This morning we had a “light” earthquake of 4.6 on the Richter scale that was centered about 23 miles from our house. It shook the house pretty good for about 5 seconds. I stayed at my desk and continued working. Not a big deal.

If one has ever been in a high 6 or 7+ earthquake they know the power nature can unleash. I have been close to the epicenter of several 6’s and one 7.1 quake. These definitely get your attention. Most of these large quakes happened at night when I was asleep and were accompanied by power outages. Waking up at night and losing power in an earthquake is a daunting experience.

Most long time residents in California have learned to live with quakes, just as people who live in areas frequented by tornadoes and hurricanes learn to live with those. I think the big difference is the infrequency of earthquakes and the lack of any warning; whereas tornadoes are sometimes predicted ahead of time and hurricanes usually are predicted days in advance.

I have lived in my frame and stucco house since 1979. There are a few minor cracks in the stucco from the 1986 North Palm Springs quake, which was centered about 7 miles from our house (measured 6.0) and the fence posts in the back yard were lifted about 1 to 3 inches each.

Richter Scale

Earthquakes are measured by the USGS using the Richter Scale. This is a log base 10 scale; meaning that a 5.0 quake has a shaking amplitude that is 10 times stronger than a 4.0, and a 6.0 is 100 times stronger than a 4.0 quake. I have built a table (see below) that classifies earthquakes.