# What are the chances of Orange County being hit with a big earthquake?

I recently moved to southern california. I have been watching the news and they keep saying that we are due for "the big one." I am really nervouse about this. We had a 4.4 the other day and that was scary enough. Have there ever been any big earthquakes out here? I do not even know what they really feel like, except for the one from last week, but I barely woke up for that.

 cdad Posts: 11,115, Reputation: 6615 Internet Research Expert #2 Mar 23, 2010, 02:47 PM
If your going to live in that area then you have some reading to catch up on. There are a lot of earthquakes in that area. In general anything above 5.4 can caus minor damage. So if you live in earthquake country just be prepared. Make sure cabinets are secured to walls with brackets etc. Have an escape route planned just like you would for fire. Each tenth of an increase is a value of 100 times stronger on the richter scale. Just enjoy them like disneyland.
 ebaines Posts: 10,136, Reputation: 5589 Expert #3 Mar 26, 2010, 07:06 AM
Quote:
 Originally Posted by califdadof3 Each tenth of an increase is a value of 100 times stronger on the richter scale.
Tthe Richter scale is a base-10 logarithmic scale, where the difference in energy between any two levels ($\Delta D$) is:

$
\Delta E = (10^{\Delta D}) ^ {3/2}
$

So the difference in energy for a full step in the Richter scale is

$
\Delta E = 10^{3/2} = 31.6
$

And for a 1/10 step the increase is:
$
\Delta E = (10^{0.1})^{3/2} = 1.412
$

The important part to remember is that a magnitude 6 quake is a lot more powerful than a magnitude 5.
 FlyYakker Posts: 378, Reputation: 204 Full Member #4 Mar 28, 2010, 05:49 PM
At any rate here is a map giving you an idea of what is going on where in CA. Maps of Recent Earthquake Activity in California-Nevada

 justcurious55 Posts: 4,361, Reputation: 4033 Ultra Member #5 Mar 28, 2010, 05:59 PM
I live in so cal too. I didn't even feel the one the other day. I seem to be the only one who slept through it...

You should also know where your gas and water valves are and how to shut them off. My last landlord made sure I knew how to do it in case anything happened and he wasn't there. Your post reminds me I really should learn where they are in my new place.
 cdad Posts: 11,115, Reputation: 6615 Internet Research Expert #6 Mar 28, 2010, 07:22 PM
Quote:
 Originally Posted by justcurious55 i live in so cal too. I didn't even feel the one the other day. I seem to be the only one who slept through it... You should also know where your gas and water valves are and how to shut them off. My last landlord made sure I knew how to do it in case anything happened and he wasn't there. Your post reminds me I really should learn where they are in my new place.
Also don't forget having the right tools at hand to be able to do it. Like a T-handle for water mains and a wrench for the gas line.
Also its a good idea to have / store emergency supplies outside the home if you can like in a shed. At least the basics and some blankets.
 vince007 Posts: 3, Reputation: -1 Junior Member #7 Sep 12, 2011, 10:19 PM
Welcome to southern California. The region experiences large magnitude earthquakes about every 20 years - large being 6 to 7.3. These are scary to be in if you are close to the epicenter, say, within 50 miles. Close by, the nearest large faults are the Elsinore and San Jacinto, as well as some offshore. The San Andreas fault is the "big one" that the Cal Tech and USGS scientists like to talk about, but its magnitude potential is often overstated (7.3 magnitude max). Besides, it is quite a ways from you - you will feel it, but at a distance. The major problem I would be concerned with would be food, water and comfort in a region of 12 million people that are having some shortages. Not surprisingly, many people are injured by aftershocks, which can be weeks later, but significant events of 5 or 6 magnitude, shaking already weakened buildings.

PS. When a big one shakes, you will not be able to stand, walk or move during the event, so forget all that advice about getting in a doorway or under a table or whatever.
 cdad Posts: 11,115, Reputation: 6615 Internet Research Expert #8 Sep 13, 2011, 02:40 AM
Quote:
 Originally Posted by vince007 PS. When a big one shakes, you will not be able to stand, walk or move during the event, so forget all that advice about getting in a doorway or under a table or whatever.
You can move in a quake. Where it can come as a surprise is when the quake can either be horizontal or vertical. @ very different types of movement. But you most certainly can move. In the beginning most quakes start light then intensify. Giving you time to move away from windows if needed.