Nevada’s Most Powerful Earthquake Ever Was a Real World-Shaker

Nevada has a high incidence rate of earthquakes compared to other states. Unlike some states that experience somewhat weak and infrequent earthquakes, the ones that strike the Battle Born State can be very powerful. Learn about Nevada’s most powerful earthquake ever and find out how strong it was, when it occurred, where it struck, and the damage it caused. Find out everything you need to know about this event!

What Was Nevada’s Most Powerful Earthquake?

Nevada’s most powerful earthquake ever was a 7.3 M_w quake that struck on October 2, 1915. The earthquake is often referred to as the 1915 Pleasant Valley Earthquake. According to the University of Nevada, the earthquake was the largest in the state’s recorded history with an overall 7.3 magnitude.

However, not all sources agree on the quake’s magnitude. Some sources say that the moment magnitude (M_w) was 6.8 but the surface-wave magnitude (M_s) reached 7.7. Although sources may disagree on the earthquake’s magnitude, the quake was very large and potent.

Pershing County experienced many foreshocks leading to the main event. The foreshocks leading to the mainshock were unusually powerful, ranging between 5.1 and 6.1 M_w. The foreshocks struck between 1 p.m. and 5:50 p.m. and grew with intensity throughout the day. Witnesses said the ground rumbled, animals grew nervous, and trees swayed during such events. 

The mainshock struck at about 10:54 p.m. on October 2, 1915. According to witnesses, the quake threw people from their beds and tossed them all over for several minutes. The shaking was very intense, and the quake was felt throughout the state and into California, Oregon, Idaho, and Utah. In fact, the intensity measured X (Extreme) on the Modified Mercalli intensity scale. That is the third-highest designation on the scale. Such quakes can destroy wooden structures, bend railroads, and cause significant landslides.

What Type of Fault Caused the 1915 Pleasant Valley Earthquake?

Scientists did not identify the specific fault or fault type that caused Nevada’s most powerful earthquake. However, they believe that the quake originated about 6 miles below the earth’s surface. The quake left behind many signs of vertical displacement in the form of fault scarps. In this case, four long scarps formed during the quake, measuring a total of almost 40 miles.

On average, the ground’s vertical displacement in the most affected areas reached almost 7 feet, but the greatest displacement was about 20 feet in eastern Pleasant Valley. Although this quake is not known for causing a massive number of casualties, the impact it had on the land near the fault is simply incredible.

Where Was the Epicenter of Nevada’s Most Powerful Earthquake Ever?

Officially, the epicenter was at 40.26°N 117.65°W, so the quake’s epicenter was in Pershing County. The damage from the quake extended about 50 miles in all directions from that point. The quake was felt over a large area, including several nearby states. 

Fortunately, the quake’s epicenter was in an area with a relatively low population. As a result, the injuries, damages, and deaths were minimal. 

How Much Damage Did the Quake Cause?

The earthquake caused a fair amount of damage despite occurring in a somewhat desolate region. A few homes made from adobe collapsed outright. Several ranches sustained severe damage, chimneys collapsed, and some buildings were shifted off of their foundations. People reported being shaken out of their beds at night.

After the earthquake subsided, the states experienced several aftershocks. While they were not as powerful as the foreshocks, they contributed to the mental distress felt by those who suffered from the main shock.

No monetary figures exist about the amount of damage caused by the quake. Based on the available evidence, the event damaged relatively few structures.

The Casualties from Nevada’s Most Powerful Earthquake

Despite moderate, widespread damage throughout Nevada, the earthquake did not cause any casualties. At least, no deaths or injuries were recorded and made widely available in newspapers. So, despite the 1915 Pleasant Valley earthquake being Nevada’s most powerful earthquake, nobody died as a result of it. The lack of highly populated areas near the epicenter contributed to this lack of injuries and deaths.

If an earthquake with the same magnitude struck a more populated area these days, it would likely cause some injuries and deaths. Still, many modern structures are built with the possibility of strong earthquakes in mind. Some buildings feature structural designs that will allow them to withstand quakes to some degree.

All in all, Nevada’s most powerful earthquake affected a large but relatively uninhabited area. Given the high number of quakes that strike the area and the state’s increasing population, residents in earthquake-prone areas must have safe structures and the knowledge of how to react during a quake. That way, future quakes will continue to have a low cost in terms of lives and infrastructure.  

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