EAS 100 – Planet EarthLecture Topics Brief Outlines

II. Earth Science (Geology) Section (1/15/2010)

1. Interior of the Earth

Learning objectives: Understand the structure of the Earth’s interior – crust, mantle, core (chemical classification); and lithosphere, asthenosphere (mechanical classification). Learn about the properties of Earth materials – physical/mechanical, chemical, conditions (temperature, pressure).

Reading: Text, pages 175-177

Figures to study: Text, Figures 6.21, 6.22

Topics:Introduction to Earth science (geology) – Earth is dynamic, impact on people, effects of people on the Earth

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Main features of planet Earth

Physical (density, elastic, mechanical properties), chemical (chemical composition, minerals) and condition (temperature, pressure, time) properties of rocks

Earth’s interior structureChemical classification – crust, mantle, outer core, inner

coreMechanical classification – lithosphere, asthenosphere

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2. Chemistry of the Earth

Learning objectives: Learn the definitions of minerals and rocks, and rock types – igneous, metamorphic and sedimentary. Understand how we know about the composition of the Earth’s deep interior. Recognize the significance of the silica tetrahedron.

Reading: Text, pages 18-61

Figures to study: Text, Figures 1.1, 1.2, 1.3, 1.5, 1.7, 1.9, 1.11, 1.13, 1.14, 1.15, 1.19, 1.20, 1.21, 2.2, 2.9, 2.18, 2.30

Topics:Mineral – naturally occurring, inorganic, solid, distinct chemical composition, regular crystal structure, characteristic properties

Rocks – aggregate of minerals

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Average (bulk) composition of the Earth (how do we know what’s in the Earth’s deep interior)

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The Silica tetrahedron (SiO2) – silicate minerals

The Rock Cycle

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3. Plate Tectonics 1

Learning objectives: Learn about the properties of the lithosphere (the plates) and asthenosphere, plate boundaries and basic plate tectonic settings of the world. Understand sea floor spreading, continental drift and the Earth features and processes associated with plate tectonics.

Reading: Text, pages 130-152, 177-188

Figures to study: Text, Figures 5.2, 5.3, 5.4, 5.6, 5.7, 5.8, 5.9, 5.10, 5.11, 5.12, 5.13, 5.14, 5.15, 5.16, 5.17, 5.19, 5.24, 5.25, 5.26

Topics:Properties of the lithosphere (plates) and asthenosphere

Mechanical properties – elastic, brittle, ductile

Plate boundaries – divergent, convergent, transform

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Plate tectonic processes at the plate boundaries – sea floor spreading, subduction, continental collision, associated earthquake and volcanic activity

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Continental drift

4. Plate Tectonics 2

Learning objectives: Examine the evidence for plate tectonics. View examples of plate processes at divergent, convergent and transform boundaries. Compare the hypotheses for the “driving mechanism” for plate tectonics.

Reading: Text, pages 131-155, 182-188

Figures to study: Text, Figures 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 5.10, 5.11, 5.12, 5.13, 5.14, 5.15, 5.16, 5.17, 5.19, 5.24, 5.25, 5.26, 5.27, 5.28

Topics:Evidence supporting the theory of plate tectonics

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Examples of plate boundaries and associated features (topography, age, etc.) and processes (volcanism, earthquake activity, etc.)

The driving mechanism of plate tectonics, hypotheses – ridge push, slab pull, mantle convection, mantle plumes – all due to heat within the Earth

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5. Geological Hazards, Earthquakes 1

Learning objectives: What are earthquakes? Understanding the connection between plate tectonics and the cause of earthquakes – the elastic rebound theory. Learn about earthquake waves, basic earthquake statistics, and seismicity (where and how often do earthquakes occur).

Reading: Text, pages 160-177

Figures to study: Text, Figures 6.2, 6.4, 6.5, 6.7, 6.8, 6.9, 6.10, 6.11, 6.13, 6.14, 6.15

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Topics:Why study earthquakes?

What are earthquakes?

The elastic rebound theory

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Earthquake (seismic) waves

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http://www.eas.purdue.edu/~braile/edumod/waves/WaveDemo.htm

Earthquakes at plate boundaries – examples from California (transform boundary), mid-ocean ridge earthquakes (divergent

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boundary) and collision zones (convergent, subduction boundary)

6. Geological Hazards, Earthquakes 2

Learning objectives: Understanding earthquake magnitude and intensity. Evaluating the earthquake hazard – Where do earthquakes occur? How often do earthquakes occur? What is the maximum magnitude and intensity of shaking expected? View examples of earthquake damage and hazards.

Reading: Text, pages 160-177

Figures to study: Text, Figures 6.2, 6.4, 6.5, 6.7, 6.8, 6.9, 6.10, 6.11, 6.13, 6.14, 6.15

Topics:Earthquake magnitude and intensity; earthquake shaking

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The frequency-magnitude relation (how often do earthquakes occur?)

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Effect of location (how close to a fault zone?)

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Effects of geology – attenuation, soil conditions, liquefaction

Effects of building design

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Examples of earthquake damage; earthquake safety

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Paleoseismology, earthquake prediction

7. Geological Hazards, Volcanoes, Hawaiian Volcanism

Learning objectives: Learn of the significance of volcanoes in Earth history, the relationship to plate tectonics, and as natural hazards. Understand the properties that control the eruption intensity (“explosiveness”) of a volcano. Examine

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volcanic activity and characteristics of two classic volcano systems – the Hawaiian Islands and Mt. St. Helens.

Reading: Text, pages 194-219

Figures to study: Text, Figures 7.1, 7.2, 7.4, 7.5, 7.7, 7.8, 7.9, 7.10, 7.12, 7.14, 7.15, 7.16, 7.18, 7.19, 7.26, 7.27, 7.28, 7.29

Topics:Importance of volcanoes in Earth history

Relationship to plate tectonics

Main types of volcanoes – shield and composite volcanoes are most important

***** Two major types of volcanism – basaltic and rhyolite/andesite(differences in composition, volcano shape, density, tectonic setting, melting point, viscosity)

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Examples: Hawaiian volcanism and Mt. St. Helens

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8. Geology of the National Parks, Indiana Geology

Learning objectives: View examples of geological features that are well-displayed at US National parks. Examine the geologic history, natural resources, natural hazards and surface features of Indiana and the Midwestern US.

Reading: – No specific reading, see figures below (and captions and accompanying text description) which illustrate geological features that are well displayed in US National Parks

Figures to study: Text, Figures 2.1, 2.3, 2.14, 2.16, 3.1, 3.17, 3.19, 3.31, 3.39, 4.1, 4.6, 4.7, 4.9, 4.13, 4.20, 4.26, 4.32, 7.1, 7.4, 7.18, 7.25, 8.2

Topics:View examples of various geologic features (volcanoes, calderas, mountain ranges, sedimentary sequences exposed in canyons, glaciation, hydrothermal, etc.)

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Indiana geology – major events in geologic history of Indiana and the Midwestern US; relationship to plate tectonics

1. Continental volcanism» 1.4 billion years ago

2. Rifting and collision event» 1.1 billion years ago

3. Continental separation (similar to the continental separation which took place about 200 mya – the breakup of Pangea)

(buried faults, earthquake hazard)» 600 million years ago (mya)

4. Paleozoic marine sediments» 550 – 280 mya

Basins – petroleum, coal, limestone, shale

5. Mesozoic to Cenozoic» 200 mya to present

Uplift, erosion

6. Pleistocene(last 2 million years) -- Glaciation -- Sand and

Gravel, groundwater resources

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Natural resources (petroleum, coal, building materials, groundwater)· Resources

-- Petroleum (oil and gas)-- Coal-- Building materials

limestone (agricultural lime, gravel, building stone)

-- Groundwater(mostly in glacial deposits)

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Natural geologic hazards (earthquakes, floods, groundwater contamination, landslides)· Hazards (natural, geologic)

-- Earthquakes-- Floods-- Groundwater contamination-- Landslides

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The earthquake hazard in the Midwestern US – causes; probabilities; reducing the earthquake hazard

1. Before-- Know what to do in case of an earthquake-- Make home/office safer-- Have disaster supplies

2. During-- If indoors, stay there

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-- Take cover (desk or table)-- If outdoors, stay there, move to open area

3. After-- Check utilities, especially gas lines-- Be prepared for aftershocks

(evacuate weakened structures)

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