Seismic Hazard in the Reno Area

I had completely forgotten about this blog. But I accidentally rediscovered it, and actually have something that might be worth posting. If anyone reads it, maybe I'll post some more.

A friend who also is a real estate agent asked me the following questions:

Question 1. What is the seismic hazard in the Reno area?
Question 2. Where are the main faults and how active are they?
Question 3. Should a home buyer avoid buying a home, or a lot, close to an active fault?

I will give my answer to the first question here.

Question 1 may be answered by the National Seismic Hazard Maps that have been produced by the U. S. Geological Survey. Details are on their web site: https://earthquake.usgs.gov/hazards/  

One of the USGS maps is shown in Figure 1. What I notice is that in the area near Reno – Carson City, there is a little red sliver of hazard that is the same color as along the major faults of California to the west. It turns out that the red sliver coincides with the urban area from Reno to Gardnerville. So there is an earthquake hazard in the populated areas of western Nevada, and it is rather high.

Not all red areas on this map are the same.  The map uses distinctive colors for different ranges of the hazard. The hazard is not as high in Reno as it is along the major California faults, but it edges into that range. What I tell people is that if one of the faults in Reno breaks, the ground shaking will be as strong as it would be if a similar fault breaks in California. The difference, and the reason our hazard is a little lower, is that the faults here do not break as often as the major California faults. 

Be prepared. Visit the Nevada Seismological Laboratory web site for more details.

http://www.seismo.unr.edu/Preparedness

Figure 1. National seismic hazard map (2014) for the United States. This image was found on the USGS web site on August 7, 2017: ftp://hazards.cr.usgs.gov/web/nshm/conterminous/2014/2014pga2pct.pdf

This map is developed for a standard soil condition, known in technical terms as “Vs30=760 m/s”.  In lay terms, this represents soft rock.