus
• Introduction to the course
• Minerals
• Igneous Rocks and
Volcanoes
• Weathering and Erosion
• Evolution of Landscapes
• Sedimentary Rocks
• Evolution, Fossils, Geologic

Time
• Glaciers
• Wind and Wave Erosion

• Metamorphism and
Deformation
• Earthquakes and Earth's
Interior
• Continental Drift and Plate
Tectonics
• Resources from the Earth
• Geology of other Worlds


Exams and Grading
Midterm I
Midterm II
Lab
Final
Field Trip
Attendance

50 points
50 points
100 points
80 points
20 points
10 points

Total

300 points

A
AB
B
BC
C
CD
D

270+
255-269
240-254
225-239
210-224
205-210
200-204


Field Trip
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Dates

Mandatory – Absence Excuse Required
8:00 LS Parking Lot, Return 4:15
Casual Clothing – No strenuous hiking
Bring a lunch and fluids
Rest stops provided
Put on your calendar! No excuses!


Lab
• Instructor:
Jennifer Wessel
• Enroll in one
section
• 100 points total


Expectations
• Commitment
– Focus in class

• Professional Conduct
– No talking, texting
– Stay whole period
– Stay vertical and awake

• Use Syllabus
• Know your ID number or bring ID to exams


Sample exam question

• Which is the most desirable property in a
gemstone?
a.
b.
c.
d.

High hardness
Low hardness
Excellent cleavage
Density


Signs of Trouble
• Not making connections
– Lecture, lab, text, on-line, exams

• Not knowing your grade
• Not knowing what to study for
• Not knowing what’s on syllabus


Geology and Other Sciences
Physics

Chemistry

Biology

•Geophysics

•Mineralogy

•Paleontology

•Seismology

•Petrology

•Paleo????ology

•Geochemistry
Astronomy

Geology

•Historical Geology

•Planetary Geology •Economic Geology •Geomorphology
•Helioseismology

•Hydrology

•Oceanography

•Engineering
Geology

•Structural Geology
•Volcanology

Who Geoscientists Are:
• About 30,000 in the U.S.
• Globally, in rich and poor countries, about one
per $50 million GNP.
• Mostly male but changing rapidly (now about
25% female in U.S.)
• Still less than 10% minority in U.S. (moving up
slowly)


Where Geologists Work
• 40 % Private Sector
• 30 % Academic
• 30 % Government


What Geologists Do:
• Locate Geologic Resources
• Geologic Hazard Mitigation
– Geological and Mining Engineering
– Site Study
– Land-Use Planning

• Environmental Protection
– Environmental Impact
– Ground Water and Waste Management

• Basic Research (Furnishes fundamental knowledge

for the applications)


Some Unique Aspects of Geology
Importance of Relationships
• Sequential
• Spatial
Importance of Time
Distinctive Problems of Evidence
• Slow Rates
• Rare Events
• Destruction of Evidence
• Inaccessibility


Some Geologic Rates
Cutting of Grand Canyon
• 2 km/3 m.y. = 1 cm/15 yr
Uplift of Alps
• 5 km/10 m.y. = 1 cm/20 yr.
Opening of Atlantic
• 5000 km/180 m.y. = 2.8 cm/yr.
Uplift of White Mtns. (N.H.) Granites
• 8 km/150 m.y. = 1 cm/190 yr.


Some Geologic Rates
Movement of San Andreas Fault
• 5 cm/yr = 7 m/140 yr.
Growth of Mt. St. Helens

• 3 km/30,000 yr = 10 cm/yr.
Deposition of Niagara Dolomite
• 100 m/ 1 m.y.? = 1 cm/100 yr.


1 Second = 1 Year
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35 minutes to birth of Christ
1 hour+ to pyramids
3 hours to retreat of glaciers from Wisconsin
12 days = 1 million years
2 years to extinction of dinosaurs
14 years to age of Niagara Escarpment
31 years = 1 billion years


Some Unique Aspects of Geology
(Continued)
Reliance on Inference and Deduction
Intrinsically "Unsolvable" Problems
• Ancient Landscapes
• Mass Extinctions
• Ancient Ocean Basins

Scientific Principles in Geology
• Parsimony (K.I.S.S.)
• Superposition
• Uniformitarianism
Using these, plus observation, we establish facts
about Earth Processes


Parsimony
• The simplest explanation that fits all the data
is preferred
• Doesn’t guarantee that things must be simple!
• Theories with lots of ad hoc or unsupported
ideas are probably wrong.


Parsimony: What is the best interpretation
of this well data?


Parsimony

• This?

• Or This?


Parsimony

• Rock layers
throughout NE
Wisconsin are
nearly flat and
little disturbed
• Glacial deposits
are always on
top of bedrock

• Therefore this is
the most likely
interpretation


One Implication of Parsimony
How do we know the laws of nature are the same
everywhere?
• Out to the farthest stars, everything seems to
obey the same laws of nature
• We find nothing in the rocks to suggest the laws
of nature were different in the past
Either:
• The laws of nature change but just happen to
produce effects that look like the presentlyknown laws of nature – or –
• The laws of nature really are the same
everywhere