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Pacific Northwest Geologic Mapping and Urban Hazards

Cascadia framework and regional databases

The plate tectonic framework and large-scale crustal structure of the Cascadia convergent margin provides the context for understanding the present distribution of earthquakes, volcanoes, and young deformation in the Pacific Northwest. Our research is focused on four major themes:

Cascadia plate motions and forearc migration

Cascadia plate motions and forearc migration

Northward migration of the Cascadia forearc along the coast at about 10mm/yr affects the behavior the subduction zone megathrust and causes earthquakes in the urban corridor. Synthesis of the geology provides constraints on the relationship between great subduction zone earthquakes, long term forearc deformation and upper plate seismicity.
Comparing Cascadia to other subduction zones

Comparing Cascadia to other subduction zones

In many circum-Pacific subduction zones, forearc basins seem to correlate with seismically and geodetically determined asperities (concentrations of seismic slip) during great earthquakes. Cascadia's offshore basin geometry may provide clues to the long-term release of seismic energy along the margin.
Cascadia crustal structure and seismicity

Cascadia crustal structure and seismicity

Geologic and geophysical mapping of crustal structure in the forearc provides a framework for understanding the distribution of earthquakes and their kinematics in the urban corridor.
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Cascadia and the global timescale

High-resolution ages of earth materials allow us to determine the rate of geologic processes (e.g., deformation, sedimentation), the timing of past geologic events (e.g. earthquakes), and the relationship among events across broad geographic areas (e.g., earthquakes and volcanism).

Magnetostratigraphy, paleomagnetic correlation, and deformation of Pleistocene deposits in the south-central Puget Lowland

Related Pacific Northwest Urban Corridor Geologic Mapping Project publications

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