Geology of the Pacific Northwest

Course Number: G 207
Transcript Title: Geology of the Pacific N.W.
Created: September 1, 2012
Updated: June 6, 2017
Total Credits: 3
Lecture Hours: 30
Lecture / Lab Hours: 0
Lab Hours: 0
Satisfies Cultural Literacy requirement: No
Satisfies General Education requirement: Yes
Grading options: A-F (default), P-NP, audit
Repeats available for credit: 0


MTH 65 or equivalent placement test scores

Prerequisite / Concurrent

Course Description

Introduces the regional geology of the Pacific Northwest with emphasis on Oregon geology. Includes basic geologic principles, earth materials and geology of Pacific Northwest provinces. Prior geology experience strongly recommended. Prerequisite: MTH 65 or equivalent placement test scores. Prerequisite/concurrent: WR 121. Audit available.

Intended Outcomes

A student who successfully completes this course should be able to:

  1. Use an understanding of earth materials and landforms to infer the surficial and internal processes which formed the landscape and underlying geology of the physiographic provinces of the Pacific Northwest.
  2. Use an understanding of plate tectonics and surficial processes to unravel the sequence of geologic events which have acted over time to create the physiographic provinces of the Pacific Northwest from diverse geologic terrains.
  3. Access earth science information about the Pacific Northwest from a variety of sources, evaluate the quality of this information, and compare this information with current models of the formation and development of the physiographic provinces of the Pacific Northwest identifying areas of congruence and discrepancy.
  4. Make field and laboratory based observations and measurements of earth materials and landforms, use scientific reasoning to interpret these observations and measurements, and compare the results with current models of geological processes affecting the Pacific Northwest 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 the geological processes which are still shaping the Pacific Northwest both to themselves and society as a whole, evaluate the efficacy of possible ethically robust responses to these risks, and effectively communicate the results of this analysis to their peers.
  6. Assess the contributions of physical and historical geology to our evolving understanding of global change and sustainability while placing the development of the geology of the Pacific Northwest in its historical and cultural context.

Alignment with Institutional Core Learning Outcomes

In-depth 1. Communicate effectively using appropriate reading, writing, listening, and speaking skills. (Communication)


2. Creatively solve problems by using relevant methods of research, personal reflection, reasoning, and evaluation of information. (Critical thinking and Problem-Solving)
3. Extract, interpret, evaluate, communicate, and apply quantitative information and methods to solve problems, evaluate claims, and support decisions in their academic, professional and private lives. (Quantitative Literacy)


4. Appreciate cultural diversity and constructively address issues that arise out of cultural differences in the workplace and community. (Cultural Awareness)


5. Recognize the consequences of human activity upon our social and natural world. (Community and Environmental Responsibility)

Outcome Assessment Strategies

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, 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.

Course Activities and Design

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

Course Content (Themes, Concepts, Issues and Skills)

  1. Locate the physiographic provinces of the Pacific Northwest on a map.
  2. Explore the rock types and geologic features of each of the physiographic provinces of the Pacific Northwest.
  3. Identify and describe the major features of the Earth's surface and interior.
  4. Describe the major types of materials that make up the Earth's crust and explain how each material relates to the rock cycle.
  5. Describe the geologic processes and features that occur at plate boundaries.
  6. Describe the impact of surficial processes on landscapes and geologic materials.
  7. Identify the role of volcanism and faulting in the development of the High Lava Plains and the Basin and Range Provinces.
  8. Describe the roles of flood-type volcanism, catastrophic flooding, and glaciation in the development of the Columbia Plateau.
  9. Compare the geologic histories of the Western Cascades, High Cascades, and North Cascades provinces.
  10. Discuss the formation of the Puget Sound and Willamette Valley.
  11. Describe the role of accretion and crustal deformation in the development of the Klamath Mountains and Blue Mountains.
  12. Describe the role of subduction in the development of the Coastal ranges and the Cascades.
  13. List the major divisions of the standard geologic time scale.

Topics to be covered include:

  1. Physiographic Provinces
    1. Landscape, climate, and vegetation of the Pacific Northwest
    2. Physiographic provinces of the Pacific Northwest
  2. Earth’s Surface Composition and Structure
    1. Regolith vs. bedrock, sources of regolith, variations in depth of regolith
    2. The three rock types; common examples, processes of formation
    3. Occurrence of rocks, cover vs. basement, horizontal vs. folded and faulted strata, types of intrusions, structure of mountain ranges, geologic maps
    4. Rock cycle; internal process vs. surficial processes, energy sources for internal and surficial processes
    5. Continental crust vs. oceanic crust; differences in composition and thickness
  3. Historical Geology
    1. Principles of relative and absolute dating
    2. Fossils, faunal succession, stratigraphic correlation
    3. Past environments; sedimentary evidence for past geographies and climates
    4. Geologic time scale
  4. Plate Tectonics
    1. Basic idea of plate tectonics, evidence for plate motion, difference between continental and oceanic crust, internal structure of the earth, heat loss
    2. Creation and destruction of oceanic crust at ridges and trenches, age of oceanic crust
    3. Geologic activity and structure at each type of plate boundary (transform, convergent, divergent), cause of earthquakes, volcanism and topography at plate boundaries
    4. Hot spots, hot spot tracks, oceanic vs. continental hot spots, causes of hot spots
  5. Coastal Provinces; Coast Ranges and Olympic Mountains
    1. Major topographic features, drainages, rock units and geologic structures
    2. Paleogrography of Tertiary coast
    3. Coastal processes, evidence for uplift
    4. Modern tectonic setting, accretion, evidence for prehistoric subduction zone earthquakes
  6. Lowland Provinces; Puget Sound and Willamette Valley
    1. Major topographic features, drainages, rock units and geologic structures
    2. Glaciation and ice age floods
  7. The Volcanic Arc: Cascade Mountains Province
    1. Major topographic features, drainages, rock units and geologic structures
    2. Subduction zone volcanism
    3. Tertiary plate tectonic setting of the Pacific Northwest
    4. Old Cascades vs. young Cascades, uplift of Cascade Mountains
    5. Volcanic hazards
  8. Extension and Hot Spots: Basin and Range, Columbia River Plateau and High Lava Plain
    1. Major topographic features, drainages, rock units and geologic structures
    2. Timing of basin and range extension, formation of fault block mountains
    3. Flood basalt volcanism vs. silicic volcanism
    4. Hot Spot volcanism
  9. Accreted Terranes: Kalamath Mountains, Blue Mountains and North Cascades
    1. Major topographic features, drainages, rock units and geologic structures
    2. Accreation of exotic terranes, stacking of terranes, stitching by plutons
    3. Mesozoic plate tectonic setting of the Pacific Northwest
  10. Edge of the Craton: Okanagan Highland and Rocky Mountains
    1. Major topographic features, drainages, rock units and geologic structures
    2. Cratonic sediments, fold and thrust belts
    3. Paleozoic plate tectonic setting of the Pacific Northwest

Department Notes

Geology of the Pacific Northwest (G207) is a one-term introductory course in geology. The purpose of this course is to acquaint the student with basic geologic principles and the general geology of the Pacific Northwest. The emphasis is on the geology of Oregon and Washington. 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 geologic time scale and the evolution of the Earth.

Columbia Gorge Community College Science Department stands by the following statement about regarding science instruction:

Science is a fundamentally nondogmatic and self-correcting investigatory process. Theories (such as biological evolution and geologic time scale) are developed through scientific investigation are not decided in advance. As such, scientific theories can be and often are modified and revised through observation and experimentation. “Creation science", “Intelligent design” or similar beliefs are not considered 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).

The Science Department at Columbia Gorge Community College therefore stands with organizations such as the National Association of Biology Teachers in opposing the inclusion of pseudo-sciences in our science curricula except to reference and/or clarify its invalidity.

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