Washington Geography and Geology Notes

Washington’s Geography and Geology

1. The Map
  • Five Regions:
    • Coastal Region: West coast of Washington.
    • Puget Sound Lowlands: Eastern half of western Washington.
    • Cascade Mountain Region: Middle of the state.
    • Columbia Plateau: Southeast corner of the state.
    • Rocky Mountain Region (Okanogan Highlands): Northeast corner of the state.
2. Characteristics of Each Region

  • Coastal Region:

    • Cold, rocky, beautiful beaches.
    • Home to the Hoh Temperate Rainforest and Olympic Mountain Range.
    • Industries: Fishing and lumber; now primarily tourism.

  • Puget Sound Lowlands:

    • Most populated region.
    • Hosts major businesses and fertile farmland.
    • Capital city: Olympia.

  • Cascade Mountain Region:

    • Recreational opportunities: skiing, snowboarding, camping, and hiking.
    • Known as “The Cascade Curtain” for dividing eastern and western Washington.
    • Features volcanoes.
    • Notable town: Leavenworth.

  • Columbia Plateau Region:

    • Major agricultural area; crops include:
    • Apples
    • Wheat
    • Cherries
    • Onions
    • Biggest city: Spokane.
    • Washington State University located here.
    • Home to the Palouse wheatfields.

  • Rocky Mountain Region (Okanogan Highlands):

    • Small population with limited economic opportunities.
    • Industries: Mining and tourism.
    • Tourist town: Winthrop.
3. Bodies of Water

  • Rivers:

    • Columbia River: Flows from northeast to south.
    • Spokane River: Runs through Spokane.
    • Snake River: Located in the southeast.
    • Yakima River: Flows from the Cascades into the Columbia.

  • Lakes:

    • Lake Chelan: Central Washington.
    • Lake Washington: Between Seattle and Bellevue.
    • Lake Sammamish: East of Lake Washington.

  • Other Bodies of Water:

    • Strait of Juan de Fuca: Northern Coastal Region.
    • Pacific Ocean: Western boundary of the state.
    • Puget Sound: Significant salt-water body with multiple ports.
4. Mountains

  • Mountain Ranges:

    • Olympic Mountains: Northern Coastal Region.
    • Cascade Mountains: Central Washington, volcanic range.
    • Blue Mountains: Southeast corner by Walla Walla.

  • Volcanic Peaks:

    • Mt. Baker: Northern-most volcanic peak.
    • Glacier Peak: In the North Cascades.
    • Mt. Rainier: Outside Tacoma, central location.
    • Mt. Adams: South Cascades.
    • Mt. St Helens: South Cascades, west of Mt. Adams.
5. Cities and Towns

  • Coastal Region:

    • Port Angeles, Forks, Aberdeen.

  • Cascade Mountain Region:

    • Leavenworth (tourist town).

  • Rocky Mountain Region:

    • Winthrop (tourist town).

  • Columbia Plateau Region:

    • Spokane, Pullman, Walla Walla, Yakima, Ellensburg, Wenatchee, Moses Lake.

  • Puget Sound Lowlands:

    • Towns along I-5: Bellingham, Mt Vernon, Everett, Seattle, Tacoma, Olympia, Vancouver.
    • Cities along I-90: Bellevue, Issaquah.
6. Boundaries and Borders

  • Definitions:

    • Boundary: A line defining area limits.
    • Border: To be adjacent or next to.

  • State Boundaries:

    • North: 49th Parallel North (latitude).
    • East: 117th Meridian West (longitude).
    • South: Columbia River.
    • West: Pacific Ocean.

  • Entities Bordering Washington:

    • North: Canada.
    • East: Idaho.
    • South: Oregon.
    • West: Pacific Ocean.
7. Importance of the Columbia River
  • Most powerful river in North America; significant hydroelectric power.
  • Over a dozen hydroelectric dams; dubbed “Engineered River.”
  • Provides irrigation transforming Columbia Plateau into productive farmland.
  • Popular for recreational activities (boating, fishing, etc.).
8. The Rain Shadow Effect
  • Creates wet environments on the windward side of mountains and dry areas on the leeward side.
  • Requires: large body of water, wind, mountain range.
9. Geological Formation
  • Scablands: Formed by Ice Age flash floods.
  • Columbia Plateau: Created by volcanic eruptions.
  • Puget Sound Lowlands: Shaped by glacial activity.
  • North Cascades: Geologically distinct due to unique fossils, rocks, and history with Asia.
10. The Ring of Fire
  • Area of high tectonic activity (volcanic eruptions and earthquakes) around the Pacific Ocean.
11. Mt St Helens Eruption
  • Date: May 18, 1980.
  • Impact:
    • Loss of over 1,000 feet of mountain height.
    • Extensive loss of life and ecological devastation.
    • Significant disruption to local infrastructure due to ash and debris.