intro chapter to the course

1. SC1150
need
a
science
ENVIRONMENTAL GEOLOGY
need to
know
other:
told I had
to; needed
elective;
important
for career
interesting
sounds
easy
Where should we spend
our money in MN?
Ranked answers
QUIZ 0 RESULTS
This group:
- Needs a science course (27%)
- Finds geo interesting  (33%)
- Feels the info is necessary (27%)
- Does not expect EnvGeo to be easy 
…

2. SC1150
ENVIRONMENTAL GEOLOGY
QUIZ 0 RESULTS: most people already know some geology
T
F
water = over half Earth’s surface
93%
7%
water = over half the Earth’s volume
75%
25%
rocks are made of minerals
100%
there’s more oil than coal
25%
75%
drought is a MN concern
81%
19%
glaciers were important in MN landscape
88%
13%
Just one sticking point !
Jeff Bartlett
jbartlett@national.edu

3. Your news items: ripped from the headlines

4. The Basic Idea
This course includes the examination
of Earth processes that influence
human activities.
Topics include Earth
development, rocks and
minerals, internal Earth
processes, surface Earth
processes, Earth
resources, pollution, and
waste disposal.
Environmental Geology
jbartlett@national.edu

5. Connects the
lithosphere to the
hydrosphere, atmos
phere, biosphere &
human sphere
Environmental Geology
jbartlett@national.edu

6. Hypothesis is formed to explain
observations or data
Makes predictions to test
repeatedly and systematically
Conclusion includes direction for
further questions - actually
continues a cycle
wired.com
But really – is this how our investigations work?
Chaos – accidents and dead ends are
very very common
Mysteries drive curiosity
Practical issues drive projects
Economics is important for stakeholders
Environmental Geology
jbartlett@national.edu

7. Examples of traditional
experimental science
Actual hypothesis – experiment – result type process
Environmental Geology
jbartlett@national.edu

8. Geology has unique issues
A pressing environmental issue:
Tuvalu and sea level change
Geology is an environmental science
Rocks record how earth has changed
Control of erosion and sedimentation
Extraction of resources
Recognition and mitigation of hazards
Issues with scale
A river is not easily fit within a
laboratory
Plate tectonics involves the whole Earth
Problems with time
Geologic processes take millions of years
Geologists are limited by human time
Problems with resolution of data
New technology and procedures
We can see more details now
Environmental Geology
“Sinking feeling in Tuvalu”
BBC, 2002
“Tuvalu is growing”
jbartlett@national.edu
USGS, 2010

9. What it really takes :
Observation– either natural or controlled circumstances
Reasoning drive curiosity
Evidence to collect and assess  important step!
Progress includes
both conclusions
and new questions
Environmental Geology
jbartlett@national.edu

10. Formation of the solar system
Formation of the earth
Composition of the earth
Interaction with humanity
Geologic hazards
Population
Environmental Geology looks at
interactions between humans and
geologic environments
Environmental Geology
jbartlett@national.edu

11. The Big Bang Theory is the dominant scientific theory about the origin of
the universe. widely accepted, but hard to prove
The universe was created 10 - 20 billion years ago from a cosmic
explosion that hurled matter and in all directions.
[latest estimate = 13.8ish]
Very smallest particles were forced into larger particles, then basic
atoms of lightest elements: 1H, 2He, 3Li, and so on up to 16O
Environmental Geology
jbartlett@national.edu

12. Bigger elements had to be fused in stars themselves
… that gets up to iron , 56Fe
What about very heavy
elements like gold, 197Au?
Elements have to form during
solar collapse, and resulting
supernova explosions
The only known process with
energy that can form these
elements…
Environmental Geology
jbartlett@national.edu

13. Planet #3:
g/cc
1.4
• >4 billion years old
• 15 o C, not really too
hot or cold
• Tilted >20º
• Rocky with gases
Environmental Geology
5.6

Formed ~5 billion years ago,
out of swirling mass of gas
and dust - the „solar nebula‟
Planet compositions depended
on distance from the hot sun
near = rocky / metallic   far = gaseous
Nearest planets: metallic iron, few very high temp minerals,
little water or gas. Farther from the sun: lots of low temp
minerals, water, & condensed gases.
jbartlett@national.edu

14. Early Earth – a barren world with a cratered surface
Earth was target of many impacts
Asteroids
Comets
Meteors
Dust Particles
One impact made our moon
As cooling progressed, dense materials [Fe]
sank
lighter, low-density minerals [Si] floated
out toward the surface
=
Environmental Geology
=
jbartlett@national.edu

15. Differentiation 
Core: dense, hot
Ni + Fe
Mantle: thick zone that
surrounds the core
Mushy, hot ultramafic rocks
Crust: Zone of interaction
Oceanic (mafic)continental
(felsic)
Heat from core escapes by
convection, keeping the
planet constantly changing
Environmental Geology
jbartlett@national.edu

16. Heating and differentiation of the early earth formed
crust, atmosphere and oceans.
Minerals released gases
Impacts brought extraterrestrial elements!
Crust has loads of
Si, O, and Al
Atmosphere lacked
free oxygen (O2)
Dominated by
N, CO2 & SO2
A
Environmental Geology
jbartlett@national.edu

17. Very early in the world, life began and
interacted with the earth
Earliest fossils show that bacteria used
ancient atmosphere and „polluted‟ the
seas with O2 Iron rained out of seas
Result – oxygen in the atmosphere, and
iron in the rocks!
This is a great example of a feedback between biosphere, lithosphere and
atmosphere
Ecological interactions were responsible for changing the world:
We would not exist if they hadn‟t
Environmental Geology
jbartlett@national.edu

18. A dangerous place!
Fig 1.6-1.9
Partly because of us:
- Choosing to live near hazards
- Poor understanding
- Contributing to risk
Environmental Geology
jbartlett@national.edu

19. Exponential growth:
• Possibly 9 billion people
by 2050
• Life span & birthrate
up, mortality down
• Mass mobility
Inflection [change] point:
• Acceleration is slowing
to zero
• Population decline in
many countries
Environmental Geology
jbartlett@national.edu

20. Density is highly
variable and depends
on resources, space,
culture, economics etc
Figure 1.15
Figure 1.18
Environmental Geology
jbartlett@national.edu

21. The Earth has some time left before the sun gets too hot. Based on their
models, the scientists calculate that the planet will fall out of the habitable
zone some time in the next 1.75bn to 3.25bn years. Then, the habitable
zone will start beyond Earth's orbit, and make Mars more earth-like
Environmental Geology
jbartlett@national.edu