# In your opinion, what are the odds that a real big earthquake will happen soon? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [April 13, 2014, 5:35pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024 "2014-04-13T17:35:28Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [April 16, 2014, 5:43pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/21 "2014-04-16T17:43:59Z")
> [@The\_Holdsworth\_Effect](#): > > Thanks, Charlie Wayne. The 2001 Rattle in Seattle was a wakeup call- my daughter was at the Pacific science center, and the place was evacuated. She said the earthworms were coming up out of the ground like crazy. My husband was in his shop, and thought he was having heart attack. The 3 equines gathered in the center of their pasture, nose to nose, and the dogs were berserk. Our slate floor cracked a little. We keep supplies, now, but scattered rather than centralized, as if one pace is collapsed, another might be spared. I was at work, and had just finished an exam. I watched the store windows next door wave like a cloth curtain. I still don’t understand why they didn’t shatter;). It’s still the Best Place to live… I’ll just say that it might have been a wake up call, but many people are not getting the message. My wife worked for a school who took until 2005 to make any changes in response to that earthquake, and their solution was to buy extra cell phones. A Superbowl parade was enough to take down cell service in Seattle… do they really think that’s a solution in a serious earthquake? And that was not the only laughable part of their earthquake preparedness. (For example, their disaster plans actually prioritized recovering dead bodies from rubble over erecting shelters for the survivors. Because we all know that middle school students should be out in the rain looking for their dead friends in a collapsed building.) ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [April 16, 2014, 6:50pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/22 "2014-04-16T18:50:25Z")
> [@PurpleClogs](#): > > Not necessarily this month, but the US is due for a big one, yes. Worrisome to me is the one that took place in Idaho this week. Too close to The caldera of Yellowstone. The earthquakes in the Challis area have nothing to do with Yellowstone. What would make us potentially worried about volcanic activity there would be swarms of low-magnitude quakes centered around the magma chamber, not fairly shallow ones hundreds of miles away. The Challis earthquakes (both this recent one and the huge 1983 one) are part of the Intermountain Seismic Belt, which is the result of the the western US being under tension. The Challis valley is one of the northernmost of the Basin and Range valleys, and the earthquakes there are the result of the valley floor dropping relative to the adjacent mountain ranges. Unlike the relatively deep earthquake we’d have to worry about for Yellowstone, the fault that moved in the '83 earthquake is right at the surface and left a cool scarp: [http://www.idahogeology.org/DrawOnePage.asp?PageID=199](http://www.idahogeology.org/DrawOnePage.asp?PageID=199) Although, on the topic of the OP and speaking of the Intermountain Seismic Belt, the Wasatch Front by Salt Lake City is another one of these basin and range faults that is known to have powerful earthquakes. ---
**Author:** ![Diceman](https://avatars.discourse-cdn.com/v4/letter/d/22d042/32.png) [@Diceman](https://boards.straightdope.com/u/Diceman)\ **Post date:** [April 16, 2014, 6:51pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/23 "2014-04-16T18:51:48Z")
This reminds me of something I’ve wondered about. Let’s say that a major earthquake (8.5+) ocurrs directly under Los Angeles. How devastating would that be? ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [April 16, 2014, 6:56pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/24 "2014-04-16T18:56:46Z")
Oh, but also more generally, no there haven’t been more earthquakes lately. You just hear about them more. In the past, you would have heard about an earthquake overseas only if there was significant damage or loss of life, but given the 24 hour news cycle (and the fact that the USGS’s seismograph network is on the internet and generates automatic alerts) they’re more likely to get a passing mention on the US news these days. ---
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [April 16, 2014, 7:01pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/25 "2014-04-16T19:01:41Z")
Most buildings would have some danger of collapsing, which means that many would collapse. Elevated freeway sections would collapse, much like the Loma Prieta quake in the 80’s. Water & gas mains would probably rupture, resulting in loss of service as well as fire danger and inability to douse same. Remember, San Francisco was levelled in the 1906 quake because everybody’s kitchen stove fell over, spilled coals on the floor, fire broke out, and there was no water to fight the fires with. There has been some extensive upgrading of quake-proofing since the last few big quakes down there, but any building which _hasn’t_ gotten upgraded would be at a fairly serious risk in a major earthquake. ---
**Author:** ![Ellen\_Cherry](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ellen_cherry/32/3600_2.png) [@Ellen\_Cherry](https://boards.straightdope.com/u/Ellen_Cherry)\ **Post date:** [April 16, 2014, 7:16pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/26 "2014-04-16T19:16:52Z")
> [@Charlie\_Wayne](#): > > I posted this thread two days ago and today I see in The Drudge Report the following headline: > > **Hundreds of earthquakes strike central Idaho, rattling nerves** > > [Yahoo News: Latest and Breaking News, Headlines, Live Updates, and More](http://news.yahoo.com/hundreds-earthquakes-strike-central-idaho-rattling-nerves-012504416.html;_ylt=AwrTWVU97E1ThGgAM6LQtDMD) > > Hundreds of earthquakes? What the heck is going on? Here is the complete story: > > SALMON, Idaho (Reuters) - Hundreds of low-level and medium-sized earthquakes have struck central Idaho since last month, puzzling geologists who wonder whether the ruptures portend a much larger temblor to come or are merely the rumblings of a seismic fault previously thought to be dormant. > > The recent earthquake swarm, beginning on March 24 and climaxed by a 4.9 magnitude tremor on Saturday, has produced no reports of injuries or severe damage but has rattled nerves in a region where Idaho’s most powerful known quake, measured at 6.9, killed two children in 1983. > > Saturday’s earthquake was the strongest recorded in the state since 2005 and was followed on Monday by a magnitude 4.4 event that struck 10 miles north of the small ranching community of Challis, Idaho, according to the U.S. Geological Survey. Please post only a portion of copyrighted work, with a link, per the [Registration Agreement](http://boards.straightdope.com/sdmb/showpost.php?p=15034592&postcount=1): > [@](#): > > You agree not to post any copyrighted material unless the copyright is owned by you or by the operator of the SDMB, except as permitted by the “fair use” provisions of the U.S. copyright laws (in general this means brief excerpts only). ---
**Author:** ![BrotherCadfael](https://avatars.discourse-cdn.com/v4/letter/b/977dab/32.png) [@BrotherCadfael](https://boards.straightdope.com/u/BrotherCadfael)\ **Post date:** [April 16, 2014, 7:41pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/27 "2014-04-16T19:41:15Z")
100%, for some values of “soon”. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [April 16, 2014, 7:49pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/28 "2014-04-16T19:49:04Z")
I live just a few blocks from the Hayward Fault - in fact they dug a hole in our park to let people see it, and a curb in the parking lot is split due to the motion of the fault. Besides water and food, it is good to have a way of shutting off the gas. We have a gas wrench attached to the shutoff valve so it will be available. But you can never tell. The first earthquake I ever felt was in the middle of Illinois. ---
**Author:** ![Icarus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/icarus/32/72_2.png) [@Icarus](https://boards.straightdope.com/u/Icarus)\ **Post date:** [April 16, 2014, 7:52pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/29 "2014-04-16T19:52:58Z")
> [@Diceman](#): > > This reminds me of something I’ve wondered about. Let’s say that a major earthquake (8.5+) ocurrs directly under Los Angeles. How devastating would that be? There are many factors that determine the damage, not just Richter number. There is the depth of the quake, is it a jolt or a roll, the wave pattern, etc. Even in a large metro area, the real impact gets somewhat isolated. Buildings will fall right there along the faultline, and 2 blocks away it’s just shake-n-bake. It’s not like everything for 20 miles is flattened. When the Northridge quake hit, I seem to recall it was a jolt. Based on how things like cabinets and shelves fell over you could tell which direction it was traveling. The property damage was centered to the epicenter, and also curiously there was a pocket of damage in Santa Monica 20 miles away. ---
**Author:** ![Icarus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/icarus/32/72_2.png) [@Icarus](https://boards.straightdope.com/u/Icarus)\ **Post date:** [April 16, 2014, 7:56pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/30 "2014-04-16T19:56:07Z")
> [@Voyager](#): > > Besides water and food, it is good to have a way of shutting off the gas. We have a gas wrench attached to the shutoff valve so it will be available. Where we are they installed a tip-over turnoff on everyone’s gas line. There is some dispute about this. The worry is that quake will be strong enough to turn off everyone’s gas, but not really big enough to cause damage. And then everyone (all 7 million) will be calling to get someone out to turn their gas back on! ---
**Author:** ![HeyHomie](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heyhomie/32/207_2.png) [@HeyHomie](https://boards.straightdope.com/u/HeyHomie)\ **Post date:** [April 17, 2014, 6:56pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/31 "2014-04-17T18:56:03Z")
Odds of a major earthquake happening somewhere in the world before the end of the month: almost a certainty. Odds of an earthquake major enough to make world history (like the Indian Ocean Tsunami), cause tens of thousands of deaths, etc., happening before the end of the month: 1 in 1,000. Odds of a devastating earthquake (think: Loma Prieta or Norridge) hitting a major metro area in the U.S. before the end of the month: 1 in 50 maybe? ---
**Author:** ![buddha\_david](https://avatars.discourse-cdn.com/v4/letter/b/ee7513/32.png) [@buddha\_david](https://boards.straightdope.com/u/buddha_david)\ **Post date:** [April 17, 2014, 8:12pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/32 "2014-04-17T20:12:56Z")
> [@HeyHomie](#): > > Odds of an earthquake major enough to make world history (like the Indian Ocean Tsunami), cause tens of thousands of deaths, etc., happening before the end of the month: 1 in 1,000. Think the odds are significantly higher than that, considering we’ve experienced a historically catastrophic earthquake on average every five years (Indonesia '04, Haiti '10, Japan '11, etc.) ---
**Author:** ![Finagle](https://avatars.discourse-cdn.com/v4/letter/f/b19c9b/32.png) [@Finagle](https://boards.straightdope.com/u/Finagle)\ **Post date:** [April 17, 2014, 8:23pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/33 "2014-04-17T20:23:29Z")
> [@HeyHomie](#): > > Odds of a major earthquake happening somewhere in the world before the end of the month: almost a certainty. > > Odds of an earthquake major enough to make world history (like the Indian Ocean Tsunami), cause tens of thousands of deaths, etc., happening before the end of the month: 1 in 1,000. > > Odds of a devastating earthquake (think: Loma Prieta or Norridge) hitting a major metro area in the U.S. before the end of the month: 1 in 50 maybe? Is there a typo here? Because 1 in 50 seems a lot higher than 1 in 1,000. ---
**Author:** ![HeyHomie](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heyhomie/32/207_2.png) [@HeyHomie](https://boards.straightdope.com/u/HeyHomie)\ **Post date:** [April 17, 2014, 10:50pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/34 "2014-04-17T22:50:05Z")
> [@Finagle](#): > > Is there a typo here? Because 1 in 50 seems a lot higher than 1 in 1,000. I don’t consider Loma Prieta or Norridge “devastating” in the sense that the recent quakes in Haiti and Japan were. ---
**Author:** ![buddha\_david](https://avatars.discourse-cdn.com/v4/letter/b/ee7513/32.png) [@buddha\_david](https://boards.straightdope.com/u/buddha_david)\ **Post date:** [April 17, 2014, 10:52pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/35 "2014-04-17T22:52:49Z")
Nitpicking myself: I meant to say the odds are “lower”, not “higher”. :smack: ---
**Author:** ![GreasyJack](https://avatars.discourse-cdn.com/v4/letter/g/df705f/32.png) [@GreasyJack](https://boards.straightdope.com/u/GreasyJack)\ **Post date:** [April 18, 2014, 2:02am UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/36 "2014-04-18T02:02:53Z")
One thing to consider whilst everyone is calculating away on the back of their envelopes: the basis for Charles Richter’s original research was the observation that there is a fairly close relationship between the intensity and frequency of earthquakes. Just like a 7.0 quake Is 10 times stronger than a 6.0, they tend to occur 10 times less frequently, and so on. Over time, this relationship hasn’t proved to be 100% accurate for every region and of course the moment magnitude scale gives slightly different results, but in general it’s a good approximation of how often to expect strong earthquakes. > [@HeyHomie](#): > > I don’t consider Loma Prieta or Norridge “devastating” in the sense that the recent quakes in Haiti and Japan were. Of course, earthquake intensity isn’t everything. The Haiti earthquake was fairly similar in size to the Loma Prieta and Northridge quakes. Quakes that are relatively minor events in a place with good siesmic building codes can be major catastophies elsewhere. ---
**Author:** ![JackieLikesVariety](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackielikesvariety/32/296_2.png) [@JackieLikesVariety](https://boards.straightdope.com/u/JackieLikesVariety)\ **Post date:** [April 18, 2014, 11:06pm UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/37 "2014-04-18T23:06:50Z")
having recently moved to Oregon I am very interested in this subject! I recently found [this report](https://earthchangesmedia.com/?wysija-page=1&controller=email&action=view&email_id=280&wysijap=subscriptions) but I have no idea how reliable it is - be interested in what people think. it says about a 40% chance of a 8.0 - 9.4 quake in the Cascadian Subduction Zone within 50 years, especially the southern half, Southern California and Northern California (down to about Sacramento) ---
**Author:** ![buddha\_david](https://avatars.discourse-cdn.com/v4/letter/b/ee7513/32.png) [@buddha\_david](https://boards.straightdope.com/u/buddha_david)\ **Post date:** [April 19, 2014, 12:38am UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/38 "2014-04-19T00:38:48Z")
> [@GreasyJack](#): > > Of course, earthquake intensity isn’t everything. The Haiti earthquake was fairly similar in size to the Loma Prieta and Northridge quakes. Quakes that are relatively minor events in a place with good siesmic building codes can be major catastophies elsewhere. Case in point: Just this morning, [a 7.2 struck the Mexican coast](http://www.chicagotribune.com/news/chi-mexico-earthquake-20140418,0,1046254.story), but there’s been no reports of casualties or major damage. ---
**Author:** ![The\_Holdsworth\_Effect](https://avatars.discourse-cdn.com/v4/letter/t/848f3c/32.png) [@The\_Holdsworth\_Effect](https://boards.straightdope.com/u/The_Holdsworth_Effect)\ **Post date:** [April 19, 2014, 8:07am UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/39 "2014-04-19T08:07:15Z")
> [@dracoi](#): > > I’ll just say that it might have been a wake up call, but many people are not getting the message. My wife worked for a school who took until 2005 to make any changes in response to that earthquake, and their solution was to buy extra cell phones. A Superbowl parade was enough to take down cell service in Seattle… do they really think that’s a solution in a serious earthquake? And that was not the only laughable part of their earthquake preparedness. (For example, their disaster plans actually prioritized recovering dead bodies from rubble over erecting shelters for the survivors. Because we all know that middle school students should be out in the rain looking for their dead friends in a collapsed building.) Some hear and prepare, some do not. The above is mind boggling. My biggest fear would be not getting home if a quake happened in the daytime, as the Hood Canal Bridge would likely go down, and I’d bet Liliwaup would slide into the water, along with a good bit of 101 along the Canal. OTOH, I’ve contacts amongst The Swift and Silent;) (though they’d likely have their own issues). Aside from relatively basic preparedness, it’s best not to dwell overly on it. Do be alert for the warnings, whether it be quake, hurricane, tornado, or volcanic eruption. I’ve lived through all except the Volcano, and if Ranier blows, well, I’ve had a good life… ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [April 19, 2014, 10:15am UTC](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024/40 "2014-04-19T10:15:07Z")
> [@The\_Holdsworth\_Effect](#): > > Some hear and prepare, some do not. The above is mind boggling. The idea that people who are “prepared” for an earthquake have some sort of advantage over the unprepared always makes me laugh… “The building just fell over on me. Thank goodness I was prepared for that.” “My neighborhood is on fire. But I was prepared.” “A bridge fell apart as I was driving across. But I was prepared.” “My bugout bag had enough food for 7 days. But my neighbor stole it after we started starving.” etc [Previous page](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024.md?page=1) [Next page](https://boards.straightdope.com/t/in-your-opinion-what-are-the-odds-that-a-real-big-earthquake-will-happen-soon/686024.md?page=3)