The Berkeley Seismological Laboratory conducts essential research on earthquakes and solid earth processes while collecting and delivering high quality geophysical data.
The Cascadia Subduction Zone (CSZ) "megathrust" fault is a 1,000 km long dipping fault that stretches from Northern Vancouver Island to Cape Mendocino California. It separates the Juan de Fuca and North America plates. New Juan de Fuca plate is created offshore along the Juan de Fuca ridge. The Juan de Fuca plate moves toward, and eventually is shoved beneath, the continent (North American plate).
Cascadia Earthquake Sources
Compared to what we know about earthquake hazards in California, less is known in the Central US. The main reason for this difference is the relatively few numbers of large earthquakes in the Central US compared to California. The more frequent occurrence of small and larger earthquakes in California gives scientists data that can be used to infer the effects of historical earthquakes in the region and estimate the effects of future large earthquakes. A lack of large earthquakes in the Central US means a lack of data on stronger ground motions from big earthquakes. When there is little observational data, scientists use models to generate estimated data. A model for estimating the effects of an earthquake includes an earthquake source and the earth through which the seismic waves travel. A research paper on this modeling effort (4.7MB PDF) was published in the August 2015 issue of the Bulletin of the Seismological Society of America.
Model overview. The regional structure is constructed by extending the physical properties of most of the well-defined units to less well-constrained areas in the Mississippi Embayment and the CUS: Paleozoic, Crystalline Upper Crust, Lower Crust, Modified Lower Crust and Upper Mantle. The Mesozoic to Cenozoic materials are represented by several units within the Mississippi Embayment and a Vs30 based layer outside the embayment.
The Seismology Working Group promotes and informs the development of open source seismic wave propagation codes in support of seismic source and structure studies, as well as cross-cutting investigations in natural hazards, resource assessments, and planetary geophysics. Seismology codes support both research and learning using a broad range of computing architectures. We aim to anticipate trends in computing and data in order to advance scientific discovery. We welcome feedback from the entire seismological community.
Computational Infrastructure for Geodynamics (CIG) is a community-driven organization that advances Earth science by developing and disseminating software for geophysics and related fields.