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some interesting information about earthquakes out west and what may happen in the future:

Anderson said the Earth’s core is very hot and is cooling. As it cools, it causes the upper 60 miles of the Earth’s crust to shift and the movement is generally in pieces of the crust called tectonic plates. At the famous San Andreas fault, the plate that makes up the floor of the Pacific Ocean is grinding against the plate that makes up California as the Pacific plate moves toward the northwest United States at a rate of about 2 inches a year. That grinding causes earthquakes all the way into Nevada, he said.

Another factor is the expansion on the east side of the Sierra. About 20 million years ago, the Great Basin began expanding. Since the expansion started, the distance between the California border and the Utah border roughly doubled, Anderson said.
As Nevada expanded, its mountains became taller and its valleys deeper, he said.
“In one sense, this is good,” Anderson said. “We owe all our mountains to this extension. I like the mountain ranges here and I’m sure a lot of people do.
“These mountain ranges were all built one earthquake at a time.”
Before 1915, the last major quake in the Reno area that was a magnitude 7 was probably in 1860, Anderson said.

About 600 years ago and about 1,900 years ago there were magnitude 7 quakes along the east side of Mount Rose, he said.