WEBVTT - The Future of Earthquakes 0:00:00.160 --> 0:00:07.080 Brought to you by Toyota Let's go places. Welcome to 0:00:07.280 --> 0:00:15.720 Forward Thinking, Hi, and welcome to Forward Thinking, the podcast 0:00:15.800 --> 0:00:18.159 that looks at the future and says, I feel the 0:00:18.200 --> 0:00:21.200 Earth move under my feet. I'm Lauren voc Obama, and 0:00:21.320 --> 0:00:24.560 I'm Joe McCormick, and our regular host Jonathan Strickland is 0:00:24.600 --> 0:00:28.600 not with us today as having a beautiful vacation. Yes, 0:00:28.880 --> 0:00:33.200 hopefully not along the fault line anywhere, which introduces today's topic, 0:00:33.280 --> 0:00:37.440 which is earthquakes. We after we did our super volcano episode, 0:00:37.479 --> 0:00:39.920 we received a couple of messages, one from Jacob via 0:00:39.960 --> 0:00:43.160 Twitter and one from Matt via Facebook, who both wrote 0:00:43.159 --> 0:00:48.560 in to request an episode about another big disaster, earthquakes. Yeah, 0:00:48.600 --> 0:00:51.400 and not just about what earthquakes are and how they work, 0:00:51.400 --> 0:00:54.480 of course, but seeing as this is Forward Thinking, what 0:00:54.520 --> 0:00:56.320 are we going to do about them in the future? 0:00:56.360 --> 0:00:59.920 Will we ever be able to predict earthquakes and understand 0:01:00.320 --> 0:01:02.600 what causes them, when and where they're going to happen, 0:01:02.680 --> 0:01:05.560 and how to stop them and protect against them? Oh? Sure? 0:01:05.600 --> 0:01:08.440 And especially that protect protect against them thing, because even 0:01:08.480 --> 0:01:11.720 if we can't predict them, how can we prepare ourselves 0:01:11.760 --> 0:01:14.280 better for them? Sure? And I'm sure One of the 0:01:14.319 --> 0:01:17.559 reasons people want to know about earthquakes right around now 0:01:18.319 --> 0:01:22.280 is the grand trailer for this movie that's out this 0:01:22.319 --> 0:01:25.920 summer called San Andreas. Yeah. Yeah, that came out on 0:01:26.040 --> 0:01:29.920 May nine. I believe it features the rock right. It's 0:01:30.000 --> 0:01:33.200 not a grand theft auto movie. It is a movie 0:01:33.360 --> 0:01:37.240 about a big earthquake, in the tradition of other movies 0:01:37.280 --> 0:01:41.040 about big disasters where stuff falls over. Yeah, lots of 0:01:41.080 --> 0:01:43.840 stuff falls over, as it turns out. I have not 0:01:43.920 --> 0:01:46.360 seen this movie. I'm probably not going to, but I 0:01:46.400 --> 0:01:48.360 gotta be honest. I saw the trailer when I was 0:01:48.360 --> 0:01:52.560 in the theater watching Mad Max Fury Road, and it 0:01:52.640 --> 0:01:55.680 was hilarious. I I have to say that I laughed 0:01:55.680 --> 0:01:58.960 through that entire trailer, and I'm not I feel I 0:01:59.000 --> 0:02:01.279 felt kind of bad out it at the time because 0:02:01.280 --> 0:02:04.320 although I knew that those digital people were fine, like, like, 0:02:04.400 --> 0:02:07.040 no digital people were harmed in the making of those 0:02:07.080 --> 0:02:10.840 digital effects shots. Earthquakes are very serious matters, of course, 0:02:11.240 --> 0:02:15.040 right there are terrifying and unpredictable attack upon our placid 0:02:15.120 --> 0:02:18.560 urban lives and and a lot of times they seem 0:02:18.600 --> 0:02:20.760 to come out of nowhere and they can kill thousands 0:02:20.800 --> 0:02:24.520 of people, and so of course earthquakes are worth understanding 0:02:24.560 --> 0:02:27.600 to figure out, not just for the pure science of it, 0:02:27.680 --> 0:02:30.680 but to save lives. Oh of course. Yeah. And and 0:02:30.800 --> 0:02:33.200 the thing, of course about the ground that we stand 0:02:33.240 --> 0:02:36.840 on is that it is not solid at all. Well, 0:02:36.960 --> 0:02:40.240 I mean, i'd say it is solid, but it's not. 0:02:40.760 --> 0:02:45.680 It's not what stationary should we yes, and not just 0:02:45.720 --> 0:02:49.160 in the way that that planet Earth is like a spaceship, uh, 0:02:49.200 --> 0:02:52.560 that the ground is always moving. Earth's crust is made 0:02:52.639 --> 0:02:56.760 up of continent sized slabs of rock called tectonic plates, 0:02:57.040 --> 0:03:00.520 which are constantly moving and rubbing up again to each other, 0:03:01.000 --> 0:03:04.799 pushing over under one another, or moving slightly apart. And 0:03:05.120 --> 0:03:09.800 that's fine, that's great, that's I don't know if that's fine. Yeah, 0:03:10.080 --> 0:03:12.280 it's fine. Well, it's normally on a day to day basis, 0:03:12.280 --> 0:03:16.560 it's usually fine. Um. But sometimes those those edges, those 0:03:16.600 --> 0:03:20.960 faults can crack or slip against each other abruptly, causing 0:03:21.000 --> 0:03:24.600 these very powerful vibrations to shake the edges of those 0:03:24.600 --> 0:03:27.960 plates in in patterns radiating outward from the point of 0:03:28.000 --> 0:03:32.640 that slippery origin. Um. And those vibrations a k a. 0:03:32.720 --> 0:03:35.960 Seismic waves are what we feel as earthquakes. Yeah, I 0:03:36.000 --> 0:03:38.400 was trying to think of a good analogy for how 0:03:38.440 --> 0:03:41.680 earthquakes are created in a at a scale that we 0:03:41.720 --> 0:03:44.440 can experiment with. And I think this sort of works. 0:03:44.840 --> 0:03:48.480 If you put on some rubber soled shoes and then 0:03:48.600 --> 0:03:52.320 try to walk along on say like a hardwood floor 0:03:52.520 --> 0:03:55.880 or like a basketball gym floor, without lifting your feet, 0:03:55.960 --> 0:03:59.880 just scooting your shoes along, well, you'll probably notice if 0:04:00.080 --> 0:04:02.880 or shoe scooting experiences anything like mine, is that for 0:04:02.920 --> 0:04:05.080 a certain length of the slide, the shoe will move 0:04:05.160 --> 0:04:07.400 kind of smoothly, but every now and then it will 0:04:07.440 --> 0:04:10.520 sort of get caught for a second. The forward momentum 0:04:10.560 --> 0:04:12.960 will briefly pause, and then you'll experience a sort of 0:04:13.080 --> 0:04:18.000 sudden jolt forward, sometimes accompanied by the classic vibratory sounds 0:04:18.040 --> 0:04:23.800 of scooting, scoot, And these vibrations you can think of 0:04:23.800 --> 0:04:26.640 as being kind of analogous to what's happening when these 0:04:26.680 --> 0:04:30.640 plates are scooting against each other. Sure, and and researchers 0:04:30.680 --> 0:04:32.680 think that it's a it's a build up of potential 0:04:32.800 --> 0:04:36.200 energy over periods of time that are not, to our 0:04:36.760 --> 0:04:42.120 knowledge predictable yet. Um, but we'll address that question later 0:04:42.160 --> 0:04:47.320 in this episode. Yes, yes, but but earthquakes happen constantly. 0:04:48.200 --> 0:04:50.560 Oh yeah, yeah. The U S Geological Survey estimates that 0:04:50.640 --> 0:04:54.720 as many as one point three million earthquakes happen every year. 0:04:54.800 --> 0:04:57.440 And that's just the ones that are over a two 0:04:57.480 --> 0:04:59.440 point oh on the Richter scale, which is the point 0:04:59.480 --> 0:05:02.039 at which human can feel them. Right, And then it's 0:05:02.040 --> 0:05:05.960 not even just the primary effects of the vibration of 0:05:06.000 --> 0:05:08.440 the ground of the earthquake, right, Earthquakes have lots of 0:05:08.520 --> 0:05:12.279 secondary causes that can become disasters on their own. Oh, 0:05:12.320 --> 0:05:17.239 of course, there's a tsunami, and avalanches and landslides and liquification, 0:05:17.400 --> 0:05:20.840 which is a thing where solid ground starts acting like 0:05:20.880 --> 0:05:25.479 a liquid which uh, and and flooding and you know, 0:05:25.520 --> 0:05:29.400 the collapse of human made structures and the lack of 0:05:29.520 --> 0:05:34.120 resources and the aftermath that ensues and all of these 0:05:34.520 --> 0:05:37.000 terrible things. Of course. Yeah, So we have very good 0:05:37.000 --> 0:05:39.880 reason to want to understand how earthquakes work and what 0:05:39.960 --> 0:05:41.919 we can do about them. So so I figured we 0:05:41.920 --> 0:05:44.679 should start by going back a little bit and looking 0:05:44.720 --> 0:05:49.520 at how our understanding of earthquakes developed over time. Yeah, yeah, what, 0:05:50.480 --> 0:05:53.400 I bet people had some interesting ideas about earthquakes and 0:05:53.480 --> 0:05:57.120 ancient times. Well, you'd be right. So the ancient world, 0:05:57.120 --> 0:06:00.000 of course, experienced plenty of earthquakes, just as many earthqua 0:06:00.000 --> 0:06:04.240 wakes as we do today, and without the scientific framework 0:06:04.320 --> 0:06:08.479 to explain them, they came up with some pretty weird 0:06:08.760 --> 0:06:15.200 and sometimes funny explanations. So religious spiritual magical explanations were 0:06:15.240 --> 0:06:18.120 extremely common all over the world West and the East. 0:06:18.520 --> 0:06:23.800 People sort of explained earthquakes as often as divine punishments 0:06:23.920 --> 0:06:26.800 or divine im portents. Gods were either like giving a 0:06:26.880 --> 0:06:31.280 warning or were angry and issuing punishment. I found this 0:06:31.360 --> 0:06:36.120 one funny example of both the magical explanations given by 0:06:36.160 --> 0:06:39.600 the ancients and some of the practical explanations. And these 0:06:39.640 --> 0:06:44.279 are chronicled in the writings of the Roman historian Ombianus Marcellinus, 0:06:44.279 --> 0:06:47.200 who is a soldier by trade, and he lived during 0:06:47.240 --> 0:06:51.279 the fourth century CE, and he wrote a surviving history 0:06:51.279 --> 0:06:54.200 at the time, and and he he has a little 0:06:54.240 --> 0:06:57.120 discourse on earthquakes, and what he says is that when 0:06:57.160 --> 0:07:00.880 you're talking about earthquakes, quote, in all priests the ceremonies, 0:07:01.080 --> 0:07:04.839 whether ritual or pontifical, care is taken not at such 0:07:04.880 --> 0:07:08.119 times to name one god more than another, for fear 0:07:08.200 --> 0:07:12.040 of impiety, since it is quite uncertain which God causes 0:07:12.080 --> 0:07:16.200 these visitations. I love it. They didn't want to they 0:07:16.240 --> 0:07:22.680 didn't want to assign blame without all the facts. Well 0:07:22.680 --> 0:07:25.200 that's that's good. I mean, you know, that's covering your bass. 0:07:25.280 --> 0:07:30.880 I approve of the hypothesis format of finding knowledge. Sure, 0:07:31.000 --> 0:07:33.480 and then of course you had sort of spiritual or 0:07:33.520 --> 0:07:37.040 supernatural explanations in in the East as well. So like 0:07:37.080 --> 0:07:40.680 some ancient Chinese explanations seem to have read earthquakes again 0:07:40.720 --> 0:07:44.320 as divine punishments importance. But to continue with what our 0:07:44.400 --> 0:07:49.040 historian Marcellinus had to say, this was great because he 0:07:49.200 --> 0:07:53.480 also chronicled what some of the dominant practical explanations of 0:07:53.480 --> 0:07:55.960 the day were. So it wasn't that everybody just had 0:07:55.960 --> 0:07:59.800 this religious explanation. There were also the ancient natural philosophers 0:07:59.840 --> 0:08:02.800 who were like, no, let's figure this out. Truly, something's 0:08:02.840 --> 0:08:05.240 going on under the earth. I mean, Aristotle surely had 0:08:05.240 --> 0:08:08.640 something to say about it. Oh yes, So quoting again 0:08:08.720 --> 0:08:11.800 from Marcellinus, and all of these quotes from Marcellinus are 0:08:11.840 --> 0:08:16.480 from the seedy Youngae translation in English. But as the 0:08:16.560 --> 0:08:21.880 various opinions among which Aristotle waivers and hesitates suggest earthquakes 0:08:21.920 --> 0:08:25.760 are engendered either in small caverns under the earth because 0:08:25.800 --> 0:08:28.640 of the waters pouring through them with a more rapid 0:08:28.720 --> 0:08:33.440 motion than usual, or, as Anaxagoras affirms, they arise from 0:08:33.440 --> 0:08:36.960 the force of wind penetrating the lower parts of the Earth, 0:08:37.080 --> 0:08:40.560 which when they have got down to the encrusted solid mass, 0:08:40.880 --> 0:08:44.600 finding no vent holes shake those portions in their solid 0:08:44.640 --> 0:08:47.760 state into which they have got entrance when in a 0:08:47.880 --> 0:08:51.719 state of solution. And this is corroborated by the observation 0:08:51.800 --> 0:08:54.600 that at such times no breezes of wind are felt 0:08:54.600 --> 0:08:57.840 by us above the ground, because the winds are occupied 0:08:57.960 --> 0:09:01.600 in the lowest recesses of the earth. Oh that's delightful. 0:09:02.120 --> 0:09:07.160 That is that is so delightfully incorrect. I adore that. Yeah. So, 0:09:07.200 --> 0:09:09.720 I think the idea that was being propagated at the 0:09:09.760 --> 0:09:12.000 time by Aristotle and some of the other well not 0:09:12.080 --> 0:09:15.280 at the time by Aristotle, but had previously been propagated 0:09:15.280 --> 0:09:18.560 by Aristotle and then continued to be believed by many 0:09:18.600 --> 0:09:21.400 people was something having to do with the exchange of 0:09:21.480 --> 0:09:25.679 gases like wind and evaporation under the earth. And sometimes 0:09:25.679 --> 0:09:30.320 when like gases or evaporating uh vapors would get trapped 0:09:30.400 --> 0:09:34.199 under the earth, sometimes they'd be released in a big burst. Sure. Sure, 0:09:34.360 --> 0:09:36.800 Although I suppose it is interesting that they were thinking 0:09:36.880 --> 0:09:41.320 about liquids and the motion that propagates in liquids because 0:09:41.480 --> 0:09:44.800 earthquakes are in fact caused by by waves of energy, 0:09:45.200 --> 0:09:51.120 which at their time was analogous. So analogous, which yes, 0:09:51.320 --> 0:09:54.480 that thing. Yeah, but but I'm sure they probably weren't 0:09:54.559 --> 0:09:57.319 quite thinking yet of the idea of propagation of waves 0:09:57.320 --> 0:10:03.760 through rock, which must have seemed imposs of all So, 0:10:03.880 --> 0:10:09.079 as with many subject areas see cosmology and physics and 0:10:09.120 --> 0:10:13.960 plenty of things, Aristotle's ideas held sway for a long 0:10:14.160 --> 0:10:18.080 long time in Europe and in the Islamic world, despite 0:10:18.080 --> 0:10:21.880 the fact that they were super super wrong. Um Like, 0:10:21.920 --> 0:10:24.360 don't get me wrong about Aristotle. I'm not saying he 0:10:24.400 --> 0:10:26.880 was stupid. He was obviously a super smart guy of 0:10:26.920 --> 0:10:29.760 the ancient world. I guess just everybody must have assumed 0:10:29.800 --> 0:10:35.160 he was right about everything. That's what they did. It's 0:10:35.200 --> 0:10:37.160 kind of funny if if you've never done this, like 0:10:37.280 --> 0:10:43.400 look up what Galileo overthrew about Aristotelian physics, and it'll 0:10:43.440 --> 0:10:45.800 just kind of make you wonder, like, how did people 0:10:45.840 --> 0:10:48.400 miss this for so long? It seemed so easy to 0:10:48.440 --> 0:10:53.480 figure out. But anyway, Aristotle's ideas about earthquakes hell were 0:10:53.600 --> 0:10:56.960 very popular until the early modern period in Europe, and 0:10:56.960 --> 0:11:00.360 then some other physical explanations for earthquakes began to take 0:11:00.360 --> 0:11:06.040 hold in some circles, like explanations involving fire and explosive properties. 0:11:07.280 --> 0:11:10.760 Just one example like what if iron is reacting with 0:11:10.920 --> 0:11:15.119 sulfur deep under the ground and this explosive chemical reaction 0:11:15.280 --> 0:11:19.120 is causing earthquakes? Even kind of makes sense because you 0:11:19.120 --> 0:11:24.200 can see like, okay, earthquakes sometimes or happening around fault lines, 0:11:24.240 --> 0:11:27.520 which they didn't know about then, but but around volcanoes 0:11:28.280 --> 0:11:32.000 they certainly knew about, yeah, bingo, and that volcanoes have 0:11:32.080 --> 0:11:37.040 this explosive fiery element. Eventually, however, we started to get 0:11:37.080 --> 0:11:41.240 some more correct ideas about seismology, and according to a 0:11:41.280 --> 0:11:45.720 brief history of seismology given by a Duncan car Agony, 0:11:45.880 --> 0:11:48.560 which was my source on most of this historical stuff, 0:11:49.640 --> 0:11:51.760 one of the main events that seemed to trigger the 0:11:51.800 --> 0:11:55.240 modern era of earthquake research was the Lisbon earthquake of 0:11:55.280 --> 0:11:59.440 seventeen fifty five, which was huge and had crazy effects 0:11:59.480 --> 0:12:03.800 throughout are up, including causing uh Sasia's or Seisha's. I 0:12:03.800 --> 0:12:07.920 believe it's satias, which are standing waves in these enclosed 0:12:07.920 --> 0:12:10.400 bodies of water. So if you've ever seen standing waves 0:12:10.400 --> 0:12:13.360 in water, it's where instead of the waves propagating along 0:12:13.400 --> 0:12:16.959 the surface, they sort of bob back and forth. Looks 0:12:17.040 --> 0:12:20.080 really crazy, especially if you were going to see that 0:12:20.160 --> 0:12:24.080 in like the lake Oh yeah, yeah, or I don't know, 0:12:24.200 --> 0:12:27.280 I'm picturing the scene in Jurassic Park where where the 0:12:27.280 --> 0:12:30.920 the cup of water is just going but but but 0:12:30.920 --> 0:12:35.600 but not like that, just continually bounce back and forth. Yeah, 0:12:35.880 --> 0:12:39.200 I do not want creepy so this so anyway, this 0:12:39.240 --> 0:12:41.040 event caused some writers at the time to sort of 0:12:41.040 --> 0:12:44.680 see the effects of an earthquake as pressure waves propagating 0:12:44.679 --> 0:12:47.800 outward from a source through the elasticity of the rock 0:12:47.880 --> 0:12:51.400 in the Earth's crust, kind of like sound emanates through 0:12:51.400 --> 0:12:55.120 a solid medium. And from this time through the people 0:12:55.320 --> 0:12:58.720 began to study earthquakes more scientifically. But you can kind 0:12:58.720 --> 0:13:02.160 of understand the faculty they would have, because think about it, 0:13:02.480 --> 0:13:07.719 how do you study earthquakes. You can't like cause an earthquake, 0:13:07.840 --> 0:13:10.520 especially not with the technology of the time, and you 0:13:10.559 --> 0:13:13.280 can't predict when they're going to happen to set up 0:13:13.280 --> 0:13:17.360 your equipment, So it was very much an exercise in 0:13:17.480 --> 0:13:21.400 sort of gathering what data you could after the event 0:13:21.600 --> 0:13:25.719 and then trying to sort of do backwards experiments by 0:13:25.800 --> 0:13:28.440 analyzing the data you had available to you, which is 0:13:28.600 --> 0:13:31.840 very difficult to do, oh sure, especially right given the 0:13:31.840 --> 0:13:34.400 technology of the time and the lack of electricity, let 0:13:34.400 --> 0:13:37.040 alone computers and all of that stuff. Although the first 0:13:37.080 --> 0:13:40.120 step I would say was around the mid eighteen hundreds 0:13:40.360 --> 0:13:45.000 when one Robert Mallett actually coined the term seismology. Yeah, 0:13:45.000 --> 0:13:48.280 and he also sort of brought a quantitative approach to 0:13:48.320 --> 0:13:51.040 studying wave propagation through the earth. He was big into 0:13:51.080 --> 0:13:54.320 looking at maps and collecting all kinds of data and 0:13:54.400 --> 0:13:58.640 analyzing it quantitatively. But then, of course, one of the 0:13:58.679 --> 0:14:02.600 big things that's led to modern era of studying wave 0:14:02.679 --> 0:14:06.560 propagation through the Earth has been the development of seismometers 0:14:06.720 --> 0:14:11.640 or seismometers as one might say for some reason. Uh yeah, 0:14:11.880 --> 0:14:17.080 those being machines that detect seismic waves as seism graphs, 0:14:17.200 --> 0:14:20.040 which I think is the more frequently used term in 0:14:20.040 --> 0:14:24.040 in in popular culture at any rate, are our seismometers 0:14:24.080 --> 0:14:27.480 that record those waves, and many seismometers are in fact 0:14:27.480 --> 0:14:30.840 seismic graphs. Yeah, it would obviously not be very helpful 0:14:30.880 --> 0:14:37.160 to detect waves and then forget about them. Uh no um. 0:14:37.280 --> 0:14:41.000 And and actually there's historical records of these from from 0:14:41.440 --> 0:14:44.040 way before the eighteen hundreds. Yeah. I think we don't 0:14:44.240 --> 0:14:48.560 fully understand exactly everything about this ancient one. But the 0:14:48.600 --> 0:14:52.640 idea is that the first mechanical seismometer was created in 0:14:52.840 --> 0:14:56.640 ancient China by the Han Chinese inventor in general all 0:14:56.680 --> 0:15:01.680 purpose genius Chang Hang in the one thirty two CE. 0:15:01.840 --> 0:15:05.280 Oh goodness. And supposedly this device could tell the operator 0:15:05.360 --> 0:15:10.200 from which direction the vibrations of an earthquake originated, and 0:15:10.280 --> 0:15:15.120 even on at least one occasion anecdotally it recorded an 0:15:15.160 --> 0:15:17.800 earthquake that humans could not feel, so it was like 0:15:17.840 --> 0:15:21.120 too faint for humans to know been one. But the 0:15:21.160 --> 0:15:25.280 machine said, hey, there's an earthquake over here. Cool uh 0:15:25.640 --> 0:15:29.360 during that wave of interest wave huh um. In the 0:15:29.440 --> 0:15:34.200 in the eighteen hundreds, um, several mechanical models were produced 0:15:34.240 --> 0:15:38.080 and kind of refined. Um. By nineteen o three we 0:15:38.160 --> 0:15:43.360 saw the first electromagnetic seismometer, and then digital equipment and 0:15:43.360 --> 0:15:46.800 and data processing technology started to be developed around the 0:15:46.880 --> 0:15:50.480 nineteen seventies or so, we could probably do an entire 0:15:50.640 --> 0:15:54.920 like series of episodes about seismometer technology. And maybe that's 0:15:54.920 --> 0:15:56.960 the thing. I'll poke Jonathan and see if he wants 0:15:57.000 --> 0:15:59.240 to do some episodes about about that on tech stuff, 0:16:00.080 --> 0:16:02.960 because there's so much out there and it's it's kind 0:16:03.040 --> 0:16:05.200 of fascinating. Maybe it would be better in video because 0:16:05.240 --> 0:16:07.760 it's a whole lot of like pictures of pendulums working 0:16:07.760 --> 0:16:10.280 in different ways and spring loaded things. Dude, all of 0:16:10.280 --> 0:16:12.880 a sudden, to Jonathan talk about some pendulums do a 0:16:12.880 --> 0:16:15.720 good job, I bet he would. Okay, No, wait, how 0:16:15.720 --> 0:16:20.480 about some related technology? What about technology to measure those 0:16:20.520 --> 0:16:24.320 secondary effects of earthquakes that we're talking about earlier. Yeah, 0:16:24.360 --> 0:16:27.640 there's some I think within the past few decades. UM 0:16:27.680 --> 0:16:32.520 a device called a sonometer. I think I'm saying that correctly. 0:16:33.400 --> 0:16:41.280 Tenometer either way, Uh yes, tsonometer is probably probably the 0:16:41.280 --> 0:16:44.440 correct way of saying that. UM. A sosonometer is a 0:16:44.560 --> 0:16:48.280 thing that detects changes in water pressure way deep within 0:16:48.320 --> 0:16:51.800 the ocean and can transmit that info via satellite to 0:16:51.960 --> 0:16:56.800 warning centers. It's it's a weighted anchor containing sensors attached 0:16:56.920 --> 0:16:59.560 via tether to a boy on the surface that has 0:16:59.640 --> 0:17:03.080 you know, data crunching computer and transmission system, and it 0:17:03.160 --> 0:17:06.119 can give you a few hours of warning, um for 0:17:06.400 --> 0:17:12.200 tsunami activity. Yeah, so super valuable of course, because I mean, 0:17:12.240 --> 0:17:15.720 tsunamis can be especially devastating when you've got that wall 0:17:15.760 --> 0:17:17.840 of water. I don't know if you've ever seen video 0:17:17.880 --> 0:17:20.800 of what that looks like. It's absolutely terrifying. Oh yeah, 0:17:20.920 --> 0:17:27.040 it's completely mind blowing. Um. Also mind blowing, I find um. 0:17:27.119 --> 0:17:31.920 It was basically readings from these early seismometers that led 0:17:31.920 --> 0:17:35.840 scientists to build the modern hypotheses of the makeup of 0:17:35.880 --> 0:17:38.719 the Earth, starting around like nineteen o nine and then 0:17:38.800 --> 0:17:42.159 ranging up through the thirties. That is when we figured 0:17:42.200 --> 0:17:45.000 out that the Earth has a solid core and molten 0:17:45.119 --> 0:17:48.800 stuff and a crust. And that is so recent it's 0:17:48.840 --> 0:17:50.359 it's crazy to me, Like I had, for some reason 0:17:50.400 --> 0:17:52.800 assumed that had happened in like the sixt dreds at 0:17:52.800 --> 0:17:59.480 some point, but nope, yeah, crazy, So go seismology. Good job. 0:18:00.040 --> 0:18:03.040 That's just astonishing like that we had like relativity and 0:18:03.160 --> 0:18:08.000 quantum physics before we had a full understanding of the 0:18:08.000 --> 0:18:10.640 the Earth, right Yeah, And you know, to be fair, 0:18:10.720 --> 0:18:13.639 you can't go that deep into the earth. Um, you 0:18:13.720 --> 0:18:19.760 also can't go the speed a light, Lauren. Maybe you can't, Joe, Okay, 0:18:20.520 --> 0:18:23.560 but uh so. So it's really cool, of course that 0:18:23.600 --> 0:18:26.119 we were learning all of this stuff and and learning 0:18:26.119 --> 0:18:31.159 how to take measurements of earthquakes. But how has all 0:18:31.200 --> 0:18:34.719 of this learning been applied in actually saving lives and 0:18:34.760 --> 0:18:38.400 preventing damage and predicting earthquakes. Well, I think one thing 0:18:38.480 --> 0:18:40.960 we should actually look at first before we talk about 0:18:41.000 --> 0:18:45.520 predicting earthquakes, because that's, as you will learn, quite a 0:18:45.600 --> 0:18:48.600 strange and iffi proposition. But we can at least talk 0:18:48.640 --> 0:18:51.119 about what we can do to our buildings and our 0:18:51.160 --> 0:18:56.199 cities to make them safer in the event of an earthquake. Yeah. Yeah, Um, 0:18:56.240 --> 0:19:01.119 there are a bunch of different concepts of material and 0:19:01.160 --> 0:19:06.600 construction engineering that can help us safeguard our stuff against 0:19:06.680 --> 0:19:09.760 getting super destroyed. Yeah. I remember. I actually saw a 0:19:09.840 --> 0:19:12.240 headline a while back that was it was a piece 0:19:12.280 --> 0:19:14.840 I think in the wake of a recent earthquake that 0:19:14.920 --> 0:19:18.520 said something along the lines of earthquakes don't kill people, 0:19:19.000 --> 0:19:22.720 buildings do. Right. That seems quite true to me. I 0:19:22.720 --> 0:19:25.040 mean that if you're standing in the middle of a 0:19:25.119 --> 0:19:28.119 field and an earthquake, you're gonna get knocked on your butt. 0:19:28.240 --> 0:19:29.920 But you know, I mean, I mean maybe if a 0:19:30.000 --> 0:19:32.600 fault in the earth opens up directly under your feet, 0:19:33.119 --> 0:19:37.160 that would suck. But but basically it just trips you. Sure, 0:19:37.280 --> 0:19:39.679 but when you come into real danger is when you 0:19:39.720 --> 0:19:43.800 are near a structurally unsound building that come toppling over 0:19:43.840 --> 0:19:47.320 and crush you. Yeah, that that is that is much 0:19:47.359 --> 0:19:50.280 worse than falling on your butt on on a galactic scale. 0:19:51.080 --> 0:19:53.880 So what are some of the answers that material science 0:19:53.920 --> 0:19:58.360 and construction engineering have given us. One of the classic 0:19:58.440 --> 0:20:02.919 ones is called base i selation, And this is super 0:20:02.960 --> 0:20:06.760 not a new idea. Um. There's evidence that Iranian architects, 0:20:06.880 --> 0:20:10.920 or pre Iranian architects rather and engineers were purposefully constructing 0:20:10.960 --> 0:20:15.640 buildings with seismic base isolation starting around like five fifty BC, 0:20:16.600 --> 0:20:20.360 So two five years ago folks were working on this. Well, 0:20:20.400 --> 0:20:22.080 I don't know if I should be impressed, because I 0:20:22.119 --> 0:20:27.040 don't know what it is, Okay. Base isolation is constructing 0:20:27.040 --> 0:20:30.560 two separate layers of a foundation for your building, that 0:20:30.640 --> 0:20:33.600 the layer against the ground is solid with the ground, 0:20:34.040 --> 0:20:38.399 and the the secondary layer between the first one and 0:20:38.440 --> 0:20:41.119 your building is solid with the building, but it is 0:20:41.160 --> 0:20:46.200 capable of sliding against the lower foundation. Okay, Um, so 0:20:46.320 --> 0:20:49.800 if the ground shakes, the upper foundation and the building 0:20:50.000 --> 0:20:55.560 remain intact. Yeah yeah, um or I mean like up 0:20:55.600 --> 0:20:57.240 to a certain point. I think that over like a 0:20:57.840 --> 0:20:59.720 eight on the Richter scale, and you're just kind of 0:21:00.000 --> 0:21:03.359 it anyway. But um, but but this is really cool. 0:21:03.840 --> 0:21:06.960 Archaeologists have found structures such as the Tomb of Cyrus 0:21:07.000 --> 0:21:10.360 that have been standing for over two thousand years, partially 0:21:10.600 --> 0:21:14.000 thanks to this type of structural safeguard. Safeguard, Well, how 0:21:14.000 --> 0:21:15.800 did they do it back then? I mean if they 0:21:15.800 --> 0:21:18.640 didn't have like ball bearings and or whatever, I don't 0:21:18.680 --> 0:21:22.080 know what people would actually use today. Giant loose slabs 0:21:22.080 --> 0:21:24.880 of rock is how they did it, basically, Um, like 0:21:24.880 --> 0:21:26.919 like one giant slab of rock for the base and 0:21:26.960 --> 0:21:30.520 a and a secondary unattached slab of rock for the 0:21:30.640 --> 0:21:34.720 secondary base. I can just imagine the ancient Persian conversation 0:21:34.840 --> 0:21:37.639 that like create you know, like you can't have just 0:21:37.760 --> 0:21:41.280 one slab Nope, nope, we need two slabs here because 0:21:41.280 --> 0:21:43.840 then your earthquake comes and what are you going to do? 0:21:43.920 --> 0:21:50.240 You have an exposed Cyrus corpse that would just be rude. 0:21:50.480 --> 0:21:54.320 We don't we can't have that, um modern okay, oh sorry, 0:21:54.359 --> 0:21:56.679 I just want to update. I am impressed. Now that's smart. 0:21:58.160 --> 0:21:59.679 Yeah yeah, well, I mean it shows that they were 0:21:59.680 --> 0:22:02.159 thinking about it, and even thinking about it at that 0:22:02.200 --> 0:22:06.080 point in time was probably pretty impressive. Modern Ly, a 0:22:06.080 --> 0:22:08.760 lot of buildings that are in danger zones will use 0:22:08.880 --> 0:22:14.159 these things called lead rubber bearing pads between the solid 0:22:14.200 --> 0:22:17.560 foundation and the building. And and these pads consist of 0:22:17.600 --> 0:22:21.520 a solid lead core that's wrapped in in alternating layers 0:22:21.640 --> 0:22:28.560 of rubber and steel bands. So vertically speaking, it's super solid. UM. 0:22:28.600 --> 0:22:31.760 Horizontally it's wibbly wabbli right, so it's not going to 0:22:31.880 --> 0:22:35.840 get crushed, but it can shimmy. Yeah there yeah. UM. 0:22:36.119 --> 0:22:39.639 And a newish technology out of a Japanese company called 0:22:39.720 --> 0:22:45.840 Air Dunsion Systems Incorporated UM can temporarily suspend a smallish 0:22:45.880 --> 0:22:48.680 structure like a private home, on a cushion of air 0:22:49.200 --> 0:22:53.280 as a secondary foundation. UM. They work by having these 0:22:53.320 --> 0:22:57.480 seismic sensors in the homes primary foundation detect a coming 0:22:57.560 --> 0:23:01.320 quake and UM when that happened, and a really powerful 0:23:01.600 --> 0:23:03.919 air compressor will activate and feel like a like an 0:23:03.920 --> 0:23:09.040 air bag in the secondary foundation in less than a second. Um. 0:23:09.080 --> 0:23:11.600 And then you know, when when the sensors detect the 0:23:11.600 --> 0:23:14.200 earthquake is over, the compressor switches off and the bag deflates, 0:23:14.280 --> 0:23:18.280 kind of bringing the home back down, um gently onto 0:23:18.320 --> 0:23:21.879 its first foundation. It's only lifting the structure like a 0:23:21.880 --> 0:23:24.960 little over an inch in the air. Maybe so, but 0:23:25.080 --> 0:23:26.359 that can make a difference. But that can make a 0:23:26.400 --> 0:23:29.760 huge difference. Yeah, yeah, so uh kind of inexpensive way 0:23:29.800 --> 0:23:34.479 I suppose of conducting a base isolation on, especially a 0:23:34.520 --> 0:23:37.600 small home. As I read that the company was hoping 0:23:37.640 --> 0:23:40.359 to expand their systems for use in high rises, but 0:23:40.640 --> 0:23:43.320 I haven't been able to find anything more recent about 0:23:43.320 --> 0:23:45.720 what they've been doing, so I don't know. I hope 0:23:45.720 --> 0:23:48.280 they're out there. Yeah, good luck to them. Yeah. Well, 0:23:48.320 --> 0:23:50.640 one of the things that I think is interesting is 0:23:50.920 --> 0:23:56.600 studying the way that the ground actually transfers energy to buildings. 0:23:56.960 --> 0:24:00.400 Oh yeah, because that's really your problem, right, that you've 0:24:00.400 --> 0:24:03.159 got all this energy coming into a rigid structure, and 0:24:03.200 --> 0:24:06.399 how do you dissipate it? Right? But I mean, really, 0:24:06.440 --> 0:24:11.679 the damage that earthquakes cause is because of how efficient 0:24:12.000 --> 0:24:17.359 energy transfer is. Like thanks a lot physics, um, but 0:24:17.359 --> 0:24:21.600 but see any given object has a resonant frequency or 0:24:21.640 --> 0:24:23.760 a group of resonant frequencies. And we've talked about that 0:24:23.760 --> 0:24:26.040 a little bit on the show before. Um it means 0:24:26.080 --> 0:24:29.520 that when when the object vibrates, based on its its 0:24:29.560 --> 0:24:31.960 size and its shape and the materials it's made of, 0:24:32.359 --> 0:24:36.280 it's going to resonate at this specific frequency or group 0:24:36.280 --> 0:24:39.440 of frequencies maybe, And it's really hard to get something 0:24:39.480 --> 0:24:44.160