Research Areas

1. Fault Zones and Basins in the Urban Corridor
2. Lowland Surface Processes and History
3. Geology of Lowland Aquifers
4. Cascadia Framework and Geospatial Databases
5. Tyee Basin
6. North Cascades
7. Geology of the Olympic Peninsula and Olympic National Park

What's New

• New Geologic Maps

Find Maps

• Geologic
• Geophysical
• Physiographic
• Lifeline

Click on any region to learn about current research in the Pacific Northwest Geologic Mapping and Urban Hazards study area or click here to find maps.

Seattle lies within the Puget-Willamette Lowland, a seismically active region overlying the Cascadia subduction zone.
Photo by R. Wells, USGS.

Pacific Northwest

The Problem

Seattle and Portland lie within the Puget-Willamette Lowland of western Washington and Oregon. This seismically active region overlies the Cascadia subduction zone, a source of damaging earthquakes and volcanic activity. The Lowland is also subject to landslides, depletion of groundwater, and pressure on coastal resources and nearshore habitats.

Our Objective

Produce geologic maps and research needed for the assessment of seismic shaking hazards, landslide potential, liquefaction, groundwater resources, and hydrocarbon potential in the urban corridor.

Research Goals

1. Document structure and history of urban fault zones and basins
2. Document lowland surficial deposits, processes and history
3. Document geology of groundwater aquifers
4. Document the lowland regional tectonic framework
5. Compile results in a uniform, digital earth science database

Cooperators and Collaborators

• Washington Division of Geology and Earth Resources
• Oregon Department of Geology and Mineral Industries
• University of Washington
• Oregon State University
• Portland State University