Transcript Welcome to Geology 101: Introduction to Geology

Welcome to Geology 218:
Environmental Geology
Dr. Ralph Dawes, Instructor
Today’s plan.
Introductions
Syllabus
Active learning is key.
Geology learned by
reaching out, taking part.
HP Compaq tc4200
tablet computer
and Earth, ca. 2005
Image Source:
http://www.dell.com
Talk to another student and
introduce her or him to the rest of the
class in terms of…
First and last name
Town where they live
Geologic hazard or
environmental issue
most interested in
Image Source:
http://www.k5geosource.org/content/esimage/sea.html
Thinking about Earth / Environment
1.
2.
3.
4.
5.
6.
7.
8.
Scientific Method
Empirical, experimental, &
theoretical approaches
History of science/geoscience
Evolution and environment
Population growth and
humanEarth interactions
Earth systems science
Dynamic Earth Systems
Links & Cycles Among Earth
Systems: Matter and Energy
Image Source:
http://www.nasa.com
The Scientific Method
Ideas about nature in terms that are
logical, rational, verifiable, repeatable,
and yield manipulative/predictive power
Mathematical: most elegantly logical
Measurable, observable
Hypothesis (what most people mean
when they say “theory”)
Theory: Verified, repeatedly confirmed,
powerful, insightful, predictive.
Some common misconceptions…
Image source:
http://courses.ncssm.edu/math/CPTA/data/DECAY/decay.gif
Empirical, experimental, & theoretical
Empirical: based on many careful
measurements and observations
Experimental: controlling the variables
Theoretical:
may or may not be mathematically
expressed
provides explanations that account for the
evidence
makes predictions that prove true
E=
Image Source:
http://www.science.smith.edu/departments/Geology/Structure/fieldphotos/4_03/
2
mc
Image Source:
http://www.stevespanglerscience.com/product/1274
History of science/geoscience
Geology was one of the leading sciences
that arose from the Enlightenment
Ranks with physics, chemistry, biology
In 1800…
Chemistry still separating from alchemy
Astronomy separate from astrology for ~200
years (since Copernicus, Kepler, Galileo)
Biology post-Linnaeus, pre-Darwin
Physics 100 years since Newton
Geology still over 200 years old, but age of
Earth not resolved
Image Source: http://www.scottishgeology.com/history/people/james_hutton_image.html
Evolution and environment
Given that natural selection favors those most welladapted to the environment, changing environments are
a key factor in evolution
10,000 years ago wooly mammoths, mastodons, giant
elk, etc. existed, but soon after became extinct, probably
due to environmental change
At that time the earth warmed up from the last glaciation of the
Pleistocene ice ages, driving rapid environmental change
Changes in future earth environments will also change
ecosystems and cause extinction of species
Image source:
http://www.cr.nps.gov/seac/mam-mis.htm
Population growth and
humanEarth interactions
As populations grow and societal infrastructure expands,
so does exposure of society to earth hazards
Hurricanes striking increasingly populated coasts is just one
example
More humans require more resources (or do they?)
Population growth causes:
More land developed
More air, water, and
soil pollution
More floods (why?)
Climate change (why?)
etc.
Image Source:
http://blog.frogbody.com/frogblog/2005/01/
Earth systems science
Atmosphere
Geosphere
Biosphere
Hydrosphere
Dynamic Earth Systems
Follow a molecule of water in the ocean
Into an altered basalt on the ocean floor
Down a subduction zone
Into magma (molten rock)
Up a volcano
Out with a steam-exploded eruption
Into the atmosphere
Down as rain
Etc…One tiny example.
Image Source:
http://www.island-air.com/ScenicTours/Mt%20St%20Helens.htm
Links & Cycles Among Earth
Systems: Matter and Energy
The earth’s surface gets
much of its energy from
the sun:
Wind
Rain
Rivers
Erosion
Hurricanes
Etc.
The earth’s interior gets its
energy from remnant heat of
earth formation plus natural
radioactivity in the rocks:
Volcanoes
Mountain range uplift
Earthquakes
Plate tectonics
Image Source:
Image Source:http://www.
http://www.noaanews.noaa.gov/stories2005/s2372.htm lbl.gov/Science-Articles/Archive/Phys-earth-core.html
Earth Systems
4 main systems:
Atmosphere
Biosphere
Hydrosphere
Lithosphere (Geosphere)
Lithosphere also has other
meanings
Image Source:
http://seis.natsci.csulb.edu/rbehl/300i-L01.htm
Each  Other
Boundaries arbitrary
Energy and matter
Reservoirs and fluxes
Earth systems compositions
Atmosphere
Biosphere
Hydrosphere
Lithosphere (Geosphere)
Image Source:
http://seis.natsci.csulb.edu/rbehl/300i-L01.htm