Science Spotlight

Station P028

Researcher: Anne Sheehan
University of Colorado

I liked math and science, and the outdoors, and geology and geophysics seemed to be a good way to combine those interests.

Site P028 is in the desert of northern New Mexico.

State: NM
Country: United States
Elevation: 1933.1 m
Lat/Long:  36.0317 / -107.9084

Rio Grande Rift

The data from GPS site P028 contribute to our geologic study of the Rio Grande Rift. A continental rift is a place where the Earth's crust is being pulled apart very slowly. We think that is what is happening at the Rio Grande Rift and the GPS signals can be used to determine if that is true. Volcanic activity and earthquake faults are common at rifts, and our study can give us a better idea of how significant these hazards might be in Colorado and New Mexico.

Figure 1. Dr. Sheehan (on right) with a student geophysical field crew at Green Lakes Valley, Colorado. The students were involved with a project to map out subsurface soil layers using seismic techniques.

Figure 3.The Rio Grande Rift as seen from space. Can you identify it? Do you see a depression, where it looks like the crust has pulled apart? Hint: Look for the Rio Grande River. (Photo: NASA)

Figure 5. The Rio Grande GPS network stretches from northern Colorado to southern New Mexico. Each green square is a GPS site.


Figure 2. Two possibilities for how the Rio Grande Rift is opening. (Credit: Nicolle Rager, NSF)

Figure 4. Position changes for P028 in a North America fixed reference frame. (For help interpreting the graphs, see the GPS Data page.)

Spotlight Questions

  • What is the rate of motion of site P028 relative to the eastern U.S.? Is it moving north-south? East-west? Up or down? By how much?
  • You are a scientist trying to determine whether the Rio Grande Rift is opening. Based on the time series, do you think it is? If so, in what direction? Is this consistent with the topography in Figure 3? If you don't think it's opening, why not?
  • Does the motion of P028 seem fast or slow to you? How does it compare to the motion of other GPS sites?
  • Does the movement of P028 change over time? Is there a pattern to the movement? If so, how frequently does the pattern repeat? What are some possible causes of this motion, based on what you've learned by looking at other GPS sites on this website?

Last modified: 2019-12-26  16:24:53  America/Denver  


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