1 00:00:04,200 --> 00:00:08,500 This is geology, B. I'm all of us, trampled, unless 2 00:00:08,500 --> 00:00:12,000 you live in a place like Japan or California, most of us have 3 00:00:12,000 --> 00:00:15,400 never experienced an earthquake, but we certainly hear about them 4 00:00:15,400 --> 00:00:18,900 regularly, especially when the damage they reek is newsworthy 5 00:00:19,500 --> 00:00:22,500 this podcast. Focuses on earthquakes, the 6 00:00:22,500 --> 00:00:26,100 geological faults on which they occur, and their impact on 7 00:00:26,100 --> 00:00:29,800 humans. James Jackson is Professor of 8 00:00:29,800 --> 00:00:33,900 active tectonics at Cambridge University and an expert on the 9 00:00:33,900 --> 00:00:37,600 geological processes including earthquakes that are shaping our 10 00:00:37,600 --> 00:00:41,100 continents today. James Jackson, welcome to 11 00:00:41,100 --> 00:00:44,600 geology B, what's going on geological speaking. 12 00:00:44,600 --> 00:00:49,400 When an earthquake strikes, this week happens when rocks break 13 00:00:49,800 --> 00:00:52,700 and slide past each other on surfaces called, folks. 14 00:00:52,700 --> 00:00:56,200 They could think of a knife cut in the earth and the rocks are 15 00:00:56,200 --> 00:00:58,300 sliding past each other on. At knife, cut. 16 00:00:58,600 --> 00:01:02,000 Now normally it's held together by friction and you have to 17 00:01:02,000 --> 00:01:05,300 overcome that friction. So imagine you have a brick on a 18 00:01:05,300 --> 00:01:08,200 table and you push the brick. You have to push a certain 19 00:01:08,200 --> 00:01:11,100 amount before it actually jumps forward and that's what's 20 00:01:11,100 --> 00:01:13,000 happening in. The earthquake is friction which 21 00:01:13,000 --> 00:01:17,600 is an overcome and it's the shaking as the Rocks grind past 22 00:01:17,600 --> 00:01:20,600 each other, doing that movement, which causes the damage, the 23 00:01:20,600 --> 00:01:23,000 earthquake people feel and is the shaking. 24 00:01:23,500 --> 00:01:28,800 But the cause of it, is this breaking of rocks on false So do 25 00:01:28,800 --> 00:01:32,400 we know where all these Faults Are what we look like cotton 26 00:01:32,400 --> 00:01:35,100 under that, because what happens is that, they move again and 27 00:01:35,100 --> 00:01:38,400 again, in earthquakes, the same fault, will move again and again 28 00:01:38,400 --> 00:01:41,500 it only moves a few meters even in the biggest earthquakes, but 29 00:01:41,500 --> 00:01:45,700 given the huge time we have on Earth, after thousands of these 30 00:01:45,700 --> 00:01:47,800 earthquakes, you actually make the landscape. 31 00:01:48,100 --> 00:01:53,000 So the landscape is often a clue to where The Faults Are and so 32 00:01:53,000 --> 00:01:55,700 reading the landscape is a bit like learning to read at new 33 00:01:55,700 --> 00:01:59,100 alphabet when you book once you speak, The language, you have a 34 00:01:59,107 --> 00:02:01,000 head start and where these things are. 35 00:02:01,700 --> 00:02:05,400 Does that mean that if there are faults away from landscape 36 00:02:05,500 --> 00:02:07,600 features? We don't know where they are. 37 00:02:08,300 --> 00:02:11,100 Well, most of the folks have some effect in the landscape. 38 00:02:11,100 --> 00:02:15,200 So the folks can either move up and down or sideways moving up 39 00:02:15,200 --> 00:02:17,800 and down, makes mountains, or it makes basins and lakes, 40 00:02:17,800 --> 00:02:19,500 depending, which side of the fault you are. 41 00:02:19,900 --> 00:02:23,200 And so that's a help and places where this is going on the other 42 00:02:23,200 --> 00:02:25,600 folks move sideways. As they do an example, the San 43 00:02:25,600 --> 00:02:29,300 Andreas Fault in California, They still end up as features in 44 00:02:29,300 --> 00:02:32,900 the landscape because as the Rocks grind past each other and 45 00:02:32,900 --> 00:02:36,600 folks who get broken up and they get the easily eroded by streams 46 00:02:36,600 --> 00:02:39,400 and rivers and so on. So, they quite often make linear 47 00:02:39,800 --> 00:02:42,900 values, or Scott's or features in the landscape, which are 48 00:02:42,908 --> 00:02:46,500 quite often visible from the air, for example, in are 49 00:02:46,500 --> 00:02:49,200 photographs or Satellite photographs and they're often 50 00:02:49,200 --> 00:02:51,200 followed by roads and rail hissing. 51 00:02:51,200 --> 00:02:55,300 So, people exploit these things also So when an earthquake 52 00:02:55,300 --> 00:02:59,100 strikes, how much movement might occur across a fault? 53 00:03:00,100 --> 00:03:03,000 Well, that is basically what determines the size of the 54 00:03:03,000 --> 00:03:05,700 earthquake, or the magnitude or the Richter magnitude has been 55 00:03:05,700 --> 00:03:08,300 straight As refer to it. But even in the really ready, 56 00:03:08,300 --> 00:03:11,700 biggest earthquakes, the movement is 1020 meters of 57 00:03:11,700 --> 00:03:14,100 biggest. We know, of, in modern times was 58 00:03:14,100 --> 00:03:18,000 the one in Japan in 2011, which moved 50 meters which was 59 00:03:18,000 --> 00:03:20,400 extraordinary, but that really was unusual. 60 00:03:20,800 --> 00:03:23,500 Most the small earthquakes will move just a few millimeters or 61 00:03:23,500 --> 00:03:24,200 so. Two meters. 62 00:03:24,400 --> 00:03:26,700 So that's really what determines the size of the earthquake. 63 00:03:27,100 --> 00:03:30,000 So thank you Nate earthquake. You're talking about maybe 10 64 00:03:30,000 --> 00:03:33,500 meters or more slip a magnitude 5 earthquake. 65 00:03:33,500 --> 00:03:36,400 You're talking about a centimeter or a few centimeters. 66 00:03:36,700 --> 00:03:38,900 That's really what determines the size of the earthquake. 67 00:03:39,500 --> 00:03:41,300 And how could we measure this slip? 68 00:03:42,200 --> 00:03:43,400 Well, there are various ways of doing it. 69 00:03:43,400 --> 00:03:47,100 Sometimes it breaks the surface, and you can just see it because 70 00:03:47,100 --> 00:03:49,900 actually, the magnitude also determines how long the 71 00:03:49,900 --> 00:03:51,400 faulting. So the great earthquake in 72 00:03:51,400 --> 00:03:55,500 smarter in 2004 which produce sucks Me for example, was 1,200 73 00:03:55,500 --> 00:03:58,100 kilometers long. That's from here, where I'm 74 00:03:58,100 --> 00:04:01,300 speaking Cambridge London to Rome, right? 75 00:04:01,400 --> 00:04:04,100 That's a great length and it, moved 20 meters or so huge 76 00:04:04,100 --> 00:04:06,100 amount. So, that kind of thing is easy 77 00:04:06,100 --> 00:04:08,200 to spot. The smaller ones are often 78 00:04:08,200 --> 00:04:10,300 underground. A don't have any motion visible 79 00:04:10,300 --> 00:04:14,500 at the surface at all, but we have very sophisticated ways of 80 00:04:14,800 --> 00:04:17,600 seeing what's going on. We can tell from the sound or 81 00:04:17,600 --> 00:04:20,800 shaking that the earthquakes, generate how much that there's 82 00:04:20,800 --> 00:04:21,800 been. That's the science of 83 00:04:21,800 --> 00:04:24,700 seismology. We can see How much the ground 84 00:04:24,700 --> 00:04:29,500 surface roundabout moves by looking from space with radar 85 00:04:29,500 --> 00:04:33,600 images, or Optical images? And we also now use GPS to do 86 00:04:33,600 --> 00:04:38,300 the same thing, GPS is the technology that is used for your 87 00:04:38,300 --> 00:04:42,600 sat-nav, a, from the car, for example, which if you process it 88 00:04:42,600 --> 00:04:45,300 carefully enough, will show you how things move to within a few 89 00:04:45,300 --> 00:04:47,500 millimeters. You don't need that accuracy for 90 00:04:47,500 --> 00:04:50,900 your car, but we can do it when we use it for our purposes. 91 00:04:51,300 --> 00:04:54,200 So did we do that? For example, for the big T 11 92 00:04:54,200 --> 00:04:56,300 earthquake in Japan? Yes, you do. 93 00:04:56,500 --> 00:04:59,300 Because actually and this is quite interesting, the analogy I 94 00:04:59,300 --> 00:05:03,400 gave you a pushing a brick across the surface of the table 95 00:05:03,400 --> 00:05:06,500 isn't quite right. Imagine you had a sponge and you 96 00:05:06,500 --> 00:05:08,100 push the sponge across the surface. 97 00:05:08,300 --> 00:05:11,200 The sponge will actually compress quite a bit before it 98 00:05:11,200 --> 00:05:13,400 suddenly jerked forward. And that's what happens to the 99 00:05:13,400 --> 00:05:15,300 Rocks. So you can see the Rocks 100 00:05:15,300 --> 00:05:19,400 actually bending and bulging before earthquakes and you can 101 00:05:19,400 --> 00:05:22,500 see after earthquakes how they relax again and they change 102 00:05:22,500 --> 00:05:24,500 shape. So after The great Japan 103 00:05:24,500 --> 00:05:28,200 earthquake in 2011, the whole of Japan on that and stretched, it 104 00:05:28,200 --> 00:05:31,700 relaxed about 3 meters. So Japan was 3 meters wider 105 00:05:31,700 --> 00:05:35,800 after the earthquake and it was before and do we measure that by 106 00:05:35,800 --> 00:05:37,900 having GPS sensors on each Coast? 107 00:05:38,400 --> 00:05:40,300 Well changing. So, in fact, there are hundreds 108 00:05:40,300 --> 00:05:44,500 or thousands of GPS sites measuring all the time because 109 00:05:44,500 --> 00:05:48,300 ditions in places like Japan and that's increasingly throughout 110 00:05:48,300 --> 00:05:51,100 the world. And part of the reason is to 111 00:05:51,100 --> 00:05:53,600 monitor earthquakes. And so on these sites will tell 112 00:05:53,700 --> 00:05:56,200 Where they are relative to each other through within a few 113 00:05:56,200 --> 00:05:58,700 millimeters. So they move several meters, 114 00:05:58,700 --> 00:06:01,600 that's very, very easy to spot. But actually, to be honest, the 115 00:06:01,600 --> 00:06:03,900 main reason they're being installed everywhere around the 116 00:06:03,900 --> 00:06:07,400 world is this is now how you define property boundaries on 117 00:06:07,400 --> 00:06:10,300 maps, you no longer say the boundary of my house is where 118 00:06:10,300 --> 00:06:13,400 that tree is or where this river is, you just give it a latitude 119 00:06:13,400 --> 00:06:16,900 and longitude from the GPS and that's the basis now of modern 120 00:06:16,900 --> 00:06:19,200 surveying. So that's why that is now 121 00:06:19,200 --> 00:06:22,800 rapidly expanding as a resource. The other thing you can do, this 122 00:06:22,800 --> 00:06:25,300 is another Modern trick, which is very interesting. 123 00:06:25,300 --> 00:06:29,200 You can do this with radar images, from space or Optical 124 00:06:29,200 --> 00:06:32,800 images from space. Is you take a photograph of a 125 00:06:32,808 --> 00:06:35,500 large area and you divide it up into little pixels, little 126 00:06:35,500 --> 00:06:39,500 patches on the ground, maybe 50 centimeters across and then you 127 00:06:39,500 --> 00:06:41,300 take another picture after the earthquake. 128 00:06:41,600 --> 00:06:43,400 And in the region where the fault is. 129 00:06:43,700 --> 00:06:46,400 These pixels have moved around on the edges of your picture. 130 00:06:46,400 --> 00:06:49,200 If they haven't moved around. So, you simply superimpose one 131 00:06:49,200 --> 00:06:51,600 on the other and round, the edges of your picture. 132 00:06:51,600 --> 00:06:53,500 The pixels have moved, they all overlap. 133 00:06:53,700 --> 00:06:55,900 Perfectly. And we're the folks is they've 134 00:06:55,900 --> 00:06:58,500 all moved slightly and you can measure how much they've moved 135 00:06:58,500 --> 00:07:01,600 in this will again give you the movement of the ground within a 136 00:07:01,608 --> 00:07:04,400 few centimeters. It's not as accurate as GPS, but 137 00:07:04,400 --> 00:07:07,800 you cover a much wider area, instead of just a single point 138 00:07:08,200 --> 00:07:10,600 and these things are very powerful when they're all used 139 00:07:10,600 --> 00:07:12,900 together. So if you use seismology and the 140 00:07:12,900 --> 00:07:17,300 space Imaging and the GPS all at the same time, you really can 141 00:07:17,300 --> 00:07:19,900 nail what happens in extraordinary detail which we 142 00:07:19,900 --> 00:07:21,900 could only have dreamt about 20 years ago. 143 00:07:22,600 --> 00:07:24,800 That's amazing. So So, with these satellite 144 00:07:24,800 --> 00:07:27,800 image Maps, can we but of actually see this building 145 00:07:27,800 --> 00:07:30,000 moved. So many meters over that way and 146 00:07:30,200 --> 00:07:33,000 river move that way. Yes, indeed. 147 00:07:33,000 --> 00:07:35,300 You can easily and actually, this is a bit of a pain in the 148 00:07:35,300 --> 00:07:37,700 neck for land, surveys in countries like New Zealand. 149 00:07:37,700 --> 00:07:40,800 Their National Grid is moving around all the time, it has to, 150 00:07:41,400 --> 00:07:44,400 it has to change with time because because this is 151 00:07:44,400 --> 00:07:46,800 happening throughout the country and the same is true in Japan. 152 00:07:47,100 --> 00:07:50,500 The downside of measuring things to Within A millimeter is that 153 00:07:50,500 --> 00:07:52,800 they are moving within a few millimeters a year. 154 00:07:52,800 --> 00:07:54,300 Most of these, are they Any of you. 155 00:07:55,100 --> 00:07:58,100 So although most of the earthquakes we hear about happen 156 00:07:58,100 --> 00:08:01,400 in areas that we know high risk, like, you mentioned Sumatra in 157 00:08:01,400 --> 00:08:04,800 Japan and I suppose that apply to the whole Western rim of the 158 00:08:04,800 --> 00:08:08,300 Pacific, as well as places, like, California earthquakes 159 00:08:08,300 --> 00:08:11,600 actually, do also happen elsewhere, but much less often. 160 00:08:11,600 --> 00:08:14,500 Why is that? Yes, this is an interesting 161 00:08:14,500 --> 00:08:18,700 feature of our modern Earth today is that the really, really 162 00:08:18,700 --> 00:08:22,200 big earthquakes happen around the rim of the oceans and the 163 00:08:22,207 --> 00:08:26,500 Pacific and in place. Is like Indonesia, but that is 164 00:08:26,500 --> 00:08:28,100 not actually where most people die. 165 00:08:28,100 --> 00:08:31,400 In earthquakes, many more people die in earthquakes in the middle 166 00:08:31,400 --> 00:08:33,200 of continents and particularly in Asia. 167 00:08:33,200 --> 00:08:35,500 So the Great Earthquake felt for Trans all the way through the 168 00:08:35,500 --> 00:08:39,400 Mediterranean, the Middle East and into Asia, all the way to 169 00:08:39,400 --> 00:08:43,500 China through places like North India, Tibet and Central Asia 170 00:08:43,799 --> 00:08:47,400 that area which is a huge, huge area as small earthquakes, but 171 00:08:47,400 --> 00:08:50,500 they kill many more people. And there are multiple reasons 172 00:08:50,500 --> 00:08:54,300 for that but the reason why it's so different is Because the 173 00:08:54,300 --> 00:08:58,900 continents behave in a different way, from the oceans, the oceans 174 00:08:59,200 --> 00:09:03,100 are really the story of plate tectonics which everybody learns 175 00:09:03,100 --> 00:09:06,500 about now even in primary school that the Earth is split up into 176 00:09:06,500 --> 00:09:09,700 these spherical caps which move around relative to each other 177 00:09:10,200 --> 00:09:12,700 and the earthquakes happen, where these caps interact with 178 00:09:12,700 --> 00:09:16,100 each other and round, the edges of the oceans places like Japan, 179 00:09:16,100 --> 00:09:18,800 South America, Central America, or Alaska. 180 00:09:18,800 --> 00:09:21,600 For example. What happens is the ocean slides 181 00:09:21,600 --> 00:09:23,500 underneath the adjacent continent? 182 00:09:23,600 --> 00:09:26,300 Rather like a conveyor belt. Imagine the conveyor belt or 183 00:09:26,300 --> 00:09:29,600 escalator on the staircase, going back into the ground. 184 00:09:29,600 --> 00:09:31,800 That's what's happening to the ocean as it slides on the 185 00:09:31,800 --> 00:09:35,000 continent and that interface where we ocean slides under the 186 00:09:35,000 --> 00:09:37,300 continent, that's where the earthquakes happen. 187 00:09:37,300 --> 00:09:40,700 So there's essentially one fault, which is doing the job 188 00:09:40,800 --> 00:09:43,700 and it has to move pretty often because it's moving quite fast. 189 00:09:43,700 --> 00:09:45,500 Typically a few centimeters per year. 190 00:09:46,100 --> 00:09:49,000 Now, the continents are all the different because the continents 191 00:09:49,000 --> 00:09:51,600 are not really part of that story. 192 00:09:51,600 --> 00:09:55,100 The continents are like, Floating on these plates. 193 00:09:55,100 --> 00:09:57,900 They like passengers. And they don't cause any 194 00:09:57,900 --> 00:09:59,500 trouble. If they're just an island in the 195 00:09:59,500 --> 00:10:02,100 middle of the Pacific or something, you get a problem 196 00:10:02,100 --> 00:10:04,800 where one continent bashes into another continent. 197 00:10:04,900 --> 00:10:07,300 And this is the problem with India, for example, which 198 00:10:07,300 --> 00:10:12,000 belongs adjacent to Madagascar and Antarctica and Australia in 199 00:10:12,000 --> 00:10:15,500 the Southern Ocean, it broke away and crossed as an island in 200 00:10:15,500 --> 00:10:19,100 the Indian Ocean until it bashed into Asia. 201 00:10:19,600 --> 00:10:22,000 And when you have a situation because the continents are made 202 00:10:22,000 --> 00:10:25,600 of different material from the ocean, it's much less dense the 203 00:10:25,600 --> 00:10:28,700 confidence that I life jacket. So they simply won't go down 204 00:10:28,700 --> 00:10:29,900 there. I go down the hole like the 205 00:10:29,900 --> 00:10:32,900 escalator or the conveyor belt and they just bash into the next 206 00:10:32,900 --> 00:10:34,900 continent and the whole thing crunches up. 207 00:10:35,300 --> 00:10:38,100 And so what's happened in the case of India is India, has 208 00:10:38,100 --> 00:10:41,800 smashed up Asia all the way from the edge of the Himalayas to 209 00:10:41,800 --> 00:10:44,000 Mongolia which is 3,000 kilometers further. 210 00:10:44,000 --> 00:10:46,100 North, the whole place is smashed up. 211 00:10:46,400 --> 00:10:48,500 So there are many, many earthquakes are of a much wider 212 00:10:48,500 --> 00:10:53,100 region instead of essentially being a single big fault on big 213 00:10:53,100 --> 00:10:55,400 earthquake, Do you have around the edges of the oceans? 214 00:10:56,800 --> 00:11:00,800 So what happens over millions and millions of years? 215 00:11:01,100 --> 00:11:06,400 As movement happens repeatedly over either a single fault as 216 00:11:06,400 --> 00:11:09,900 you mentioned at the plate boundaries or this massive 217 00:11:09,900 --> 00:11:12,800 network of faults that you may have in the interior of a 218 00:11:12,800 --> 00:11:15,700 continent. Well, what happened to India, 219 00:11:15,800 --> 00:11:19,200 collided with a sure about 50 million years ago and it's going 220 00:11:19,200 --> 00:11:22,300 at about 4 centimeters per year. It's not like a car crash, it's 221 00:11:22,300 --> 00:11:26,400 not stopped, it's still plowing into Asia that rate for He's 222 00:11:26,400 --> 00:11:28,900 here about the rate, your fingernails grow and over 50 223 00:11:28,900 --> 00:11:33,700 million years, then India has plowed 2000 km into Asian crush 224 00:11:33,700 --> 00:11:35,700 it up. And that's why there are 225 00:11:35,700 --> 00:11:38,700 hundreds and thousands even of faults in that part of Central 226 00:11:38,700 --> 00:11:40,600 Asia. And because each of them is 227 00:11:40,600 --> 00:11:44,500 contributing to that job of allowing India to move north, 228 00:11:44,700 --> 00:11:48,200 eat particular, one doesn't have to move very often whereas The 229 00:11:48,200 --> 00:11:50,500 Faults offshore Japan or South America. 230 00:11:50,500 --> 00:11:54,200 For example, they have to do all the work, they're moving 231 00:11:54,200 --> 00:11:56,200 frequently because they have to do all the work. 232 00:11:56,300 --> 00:11:59,600 Does anybody want V to do it? So words earthquake to repeat 233 00:11:59,600 --> 00:12:04,000 every few tens or maybe a hundred years or so in Japan and 234 00:12:04,000 --> 00:12:07,000 South America, in Central Asia, where there thousands of faults, 235 00:12:07,200 --> 00:12:09,400 each fault, may only repeat its movements. 236 00:12:09,400 --> 00:12:13,500 Every few thousand years often Way Beyond human memory or 237 00:12:13,500 --> 00:12:15,500 recorded history. And so they tend to catch 238 00:12:15,500 --> 00:12:16,500 people. Unawares. 239 00:12:16,700 --> 00:12:19,200 People are unaware that they're living in a dangerous place 240 00:12:19,600 --> 00:12:21,400 because there are earthquakes all over the place. 241 00:12:21,400 --> 00:12:23,600 There's nothing particularly distinguishes where they are. 242 00:12:24,600 --> 00:12:28,300 Let's come down to the Fatal Attraction between cities and 243 00:12:28,300 --> 00:12:31,900 earthquakes. Why do we build cities in areas 244 00:12:31,900 --> 00:12:35,500 that are prone to earthquakes? Yeah, this is an interesting 245 00:12:35,500 --> 00:12:37,500 feature again of Central Asia, really? 246 00:12:37,500 --> 00:12:40,500 Or this great Alpine Himalayan earthquake belt from the 247 00:12:40,500 --> 00:12:44,700 Mediterranean to China is that earthquakes occur and seemed 248 00:12:44,700 --> 00:12:48,700 quite often to Target places where people live and you think 249 00:12:48,700 --> 00:12:52,100 it's just as bad luck or is this the kind of being vindictive? 250 00:12:52,300 --> 00:12:55,900 And the reason for that is that the earthquakes and the faults. 251 00:12:56,300 --> 00:13:00,600 Responsible for making the mountains and the particular 252 00:13:00,600 --> 00:13:03,300 responsible for the edges of the mountains where the mountains 253 00:13:03,300 --> 00:13:06,200 meet deserts or high plateaus like to bed. 254 00:13:06,800 --> 00:13:09,200 And that's where people live. If you like living on the edges 255 00:13:09,200 --> 00:13:12,200 of mountains, because that's where the water supply is, its, 256 00:13:12,200 --> 00:13:15,200 where agriculture is possible. It's usually where the trade 257 00:13:15,200 --> 00:13:17,900 route runs on the edge of the mountains and of course it's 258 00:13:17,900 --> 00:13:21,500 strategically important for access to those trade routes as 259 00:13:21,500 --> 00:13:22,900 well. So what happens is that 260 00:13:22,900 --> 00:13:26,100 settlements grow up along those trade routes on the edges of 261 00:13:26,200 --> 00:13:28,800 Mountains and then they develop, and they become bigger and 262 00:13:28,800 --> 00:13:30,100 bigger. And so, the populations 263 00:13:30,100 --> 00:13:33,400 concentrate in these dangerous places, it would be fine to live 264 00:13:33,400 --> 00:13:36,600 in the middle of the flat desert in Iran or Central Asia, but 265 00:13:36,600 --> 00:13:38,700 there is no likelihood there. There's no Waters and 266 00:13:38,700 --> 00:13:41,000 agriculture possible. You can't live there. 267 00:13:41,100 --> 00:13:44,600 And so you live with where life is possible in these desert 268 00:13:44,600 --> 00:13:48,300 countries and that is almost inevitably places where life is 269 00:13:48,300 --> 00:13:51,900 possible because the faulting has created the circumstances 270 00:13:51,900 --> 00:13:54,100 that make agriculture and water supply possible. 271 00:13:55,400 --> 00:13:59,200 So, You've described how that can happen at the edge of 272 00:13:59,200 --> 00:14:01,900 mountain ranges such as the Himalayas or the Alps where you 273 00:14:01,908 --> 00:14:05,400 have well in the Himalayan case India plowing into Asia. 274 00:14:06,000 --> 00:14:09,000 Does that also apply on coastlines? 275 00:14:09,000 --> 00:14:12,800 Because we love to build cities on coastlines in places where 276 00:14:12,800 --> 00:14:14,900 the earthquakes. Yes, is tectonic plates that 277 00:14:14,900 --> 00:14:17,900 just crunched together. They can also pull apart and 278 00:14:17,900 --> 00:14:22,200 drift apart, and that's for example, why the coastline is 279 00:14:22,200 --> 00:14:25,400 where it is between Greece and Turkey or between Norway and 280 00:14:25,400 --> 00:14:27,500 Scotland. Although Annoying Scotland is no 281 00:14:27,500 --> 00:14:29,500 longer active. It did it all about 100 million 282 00:14:29,500 --> 00:14:33,300 years ago, but now it's active in places like Greece, Central 283 00:14:33,300 --> 00:14:36,300 Central Aegean, Sea of Japan, Greece, and Turkey, and indeed, 284 00:14:36,300 --> 00:14:38,000 that is why the coastline is where it is. 285 00:14:38,000 --> 00:14:40,800 That's where most of the action is, that's where the earthquakes 286 00:14:40,800 --> 00:14:42,800 are. And so, if you live in countries 287 00:14:42,800 --> 00:14:46,300 where there are earthquakes, it's a good idea to ask why is 288 00:14:46,300 --> 00:14:48,000 landscape? Like it does. 289 00:14:48,000 --> 00:14:52,200 And that's nearly always because of faulting associated with 290 00:14:52,200 --> 00:14:55,000 earthquakes in places like California or the Mediterranean 291 00:14:55,000 --> 00:14:58,400 Middle, East Central Asia. Zeeland East Africa, the 292 00:14:58,400 --> 00:15:01,200 mountains are there because of the activity and faults in 293 00:15:01,200 --> 00:15:05,500 earthquake. So what impact have earthquakes 294 00:15:05,500 --> 00:15:08,700 had over history on these cities that have succumbed to this 295 00:15:08,700 --> 00:15:13,900 attraction to earthquakes well. So this is very interesting that 296 00:15:13,900 --> 00:15:17,600 the number of modern cities which have grown into a huge 297 00:15:17,600 --> 00:15:21,700 population, centers along, for example, the old Silk routes, 298 00:15:21,800 --> 00:15:24,700 which connected China, to the Mediterranean, a lot of cities, 299 00:15:24,700 --> 00:15:27,000 along those routes have been destroyed, Multiple times in the 300 00:15:27,000 --> 00:15:30,100 past, but in the past, they were intended to be rather small, 301 00:15:30,500 --> 00:15:34,400 they tended to be stopovers on trade routes but now there are 302 00:15:34,400 --> 00:15:37,700 any of them even capital cities of countries in Central Asia and 303 00:15:37,700 --> 00:15:40,100 they've been destroyed in the past, but whereas, in the past 304 00:15:40,100 --> 00:15:44,300 say, they're unlucky, they lost 10,000 people or so now they 305 00:15:44,300 --> 00:15:48,100 have cities of million or more and they're very much more 306 00:15:48,100 --> 00:15:49,800 vulnerable. It's still in the dangerous 307 00:15:49,800 --> 00:15:53,400 place but they've increased the population dramatically without 308 00:15:53,500 --> 00:15:57,600 I'm sorry to say in most cases. Their resilience to the 309 00:15:57,600 --> 00:15:59,300 earthquakes that are bound to happen again. 310 00:16:00,200 --> 00:16:03,500 Can we help people in these cities, prepare for the next 311 00:16:03,500 --> 00:16:06,700 earthquake, by predicting when it'll happen or roughly when 312 00:16:06,700 --> 00:16:10,200 it'll happen, for example, I know that we can detect bulging 313 00:16:10,200 --> 00:16:14,300 movement on volcanoes that for warn us of eruptions on 314 00:16:14,300 --> 00:16:16,500 volcanoes. Does that also apply on the 315 00:16:16,500 --> 00:16:18,300 tectonic scale? Two continents. 316 00:16:18,900 --> 00:16:23,100 Well, now you've touched a very interesting question and we have 317 00:16:23,100 --> 00:16:25,400 to be careful how we use words in this area. 318 00:16:26,200 --> 00:16:29,000 Short term prediction means saying, there's going to be an 319 00:16:29,000 --> 00:16:32,300 earthquake sometime within. You know, say let's say next 320 00:16:32,300 --> 00:16:36,700 Wednesday, plus or minus of a and in some particular place 321 00:16:37,000 --> 00:16:40,200 such and such a size and we can't do that the science isn't 322 00:16:40,200 --> 00:16:43,800 there, people have looked very hard for precursors. 323 00:16:43,800 --> 00:16:46,400 They're called with some sort of Warning Sign beforehand. 324 00:16:46,900 --> 00:16:50,000 There's nothing which has been found to be reliable and it's 325 00:16:50,000 --> 00:16:53,600 not something which has been successful. 326 00:16:54,200 --> 00:16:57,600 We contrast that with Forecasting, long-term 327 00:16:57,600 --> 00:16:59,800 forecasting is fine. Long-term forecast is simply 328 00:16:59,800 --> 00:17:02,100 saying where there's been an earthquake in the past few days 329 00:17:02,100 --> 00:17:04,200 about it will happen again in the future sometime. 330 00:17:04,200 --> 00:17:07,200 You can't say when but we can say quite a lot with a bit of 331 00:17:07,200 --> 00:17:10,099 work, about how big that earthquake will be, what its 332 00:17:10,099 --> 00:17:13,099 characteristics will be, how much the likely shaking will be 333 00:17:13,300 --> 00:17:16,500 along last, how big it will be, how much the default might move. 334 00:17:16,500 --> 00:17:18,700 But all these things are of interest to Architects and 335 00:17:18,700 --> 00:17:22,800 engineers and planners because if they know what the threat is, 336 00:17:22,800 --> 00:17:25,700 what they're up against, they can actually design things for 337 00:17:25,700 --> 00:17:28,900 it and that's It's been very successful again in countries 338 00:17:28,900 --> 00:17:32,100 around the Pacific Rim. For example, it's much harder to 339 00:17:32,100 --> 00:17:36,000 do in Central Asia because there are more faults most that we 340 00:17:36,000 --> 00:17:39,800 don't know about and there are generally other priorities and 341 00:17:39,800 --> 00:17:43,600 this is the problem is that in many cities in places where 342 00:17:43,600 --> 00:17:47,300 earthquakes are less frequent, but more dangerous in those 343 00:17:47,300 --> 00:17:48,900 places people have other priorities. 344 00:17:48,900 --> 00:17:51,300 So if I was to say to you that the last earthquake was 500 345 00:17:51,300 --> 00:17:53,300 years ago in your city, you would say. 346 00:17:53,300 --> 00:17:56,000 Well everyday, I takes me two hours to get to work. 347 00:17:56,200 --> 00:17:58,100 As congestion, the air quality is rubbish. 348 00:17:58,100 --> 00:18:02,200 Our problems of water supply traffic Thomas on this 349 00:18:02,200 --> 00:18:05,000 earthquake, 500 years ago, that's not my problem, but 350 00:18:05,000 --> 00:18:08,500 actually, it is your problem eventually, but it's not highly 351 00:18:08,500 --> 00:18:11,800 prioritized by contrast. If you lived in, in Chile, for 352 00:18:11,800 --> 00:18:15,000 example, you feel earthquakes all the time, and, you know, 353 00:18:15,000 --> 00:18:17,900 that you'll feel 95. Earthquake every year. 354 00:18:17,900 --> 00:18:20,800 You'll feel 97 probably every ten years and they'll probably 355 00:18:20,800 --> 00:18:22,600 be a magnitude 8 earthquake in your lifetime. 356 00:18:22,800 --> 00:18:25,200 You know, this is not a theoretical threat, it will 357 00:18:25,200 --> 00:18:28,100 affect you, your Children and your grandchildren and people 358 00:18:28,100 --> 00:18:30,200 are quite happy to prioritize it. 359 00:18:30,600 --> 00:18:34,900 And so in fact they're helped around the Pacific Rim by having 360 00:18:34,900 --> 00:18:38,400 many many more earthquakes in the same place repeating as it 361 00:18:38,400 --> 00:18:41,700 were and in Central Asia where they're more distributed and 362 00:18:41,800 --> 00:18:45,100 less frequent in any one particular place and so we can 363 00:18:45,100 --> 00:18:47,900 help them. They need to do the work to put 364 00:18:47,900 --> 00:18:51,300 in the work to know what the hazard is that they're actually 365 00:18:51,300 --> 00:18:54,200 facing. There's no real shortcut to that 366 00:18:54,700 --> 00:18:58,200 but it's just on the whole not. Sighs places like Japan, New 367 00:18:58,200 --> 00:19:02,500 Zealand, California and Chile have put in decades of really 368 00:19:02,600 --> 00:19:06,100 hard, scientific effort to find out what they're up against so 369 00:19:06,100 --> 00:19:09,900 they can plan and prepare and they've been super be successful 370 00:19:09,900 --> 00:19:12,000 at it. When you say what they're up 371 00:19:12,000 --> 00:19:16,100 against, does that mean mapping the faults in detail? 372 00:19:16,100 --> 00:19:20,200 So we have a better idea to east of where the next one might be 373 00:19:20,200 --> 00:19:24,300 that's going to rupture the. Yes certainly that's part of it. 374 00:19:24,500 --> 00:19:26,700 But there are two things which could send a few or an engineer 375 00:19:26,700 --> 00:19:29,300 building a dam. For example, in a River Gorge, 376 00:19:29,300 --> 00:19:32,200 you want to know why that Gorge is there and if the gorge is 377 00:19:32,200 --> 00:19:35,000 there because there's a fault, the rivers flowing down it that 378 00:19:35,000 --> 00:19:37,500 affect how you build your down, which I get physically ripped 379 00:19:37,500 --> 00:19:39,600 apart. So there's an interest in 380 00:19:39,600 --> 00:19:42,700 knowing where the fault itself is for sure, for particular 381 00:19:42,700 --> 00:19:46,900 facilities and threats. But also, in many places for 382 00:19:46,900 --> 00:19:49,000 planning purposes, statistics are good enough. 383 00:19:49,000 --> 00:19:52,500 You just want to know in this particular area, what is the 384 00:19:52,500 --> 00:19:56,500 largest likely ground shaking the duration, one of the First, 385 00:19:56,500 --> 00:19:59,500 you select shaking in order to allow people to plan how to 386 00:19:59,500 --> 00:20:01,700 build buildings and so on. So there's a difference between 387 00:20:02,000 --> 00:20:05,200 being physically ripped apart by being astride the fault and 388 00:20:05,200 --> 00:20:07,200 being shaken. Because your next to the fold, 389 00:20:08,000 --> 00:20:09,700 how good are the historical records? 390 00:20:10,000 --> 00:20:12,800 Speaking of knowing what the impact is being in history in 391 00:20:12,800 --> 00:20:17,200 these high-risk areas and ironically, the risk areas which 392 00:20:17,200 --> 00:20:19,100 are certainly in Central Asia and the Alpine. 393 00:20:19,100 --> 00:20:22,500 Himalayan Central Asia region their historical record is much 394 00:20:22,500 --> 00:20:25,300 better than around the Pacific Rim so that the historical 395 00:20:25,300 --> 00:20:28,000 record in the right places at least between the Mediterranean 396 00:20:28,000 --> 00:20:30,300 and China go back 2,000 years or so. 397 00:20:30,700 --> 00:20:34,200 Whereas around the Pacific Rim, they've been inhabited by people 398 00:20:34,200 --> 00:20:37,800 writing records or keeping records for not very long, a few 399 00:20:37,800 --> 00:20:42,100 hundred years except for Japan but in Asia there's an enormous 400 00:20:42,100 --> 00:20:45,600 amount of information in the records of Empires. 401 00:20:45,600 --> 00:20:48,400 So the Byzantine Empire, the Ottoman Empire, the various 402 00:20:48,400 --> 00:20:52,600 Persian Empires and of course China were quite bureaucratic. 403 00:20:52,600 --> 00:20:56,700 They kept very good records of these things which Be an 404 00:20:56,700 --> 00:21:00,200 enormous goal by now. People go back and look at these 405 00:21:00,500 --> 00:21:03,600 counts kept by the bureaucracies of those time. 406 00:21:04,300 --> 00:21:06,400 It's a very, very scholarly activity. 407 00:21:06,400 --> 00:21:09,200 You have to be a fantastic linguist and historian just to 408 00:21:09,208 --> 00:21:12,200 get to first base, might be able to look at in this stuff and 409 00:21:12,200 --> 00:21:14,400 then you have to know we talked about in terms of the geology. 410 00:21:14,400 --> 00:21:17,000 The seismology engineering to know how to interpret. 411 00:21:17,000 --> 00:21:19,100 These records are very often exaggerated. 412 00:21:19,300 --> 00:21:23,500 They have particular styles of describing these calamities and 413 00:21:23,500 --> 00:21:25,600 they're not interested in things like ground motion, their 414 00:21:25,600 --> 00:21:29,000 interests Add in disruption to life and property and trade and 415 00:21:29,000 --> 00:21:31,000 so on. But you can interpret these 416 00:21:31,000 --> 00:21:33,300 things and they are extremely helpful. 417 00:21:33,500 --> 00:21:35,800 You have to get at that sort of information in these other 418 00:21:35,800 --> 00:21:39,600 countries should be settled this or for less Long in a more 419 00:21:39,600 --> 00:21:41,600 forensic. Detective kind of way by looking 420 00:21:41,600 --> 00:21:44,400 at the geological evidence, which is also possible that hard 421 00:21:44,400 --> 00:21:48,700 work, that's fascinating that work that needs to be done is 422 00:21:48,700 --> 00:21:53,500 both very much historical and sociological and really human in 423 00:21:53,500 --> 00:21:55,500 nature. Going back these thousands of 424 00:21:55,500 --> 00:21:59,600 years as I was on the other end very cutting-edge measuring 425 00:21:59,700 --> 00:22:03,200 precisely where Faults Are and using all the battery of 426 00:22:03,200 --> 00:22:06,500 techniques that we have today to figure out the present 427 00:22:06,500 --> 00:22:08,700 situation. It's very interesting it and 428 00:22:08,700 --> 00:22:10,800 there's a very good relationship between these routes. 429 00:22:11,000 --> 00:22:13,400 The historical work. Is an immense. 430 00:22:13,900 --> 00:22:16,300 Long-term work of scholarship is not the sort of thing. 431 00:22:16,300 --> 00:22:18,800 You achieve in a three-year research around it. 432 00:22:18,800 --> 00:22:21,500 Something we know people spend their life time, researching the 433 00:22:21,500 --> 00:22:24,100 history of earthquakes in Clash or something like that, and they 434 00:22:24,100 --> 00:22:26,200 come up with these historical earthquakes and then it It's the 435 00:22:26,208 --> 00:22:29,500 job of the modern scientists to then figure out. 436 00:22:29,500 --> 00:22:31,500 Okay, where was The Fault? Which was responsible for that 437 00:22:31,500 --> 00:22:33,200 earthquake? Can we actually find on the 438 00:22:33,200 --> 00:22:35,100 ground? What did it and the evidence 439 00:22:35,100 --> 00:22:38,000 that it really did do it for the whole thing together. 440 00:22:38,000 --> 00:22:40,800 So, there's a very close working relationship between these 441 00:22:40,800 --> 00:22:44,300 different groups. So, you live in Cambridge near 442 00:22:44,300 --> 00:22:49,500 London and I live in Boston. Are we in a safe area for my 443 00:22:49,500 --> 00:22:53,700 historical earthquake point of view in the sense that most of 444 00:22:53,700 --> 00:22:55,700 the earthquakes in the United States on the West Coast? 445 00:22:56,100 --> 00:22:58,900 And most of the earthquakes in Europe, by the Mediterranean 446 00:22:59,300 --> 00:23:02,100 heading Eastward, through Italy, Italy, Greece, and Turkey and so 447 00:23:02,100 --> 00:23:05,400 on, it doesn't mean we don't have any, we have some and lost 448 00:23:05,400 --> 00:23:07,200 of confidence have smaller earthquakes. 449 00:23:07,200 --> 00:23:09,400 We have any from in Cambridge. I remember from the last ten 450 00:23:09,400 --> 00:23:11,300 years, the couple of earthquakes, which are working 451 00:23:11,300 --> 00:23:13,900 people up there. It's very, very small by the 452 00:23:13,900 --> 00:23:16,300 standards of these proper earthquake countries. 453 00:23:16,300 --> 00:23:18,700 Could something people wouldn't get out of bed for, but they're 454 00:23:18,700 --> 00:23:20,700 not negligible, you have to watch out slightly. 455 00:23:20,700 --> 00:23:23,300 So for example, if you're building something which is very 456 00:23:23,300 --> 00:23:26,800 sensitive, like a nuclear power station, you really need to know 457 00:23:26,800 --> 00:23:30,500 what's going on. So you will have some assessment 458 00:23:30,500 --> 00:23:32,800 of what you think. The likely largest historical if 459 00:23:32,800 --> 00:23:36,500 B was or might be in the future and you will over designed to be 460 00:23:36,500 --> 00:23:40,000 safe in that. And so although people in 461 00:23:40,000 --> 00:23:42,800 England really don't think about it, breaks the electricity 462 00:23:42,800 --> 00:23:45,400 generating board who run the new capacitation, certainly do. 463 00:23:45,400 --> 00:23:49,400 And they've designed to in order to be conservative for what they 464 00:23:49,400 --> 00:23:51,200 think is the largest historical earthquakes. 465 00:23:51,500 --> 00:23:53,600 And the same is true, for example, needs Coast United 466 00:23:53,600 --> 00:23:55,900 States. And that's more interesting. 467 00:23:56,100 --> 00:24:00,200 Because actually you probably know that the Atlantic opens in 468 00:24:00,200 --> 00:24:04,100 the Jurassic 150 million years ago something and of course, the 469 00:24:04,100 --> 00:24:06,900 Appalachians is part of Scotland, essentially belonged 470 00:24:06,900 --> 00:24:09,800 up against Ireland and Scotland and you think it's just the 471 00:24:09,800 --> 00:24:11,900 other half of that situation in the North Sea. 472 00:24:12,200 --> 00:24:15,300 Now, in the UK and Northern Europe, we have of a long 473 00:24:15,300 --> 00:24:19,300 historical record mainly based on monastic record monastic 474 00:24:19,300 --> 00:24:21,900 Chronicles, which go back. Nearly two thousand years and 475 00:24:21,900 --> 00:24:25,500 there really has never been a really big earthquake in the UK 476 00:24:25,500 --> 00:24:28,400 and the We'll see in those last two thousand years, nothing 477 00:24:28,400 --> 00:24:31,500 awesome about Matthew 5 and a half which is really not going 478 00:24:31,500 --> 00:24:34,200 to cause trouble and you go to United States. 479 00:24:34,200 --> 00:24:36,600 The same is not true. It's been settled for a few 480 00:24:36,600 --> 00:24:39,200 hundred years at least a good historical record for the last 481 00:24:39,200 --> 00:24:42,300 few hundred years. And in that time, they've been 482 00:24:43,000 --> 00:24:45,900 several earthquakes quite a lot, bigger than anything in Europe 483 00:24:45,900 --> 00:24:48,600 in the last 2,000 years, and most famous was in Charleston. 484 00:24:48,600 --> 00:24:52,500 South Carolina in 1886, there's one in caveman, which is where 485 00:24:52,500 --> 00:24:55,900 you never be in Massachusetts. I think that was about 1750 486 00:24:56,100 --> 00:25:00,500 Five, but these were Manchu 6, Plus, and certainly bigger than 487 00:25:00,800 --> 00:25:03,100 anywhere in Northwest Europe, know why there should be that 488 00:25:03,100 --> 00:25:06,800 contrast between geologically. What if you like two halves of 489 00:25:06,800 --> 00:25:10,000 the same mirror, like the lad. You just broke split. 490 00:25:10,000 --> 00:25:12,900 The two in part. Why the American side should 491 00:25:12,900 --> 00:25:15,100 behave? So differently from the European 492 00:25:15,100 --> 00:25:17,500 side. No one really understands, but 493 00:25:17,800 --> 00:25:20,600 they do. And so you have to design for 494 00:25:20,600 --> 00:25:24,500 certainly big earthquakes and people are contemplating in 495 00:25:24,500 --> 00:25:27,100 Northwest Europe. Charleston earthquake did a lot 496 00:25:27,100 --> 00:25:29,300 of damage in South Carolina in 1880. 497 00:25:29,300 --> 00:25:32,900 See, it was a big deal and I just very well investigated and 498 00:25:32,900 --> 00:25:35,300 they were written up and there's a lot of detail about it. 499 00:25:35,900 --> 00:25:38,800 Didn't do too much because of course in those days in South 500 00:25:38,800 --> 00:25:42,300 Carolina, people mostly lived in wooden houses which were quite 501 00:25:42,300 --> 00:25:43,700 well built, they behave very well. 502 00:25:43,700 --> 00:25:46,300 Where does the best building material can happen in office? 503 00:25:46,300 --> 00:25:48,900 Europe would is an expensive building material so it's not 504 00:25:48,900 --> 00:25:52,100 that common. I'm going to ask you for my last 505 00:25:52,100 --> 00:25:55,900 question to be a little bit of forecaster, I know you do. 506 00:25:56,000 --> 00:25:59,300 Like to do that. But what I'm wondering is that 507 00:25:59,300 --> 00:26:02,800 even though the earthquakes that have happened in these dangerous 508 00:26:03,000 --> 00:26:07,400 belts in Central Asia and elsewhere are on time scales 509 00:26:07,400 --> 00:26:09,200 longer than an individual human life. 510 00:26:09,200 --> 00:26:12,500 So, there isn't a personal memory that perhaps makes people 511 00:26:12,700 --> 00:26:16,300 aware and attuned to the risk. One thing that has happened on a 512 00:26:16,300 --> 00:26:18,900 shorter time scale is this enormous growth in our 513 00:26:18,900 --> 00:26:20,900 scientific knowledge understanding which you've 514 00:26:20,900 --> 00:26:24,100 alluded to, in this talk? Do you have a sense as to 515 00:26:24,108 --> 00:26:27,700 whether this knowledge can be brought to bear to make this 516 00:26:27,900 --> 00:26:31,600 connection between cities and false, a little less fatal in 517 00:26:31,600 --> 00:26:35,000 the next few years, and decades while development proceeds in 518 00:26:35,008 --> 00:26:38,900 these countries, I hope so. That is an excellent question 519 00:26:38,900 --> 00:26:42,300 and that has occupied me the last 10 years. 520 00:26:43,000 --> 00:26:45,900 How do you actually turn the scientific knowledge into some 521 00:26:46,200 --> 00:26:49,400 increased Public Safety, and it's presumptuous to think the 522 00:26:49,400 --> 00:26:51,700 problem is just scientific. Of course, it's not it's to do 523 00:26:51,700 --> 00:26:53,700 with well. Health and Social logical 524 00:26:53,700 --> 00:26:56,200 conditions, cultural conditions, economics. 525 00:26:56,200 --> 00:26:59,400 All those kinds of things as well in the long run. 526 00:26:59,400 --> 00:27:02,200 You know, the only thing which works is education. 527 00:27:02,900 --> 00:27:06,100 People need to know what they're up against a need to know, it's 528 00:27:06,100 --> 00:27:09,800 not hopeless, right? That the great iniquity, I think 529 00:27:09,800 --> 00:27:11,900 is short-term earthquake prediction, which is like 530 00:27:11,900 --> 00:27:15,300 promise of a Panacea, a silver bullet if you allow the public 531 00:27:15,300 --> 00:27:17,900 to believe in it, it also allows them to think it's not their 532 00:27:17,900 --> 00:27:20,700 problem, a scientist will sort it out one day, they'll say the 533 00:27:20,700 --> 00:27:22,300 earthquakes can be Wednesday at 9:30. 534 00:27:22,300 --> 00:27:25,700 We I didn't have to do anything. That is faithful that kills lots 535 00:27:25,700 --> 00:27:29,200 of people that attitude and that's one of the roles of the 536 00:27:29,200 --> 00:27:31,800 scientists is to say, actually, that isn't going to happen. 537 00:27:32,300 --> 00:27:35,800 On the other hand, there are things you can do to make life 538 00:27:35,800 --> 00:27:38,600 safer big a on. There are lots of very switched 539 00:27:38,600 --> 00:27:42,900 on good people in those areas governments and ngos and Civic 540 00:27:42,900 --> 00:27:46,500 leaders who want to do the right thing and who care about this 541 00:27:46,800 --> 00:27:49,100 and they need help but the scientists can help them by 542 00:27:49,500 --> 00:27:52,500 helping them be realistic about what the public. 543 00:27:52,700 --> 00:27:55,000 He's going to face and they're in the number of such studies in 544 00:27:55,000 --> 00:27:58,900 countries like China and Nepal where you do a detailed study. 545 00:27:58,900 --> 00:28:01,900 You know this was our son incidentally in Kathmandu which 546 00:28:01,900 --> 00:28:05,500 had the big earthquake in 2015 before that earthquake and NGO 547 00:28:05,500 --> 00:28:08,500 had put together a study of what would happen if the previous 548 00:28:08,500 --> 00:28:12,800 earthquake which was 1934 in Katmandu repeated, right? 549 00:28:12,800 --> 00:28:16,200 And what would happen if that 1934 earthquake repeated today, 550 00:28:16,500 --> 00:28:18,900 given the so change in circumstances in terms of 551 00:28:19,200 --> 00:28:22,000 Greater population population density, the quality of 552 00:28:22,000 --> 00:28:24,700 buildings. The lifelines by which they mean 553 00:28:24,700 --> 00:28:28,400 things like roads and water supply and power Appliance on 554 00:28:28,900 --> 00:28:32,200 what would happen today and they did that study and it wasn't 555 00:28:32,200 --> 00:28:36,100 some arm wavy publicity stunt. It was two years of really hard, 556 00:28:36,200 --> 00:28:39,900 scientific evaluation of what that earthquake was in, 1934, 557 00:28:39,900 --> 00:28:42,400 what caused it, where the fault was that moved? 558 00:28:42,400 --> 00:28:44,600 What was the ground shaking? What would that ground-shaking 559 00:28:44,600 --> 00:28:47,400 do today? And they publish it as a story, 560 00:28:47,400 --> 00:28:51,500 almost as a cartoon picture book illustrating the consequences of 561 00:28:51,500 --> 00:28:53,900 such an earthquake for a Family in Katmandu. 562 00:28:54,000 --> 00:28:56,600 So the father would be working the other side of the city, the 563 00:28:56,600 --> 00:28:59,200 bridges over the river, would have been collapsed so he would 564 00:28:59,200 --> 00:29:00,900 take him two days to get home in Wild. 565 00:29:00,900 --> 00:29:03,000 What do people do? They're going to camp on the 566 00:29:03,000 --> 00:29:05,200 football field. They have 23 Days In and Out of 567 00:29:05,200 --> 00:29:09,200 Water and so on and so on time. And this was a story to get 568 00:29:09,200 --> 00:29:11,000 people to concentrate their minds and what would actually 569 00:29:11,000 --> 00:29:13,200 happen. And then in 2015, the earthquake 570 00:29:13,200 --> 00:29:16,400 did happen and you could read this story book and more. 571 00:29:16,400 --> 00:29:19,000 Let's turn over the page and say this is what's gonna happen 572 00:29:19,000 --> 00:29:22,000 tomorrow and it more or less. Did they had a lucky Escape? 573 00:29:22,000 --> 00:29:24,800 Because you're okay. Wasn't quite as big as 1934. 574 00:29:25,100 --> 00:29:29,400 So instead of getting 100,000 people about 10,000 people James 575 00:29:29,400 --> 00:29:31,100 Jackson, thank you very much.