Portland Community College | Portland, Oregon

Physical Geology G201 is intended for both geology majors and nonmajors, and is the first term of a year of beginning college geology. Physical Geology is concerned with earth materials and geologic processes acting on the earth. G201 deals mainly with rocks and minerals, and introduces students to internally-driven geologic processes. This course can be used to partly fulfill graduation requirements for the Associate Degree, and has been approved for block transfer. The text and materials have been chosen by the faculty and the emphasis of the course will be the viewpoint of the author(s). This includes the concepts of geologic time and the evolution of the Earth.
Regarding the teaching of basic geologic principles (such as geologic time and the theory of evolution), the Portland Community College Geology Department stands by the following statements about what is science.
 

1. Science is a fundamentally non-dogmatic and self-correcting investigatory process. A scientific theory is neither a guess, dogma, nor myth. The theories developed through scientific investigation are not decided in advance, but can be and often are modified and revised through observation and experimentation.
2. “Creation science,” also known as scientific creationism, is not considered a legitimate science, but a form of religious advocacy. This position is established by legal precedence (Webster v. New Lenox School District #122, 917 F.2d 1004).
3. Geology instructors at Portland Community College will teach the generally accepted basic geologic principles (such as geologic time and the theory of evolution) not as absolute truth, but as the most widely accepted explanation for our observations of the world around us.
4. Because “creation science”, “scientific creationism”, and “intelligent design” are essentially religious doctrines that are at odds with open scientific inquiry, the Geology/General Sciences SAC at Portland Community College stands with such organizations as the National Association of Geoscience Teachers, the American Geophysical Union, the Geological Society of America, and the American Geological Institute in excluding these doctrines from our science curriculum.

Students are expected to be able to read and comprehend college-level science texts and perform basic mathematical operations in order to successfully complete this course.

Upon completion of the course students should be able to:

1. Use an understanding of rock and mineral characterization and classification to infer the geologic processes which formed individual rock and mineral specimens.
2. Analyze the development, scope, and limitations of plate tectonics and utilize plate tectonics to explain the Earth’s earthquake and volcanic activity as well as the occurrence of common rocks, minerals, and economic deposits.
3. Access earth science information from a variety of sources, evaluate the quality of this information, and compare this information with current models of solid earth processes, identifying areas of congruence and discrepancy.
4. Make field and laboratory-based observations and measurements of rocks and minerals and/or Earth’s internal process, use scientific reasoning to interpret these observations and measurements, and compare the results with current models of solid earth processes identifying areas of congruence and discrepancy.
5. Use scientifically valid modes of inquiry, individually and collaboratively, to critically evaluate the hazards and risks posed by volcanoes and earthquakes both to themselves and society as a whole, evaluate the efficacy of possible ethically robust responses to these hazards and risks, and effectively communicate the results of this analysis to their peers.
6. Assess the contributions of physical geology to our evolving understanding of global change and sustainability while placing the development of physical geology in its historical and cultural context.

The material in this course will be presented in a combination of lecture/discussion and laboratory exercises. Other educationally sound methods may be employed such as guest lectures, field trips, research papers, and small group work.

At the beginning of the course, the instructor will detail the methods used to evaluate student progress and the criteria for assigning a course grade. The methods may include one or more of the following tools: examinations, quizzes, homework assignments, laboratory write-ups, research papers, small group problem solving of questions arising from application of course concepts and concerns to actual experience, oral presentations, or maintenance of a personal work journal.

1. Distinguish between rocks and minerals
2. Describe the major types of materials that make up the Earth's crust and explain how each material relates to the rock cycle
3. Describe and use the properties involved in mineral identification
4. Classify commonly occurring minerals
5. Classify commonly occurring igneous, sedimentary and metamorphic rocks
6. Develop an understanding of the origin, activity, structure, and kinds of volcanoes
7. Describe the relationship of volcanoes and earthquakes to plate tectonics
8. Understand how earthquakes are generated
9. Use three earthquake records to locate the epicenter of an earthquake
10. Describe how earthquakes can be used to study the interior of the Earth
11. Discuss the evidence supporting the theory of plate tectonics
12. Examine weathering and the formation of soils (this topic may be covered in either G201 or G202 at the discretion of the instructor)
13. Develop an understanding of the kinds and origins or geologic structures (this topic may be covered in either G201 or G202 at the discretion of the instructor)
14. Examine the role of plate tectonics in shaping the surface of the Earth
15. Describe the structure and composition of the interior of the Earth

Topics to be covered include:
 

1. Minerals
   1. Chemistry and bonding
   2. Structure of atoms
   3. Identification (color, luster, streak, hardness, cleavage, fracture, other features)
   4. Terrestrial abundances of elements
2. Igneous Rocks
   1. Formation and crystallization of magma (partial melting, Bowen’s reaction series)
   2. Classification (texture and chemistry)
   3. Intrusive rock structures (neck, dike, sill, batholith)
   4. Relationship to plate tectonics
3. Volcanoes and Volcanism
   1. Relationship between magma chemistry and gas content and type of eruption
   2. Eruptive styles (effusive vs. pyroclastic)
   3. Volcanic Features associated with basaltic volcanism (shield volcano, cinder cone, columnar jointing, fire fountaining, lava channels/tubes, pillow lavas)
   4. Volcanic Features associated with andesitic/rhyolitic volcanism (composite cones/stratovolcanoes, calderas, domes)
   5. Volcanic hazards (lahars, gas emissions)
4. Weathering (may be taught in G202 instead)
   1. Mechanical weathering (frost wedging, abrasion, exfoliation)
   2. Chemical weathering (dissolution/solution, oxidation, hydration)
   3. Factors that affect weathering rates
   4. Products of weathering (sand, clay, iron oxides/hydroxides)
   5. Soil structure
   6. Types of soils (pedocals, pedalfers, laterites)
5. Sedimentary Rocks
   1. Sediment transport and texture (grain size and shape)
   2. Sedimentary structures (bedding (planar, graded, cross), mudcracks)
   3. Lithification (compaction and cementation)
   4. Classification of sediments (clastic/detrital: clay, silt, mud, sand, gravel vs. chemical)
   5. Classification of sedimentary rocks (clastic/detrital: shale, mudstone, siltstone, sandstone, arkose, greywacke, breccia, conglomerate vs. chemical: limestone, chert, coal, evaporates)
   6. Introduction to sedimentary depositional environments (may be left out)
6. Metamorphic Rocks
   1. Conditions promoting metamorphism (heat, pressure, fluids)
   2. Types of metamorphism (contact, regional)
   3. Causes of foliation
   4. Common metamorphic rocks (slate, phyllite, schist, gneiss, marble, quartzite, hornfels)
   5. Relationship to plate tectonics
7. Structural Geology (may be taught in G202 instead)
   1. Stress and strain
   2. Folds (syncline, anticline, dome, basin)
   3. Faults (normal, reverse, strike-slip)
   4. Strike and dip
   5. Mountain building and relation to stress
   6. Relationship to plate tectonics
8. Earthquakes
   1. Epicenter vs. focus
   2. Seismic waves (P, S, surface)
   3. Magnitude scales vs. Intensity scale
   4. Locating an earthquake epicenter
   5. Earthquake hazards
   6. Relationship to plate tectonics
9. Earth’s Interior
   1. Chemical layers of Earth (crust, mantle core) vs. Mechanical layers (lithosphere, asthenosphere, lower mantle/mesosphere, outer core, inner core)
   2. Using seismic waves to explore Earth’s interior
10. Plate Tectonics
    1. Alfred Wegener and evidence for continental drift
    2. Magnetic reversals and sea-floor spreading
    3. Using hot spots to determine plate motions
    4. Rifting and the origin of ocean basins
    5. Features associated with each type of plate boundary (divergent, convergent, transform)
    6. Ophiolites
    7. Subduction and related volcanism
    8. Continental collisions and relationship to mountain building
    9. Convection as a driving force of plate tectonics