Newswise — The earthquake swarm that hit southeastern Idaho in the last several days could be concerning both not only to the affected region but also to other parts of the western United States that are on fault lines that could extend and cause similar ruptures and the resultant tremors.

Ryan Porter, an assistant professor of geology at Northern Arizona University, is available to discuss this earthquake swarm and its significance for the region. His research looks at using earthquake seismology, specifically in using earthquake seismic waves to study the subsurface and better understand plate tectonics. His specialty area is the North and South American Cordillera.

CONTACT: Ryan Porter, assistant professor of geology, Northern Arizona University, (928) 523-2429 or [email protected]

 Talking points

  • That area is part of the Basin and Range province, which is actively extending. Many of the earthquakes being felt are likely aftershocks from the magnitude 5.3 quake on Sept. 2 and are part of the crust accommodating that extension.
  • This interpretation is based on looking at focal mechanisms from the earthquakes, which are ways that seismologists can see how the earth ruptured. Regional extension along faults causes the topography to appear as a series of high mountain ranges separated by sediment-filled basins across much of Nevada, southeastern California, southern Arizona and southern Idaho.