Science Spotlight

Station P472

Researcher: Diego Melgar
Scripps Institution of Oceanography, U.C.S.D.

I am most interested in how to respond quickly when large earthquakes happen.

P472, northeast of San Diego, serves as a reference station for earthquake engineering experiments.

State: CA
Country: United States
Elevation: 137.9 m
Lat/Long:  32.8892 / -117.1047

Earthquake Engineering

P472 is located less than a mile from the world's largest outdoor shake table, operated by the University of California San Diego, where real-life, to-scale buildings are built and tested. We use P472 as a reference for all the tests on the shake table that involve GPS. Using the site as a "base station" allows us to collect very accurate measurements of how the buildings tested on the shake table behave. Many of the tests conducted at the shake table have a direct impact on the rules and regulations regarding the way we build buildings in California, and GPS measurements on the buildings are an important part of that.

Learn more about the shake table project through the project website.

Follow Diego Melgar's thoughts about earthquakes, in Spanish, at his blog Develando las geociencias.

Check out this video (mp4 format) and GPS data video (mpg format). The second video shows the motion of a GPS station on the roof of the building versus the one at the base.

Figure 1. A life-size, fully furnished building on top of the world's largest shake table. A shake table simulates the shaking caused by an earthquake. This building is made out of two different materials. This allows us to observe how the shaking affects the materials differently.


Figure 2. GPS instruments are mounted on the corners of the building, on the roof, and at the base of the building to measure shaking. Scientists look at how these GPS instruments move relative to P472, which is a few hundred meters away from the shake table.

Spotlight Questions

  • What is the purpose of a "base station"?

Last modified: 2019-12-26  16:24:52  America/Denver  


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