Download Atmosphere

General Geology 89.101
Professor Lori Weeden
978-934-3344
[email protected]
Office: Olney 402b
Text: Wicander, R & Monroe, JS (2010)
GEOL 1st ed. Brooks Cole
Introduction and what to expect…..
http://faculty.uml.edu/lweeden
Chapter 1
Understanding Earth:
A Dynamic and Evolving Planet
Large Granite Batholiths of Yosemite Valley
Learning Objectives
LO1:Define geology
LO2:Understand the impact the formulation of
theories has had on the study of geology
LO3:Explain how geology relates to the
human experience
LO4:Explain how geology affects our
everyday lives
Learning Objectives, cont.
LO5:Describe global geologic and
environmental issues facing humankind
LO6:Describe the origin of the universe and
solar system, and Earth’s place in them
LO7:Explain why Earth is a dynamic and
evolving planet
LO8:Describe the rock cycle
Learning Objectives, cont.
LO9:Understand organic evolution and its
role in the history of life
LO10:Describe geologic time and
uniformitarianism
LO11:Explain how the study of geology
benefits us
Earth as a System
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Atmosphere
Biosphere
Hydrosphere
Lithosphere
Mantle
Core
Evaporation, condensation,
and precipitation transfer
water between atmosphere
and hydrosphere, influencing
weather and climate and
distribution of water.
Plant, animal, and human
activity affect composition of
atmospheric gases.
Atmospheric temperature and
precipitation help to determine
distribution of Earth’s biota.
Atmosphere
Atmospheric gases and
precipitation contribute to
weathering of rocks.
Plants absorb and transpire water.
Water is used by people for domestic,
agricultural, and industrial uses.
Hydrosphere
Plate movement affects size,
shape, and distribution of
ocean basins. Running water
and glaciers erode rock and
sculpt landscapes.
Biosphere
Water helps determine abundance,
diversity, and distribution of
organisms.
Heat reflected from land surface affects
temperature of atmosphere. Distribution
of mountains affects weather patterns.
Plate
Organisms break down rock
into soil. People alter the
landscape. Plate movement
affects evolution and
distribution of Earth’s biota.
Convection cells within
mantle contribute to
movement of plates
(lithosphere) and recycling
of lithospheric material.
Mantle
Supplies heat
for convection
in mantle
Core
Stepped Art
Fig. 1-1, p. 4
Geology Definition
• Study of Earth
• Study of planets and moons
• Physical geology
– Minerals
– Rocks
– Physical processes
Geology Definition, cont.
• Historical geology
– Origin of Earth
– Evolution of Earth
• Resource geology
• Environmental geology
Geology Definition, cont.
• Geologic engineers
• Predictions
– Earthquakes
– Volcanoes
– Mass movements
Theory
• Definition: coherent explanation of
natural phenomena supported by large
body of objective evidence
• Scientific method
– Gather and analyze facts and data
• Hypotheses: tentative explanations that
explain observed phenomena
Theory, cont.
• Importance of testing
• Theory: a hypothesis that survives
repeated testing
• Plate tectonics as theory
• Evolution as theory
Geology and the
Human Experience
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Art
Music
Literature
Empires: rise and fall based on
geography and availability of natural
resources
Hematite?
Limonite?
Malachite?
Azurite?
Geology and Daily Life
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Electricity generation
Minerals
Concrete
Windows
Building materials
Metals and alloys
Plastics
Road materials
9203 kg
Clays
348 kg
Zinc
774,000 kg
Stone, sand,
and gravel
311,034 l
Petroleum
14,359 kg
Salt
159,880 m3
Natural gas
33,771 kg
Cement
>30,615 kg
Other minerals
and metals
14,694 kg
Iron ore
410 kg
Lead
2438 kg
Bauxite
(Aluminum)
260,530 kg
Coal
629 kg
Copper
44 g
Gold
8301 kg
Phosphate rock
So, how does the Gulf Oil Spill compare to daily US
consumption of crude oil?
As of June 22nd, the
amount of oil spilled
accounts for only 2 hours
worth of US crude oil
consumption.
Economic and Political Power
• Topography affects wars
• Topographic features as natural
boundaries
• Resource distribution affects fortunes of
countries
Issues: Overpopulation
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6.7 billion in 2007
7.7 billion in two decades
Increased resource demand
Increased risk from geological hazards
Issues: Global Warming
• Carbon cycle
• Carbon dioxide increasing in
atmosphere
• Greenhouse effect: gases trap heat and
make Earth habitable
• Greenhouse gases:
– Carbon dioxide, methane, nitrous oxide,
chlorofluorocarbons, water vapor
– very effective at trapping heat
– have increased over last two centuries
Issues: Global Warming, cont.
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Temperature increases
Rainfall patterns shift
Sea level rise
Uncertainty about consequences
It’s really not that complicated…
a) Short-wavelength
radiation from the Sun that
is not reflected back into
space penetrates the
atmosphere and warms
Earth’s surface.
b) Earth’s surface radiates heat in the
form of long–wavelength radiation
back into the atmosphere, where
some of it escapes into space. The
rest is absorbed by greenhouse
gases and water vapor and
reradiated back toward Earth.
c) Increased concentrations of
greenhouse gases trap more
heat near Earth’s surface,
causing a general increase in
surface and atmospheric
temperatures, which leads to
global warming.
Stepped Art
Fig. 1-5, p. 9
Origin of the Universe
• Universe has no edge and no center
• Big Bang and origin of the universe:
– 14 billion years ago
– Initially hot and dense
– Now expanding and cooling
• Hubble and receding galaxies
• Cosmic background radiation: afterglow
of Big Bang
Solar System
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8 planets
1 dwarf planet (planetoid)…poor Pluto….
101 moons
asteroids
comets
Solar System Origin
• Solar nebula theory: condensation and
collapse of interstellar material
• Planetesimals: smaller bodies that
eventually collided and coalesced to
form planets
• Terrestrial planets: Earthlike, smaller,
rocky, inner solar system
Solar System Origin, cont.
• Jovian planets: small rocky cores,
mostly gas, outer solar system
• Sun formation: material condensed in
center and became dense and hot
• Asteroids formed between Mars and
Jupiter
• Comets formed near Uranus and
Neptune
Earth’s Evolution
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Began 4.6 billion years ago
Initially cool and uniform
Heated by impacts, gravity, radioactivity
Differentiation of layers
Earth’s Layers
• Based on differences in:
– density
– composition
– temperature
– pressure
Earth’s Layers, cont.
• Inner core: solid
• Outer core: liquid
• Mantle
– Lower mantle: solid
– Asthenosphere: plastic flow
– Upper mantle: solid
Earth’s Layers, cont.
• Lithosphere
– Upper mantle
– Oceanic crust
– Continental crust
– Tectonic plates
Plate Tectonic Theory
• Unifying theory in geology
• Rigid lithospheric plates that move
• Movement caused by thermal
convection cells in mantle
Plate Tectonic Theory, cont.
• Along/near plate boundaries:
– Separation
– Convergence
– Slide sideways
– Earthquakes
– Volcanoes
Mid-oceanic ridge
Trench
Ocean
Subduction
Oceanic
lithosphere
Continental
lithosphere
Convection
cell
Cold
Upwelling
Outer
core
Hot
Mantle
Inner
core
Stepped Art
Fig. 1-12, p. 15
Rock Cycle
• Rock: aggregate of minerals
• Minerals: composed of elements
• Rock cycle: interrelationships between
Earth’s internal and external processes,
and the 3 major rock groups
• Driven in part by plate tectonics
Igneous Rocks
• Crystallization of cooling magma or lava
• Intrusive igneous rocks cool slowly
underground from magma: granite
• Extrusive igneous rocks cool quickly at
the surface from lava: basalt
Sedimentary Rocks
• Consolidation of mineral or rock
fragments: conglomerate
• Precipitation of minerals from solution:
limestone
• Compaction of plant or animal remains:
coal
Metamorphic Rocks
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Alteration of other rocks
Heat
Pressure
Chemically active fluids
Foliated: parallel alignment of minerals - gneiss
• Nonfoliated: no obvious mineral
alignment -- quartzite
Organic Evolution
• All organisms related
• Darwin On the Origin of Species 1859
• Natural selection: best adapted
organisms will pass on genetic traits to
offspring
• Fossil record supports theory of
evolution
• Plate tectonics shaped course of
evolution
Geologic Time
• Geologic time scale
– Helps understanding of Earth’s evolution
and the evolution of life
• Principle of uniformitarianism
– Natural processes have always operated in
the same way
Geologic Time
Scale