Probabilities of Earthquakes of Various Magnitudes Occurring within 50 Years within 50 Kilometers of Major Communities in Nevada

The table below shows the probability of experiencing an earthquake of a given size or greater over a 50-year period within 50 kilometers (31miles) of major communities in Nevada, and the maps linked with this table are intended to give people throughout Nevada an idea of their earthquake risk. These maps were generated for four magnitude thresholds: M≥5.0, M≥6.0, M≥6.5, and M≥7.0 using the U.S. Geological Survey PSHA (Probabilistic Seismic Hazard Analysis) Model, which is presented at http://earthquake.usgs.gov/hazards/apps/.

What these Magnitudes Mean

Although it is nearly impossible to specifically predict what an earthquake of a given size might do to a community, the earthquake sizes presented relate to different general levels of damage. Generally, the greater the magnitude, the stronger the shaking will be and the longer the shaking will last.

Magnitude 5 earthquakes are distinctly felt by almost everybody and can cause rockslides and nonstructural damage, such as heavy, unsecured objects falling off shelves.

Magnitude 6 earthquakes can cause significant nonstructural damage, especially in basins and along ridge tops.

Magnitude 6.5 earthquakes can create surface offsets, may be of longer duration, and can cause significant damage.

Magnitude 7 earthquakes cause widespread structural and nonstructural damage, and require a significant “recovery period” for communities to get back to get back to the way they were before the quake.

The Maps

Each map covers an area of about 120 kilometers (75 miles) around the indicated community. The numbers along the left side of the map are degrees and minutes north latitude, and the numbers along the bottom are degrees and minutes west longitude.

The numbers on the probability scales indicate the probability of an earthquake equaling or exceeding the given magnitude within 50 kilometers (31 miles) of  the given location within the next  50 years. The numbers on the scale can be converted to percentage by multiplying by 100; for example. “0.10” is 10%. The colors indicate the ranges of probability and run from light blue for low probability to red for high probability to brown for maximum probability. Note: Each map has its own probability scale and color scheme.

There are many uncertainties in the input data for these calculations, but they are based on the best data available. It is important to keep this in mind in some of the lower probability areas of Nevada.  Low probability doesn’t mean that an earthquake won’t occur. Earthquake sources are located throughout the state, and earthquakes have been known to occur in areas where the probabilities were low. All of Nevada is earthquake country, and mitigating for safety and to protect valuables is a good idea everywhere. The maps are meant to be general guides to earthquake potential for communities in Nevada, at the current state of knowledge.

Click on the numbers in the cells to display the earthquake probability maps.