1 00:00:00,600 --> 00:00:03,920 Speaker 1: Hey, Welcome to Sign Stuff, a production of iHeartRadio. My 2 00:00:04,040 --> 00:00:06,480 Speaker 1: name is Jorge cham and today we are digging deep 3 00:00:06,480 --> 00:00:09,319 Speaker 1: into the question what happens if you dig a hole 4 00:00:09,520 --> 00:00:12,239 Speaker 1: to the center of the earth. It's a question most 5 00:00:12,240 --> 00:00:14,080 Speaker 1: of us have asked when we were making a hole 6 00:00:14,080 --> 00:00:16,600 Speaker 1: in our yards or at the beach. Is it actually 7 00:00:16,640 --> 00:00:18,919 Speaker 1: possible to dig all the way through? Or would you 8 00:00:19,000 --> 00:00:21,400 Speaker 1: perish in the process. We're going to talk to people 9 00:00:21,440 --> 00:00:24,160 Speaker 1: whose jobs it is to dig the deepest holes humans 10 00:00:24,200 --> 00:00:26,200 Speaker 1: have ever dug, and we're going to take a journey 11 00:00:26,239 --> 00:00:28,920 Speaker 1: with one of them to see how far we can get. 12 00:00:29,360 --> 00:00:32,320 Speaker 1: So let's dive in and answer the question what happens 13 00:00:32,400 --> 00:00:34,640 Speaker 1: if you dig a hole to the center of the Earth. 14 00:00:35,080 --> 00:00:44,240 Speaker 1: I promise it won't be a bore. Welcome to sign Stuff. Okay, 15 00:00:44,600 --> 00:00:48,239 Speaker 1: here's a list of the top five deepest holes humans 16 00:00:48,280 --> 00:00:53,600 Speaker 1: have ever dug. Numbers five through three are oil wheels 17 00:00:53,760 --> 00:00:56,000 Speaker 1: that were dug in the Gulf of Mexico or at 18 00:00:56,080 --> 00:00:58,040 Speaker 1: least what do you speak called the Gulf of Mexico 19 00:00:58,320 --> 00:01:01,240 Speaker 1: near the coast of Texas and Louzy. They have names 20 00:01:01,280 --> 00:01:04,399 Speaker 1: like two to five, that zero one or GC five 21 00:01:04,480 --> 00:01:06,920 Speaker 1: one two number one, BP two and they go down 22 00:01:06,959 --> 00:01:09,800 Speaker 1: to about the same depth, which is around ten and 23 00:01:09,840 --> 00:01:14,720 Speaker 1: a half kilometers straight down. The second deepest hole ever 24 00:01:14,800 --> 00:01:17,920 Speaker 1: dug is called tiber Kse one two, and it's also 25 00:01:18,000 --> 00:01:20,520 Speaker 1: an oil well. But notably it was dug in two 26 00:01:20,560 --> 00:01:24,520 Speaker 1: thousand and nine by deep Water Horizon, the powerful digging 27 00:01:24,560 --> 00:01:27,119 Speaker 1: rig that seven months later, while trying to drill its 28 00:01:27,240 --> 00:01:30,800 Speaker 1: next hole, exploded and caused the largest oil spill in 29 00:01:30,880 --> 00:01:34,000 Speaker 1: human history. Tiber Kse one two is a hole that 30 00:01:34,080 --> 00:01:38,120 Speaker 1: goes down ten kilometers six hundred and eighty three meters 31 00:01:38,240 --> 00:01:42,120 Speaker 1: straight down. But the deepest hole ever dug by humans 32 00:01:42,440 --> 00:01:45,520 Speaker 1: is a little bit deeper. It's called SG three or 33 00:01:45,560 --> 00:01:48,280 Speaker 1: the coalis Super Deep borehole, and it was dug over 34 00:01:48,320 --> 00:01:51,960 Speaker 1: a period of twenty years as a classified, top secret 35 00:01:52,040 --> 00:01:55,320 Speaker 1: research project by Russian scientists. It's in the part of 36 00:01:55,400 --> 00:01:59,320 Speaker 1: Russia that borders Norway and Finland, in the Scandinavian Peninsula. 37 00:01:59,480 --> 00:02:02,120 Speaker 1: The hole is about nine inches wide and it goes 38 00:02:02,120 --> 00:02:05,360 Speaker 1: down to a death of twelve kilometers two hundred and 39 00:02:05,440 --> 00:02:10,440 Speaker 1: sixty two meters or about twenty eight Empire state buildings 40 00:02:10,560 --> 00:02:15,280 Speaker 1: stacked on top of each other. Now, these are really 41 00:02:15,280 --> 00:02:18,360 Speaker 1: deep holes in human terms, but they're actually kind of 42 00:02:18,360 --> 00:02:21,359 Speaker 1: shallow if you compare them to the size of the Earth. 43 00:02:21,720 --> 00:02:25,079 Speaker 1: The Earth is twelve thousand, seven hundred and fifty six 44 00:02:25,160 --> 00:02:28,600 Speaker 1: kilometers wide, which means the deepest holes we've ever dug 45 00:02:28,919 --> 00:02:32,760 Speaker 1: are barely zero point one percent of the way through. 46 00:02:33,520 --> 00:02:36,400 Speaker 1: So the main questions we're answering today are why did 47 00:02:36,400 --> 00:02:40,120 Speaker 1: the people making these holes stop digging, what would have 48 00:02:40,160 --> 00:02:43,079 Speaker 1: happened if they had kept going? And is it even 49 00:02:43,240 --> 00:02:46,320 Speaker 1: possible to get to the center of the Earth. To 50 00:02:46,320 --> 00:02:48,880 Speaker 1: answer these questions, we're going to do three things. We're 51 00:02:48,880 --> 00:02:51,480 Speaker 1: going to find out why so hard to dig a 52 00:02:51,520 --> 00:02:53,680 Speaker 1: really deep hole, Then we're going to talk about the 53 00:02:53,720 --> 00:02:57,160 Speaker 1: cool technology people are using to dig deeper and deeper, 54 00:02:57,560 --> 00:03:00,000 Speaker 1: and then at the end we'll ask experts if it's 55 00:03:00,000 --> 00:03:02,760 Speaker 1: it's even possible to dig all the way to the 56 00:03:02,760 --> 00:03:06,200 Speaker 1: center of the earth. Okay, So the first thing I 57 00:03:06,240 --> 00:03:08,840 Speaker 1: did was I reached out to people whose job it 58 00:03:08,919 --> 00:03:12,320 Speaker 1: is to dig super deep holes. The first person I 59 00:03:12,360 --> 00:03:15,960 Speaker 1: talked to was doctor Eric van Ord, the professor in 60 00:03:16,000 --> 00:03:20,040 Speaker 1: the Department of Petroleum and Geosystems Engineering the University of 61 00:03:20,080 --> 00:03:23,080 Speaker 1: Texas at Austin, and he is an expert in drilling 62 00:03:23,360 --> 00:03:28,040 Speaker 1: hydraulic fracturing and geomechanics. I basically asked him point blank, 63 00:03:28,639 --> 00:03:31,720 Speaker 1: why is it so hard to dig a really deep hole? 64 00:03:32,320 --> 00:03:36,160 Speaker 1: So here's my conversation with doctor Eric van Ort. Well, 65 00:03:36,160 --> 00:03:38,840 Speaker 1: thank you so much, professor van Ord for joining us. 66 00:03:39,320 --> 00:03:40,160 Speaker 2: Happy to be here. 67 00:03:40,320 --> 00:03:43,640 Speaker 1: Now. You're expert in drilling engineering, and so I have 68 00:03:43,680 --> 00:03:45,320 Speaker 1: a lot of questions for you that I really want 69 00:03:45,360 --> 00:03:49,760 Speaker 1: to drill into but intended. Yeah, can you talk to 70 00:03:49,880 --> 00:03:51,520 Speaker 1: us a little bit about what are some of the 71 00:03:51,680 --> 00:03:54,280 Speaker 1: challenges that you run into when you try to drill 72 00:03:54,400 --> 00:03:55,200 Speaker 1: into the ground. 73 00:03:55,640 --> 00:03:58,600 Speaker 2: Well, we drill into the ground to explore and produce 74 00:03:58,680 --> 00:04:02,920 Speaker 2: oil and gosh, but also to explore and produce geothermal heat, 75 00:04:03,080 --> 00:04:07,760 Speaker 2: to store CO two and waste underground. Sometimes even build 76 00:04:07,800 --> 00:04:11,280 Speaker 2: repositories for nuclear waste that could be stored underground. So 77 00:04:11,400 --> 00:04:16,440 Speaker 2: different wells have different challenges. Formations are unconsolidated. That means 78 00:04:16,480 --> 00:04:19,200 Speaker 2: that they're not holding together right as a problem with 79 00:04:19,279 --> 00:04:22,440 Speaker 2: the stability of the well board that you could sometimes see. 80 00:04:22,880 --> 00:04:25,840 Speaker 1: Okay, the first challenge in digging a really deep hole 81 00:04:26,000 --> 00:04:28,440 Speaker 1: is that deep holes don't want to stay holes for 82 00:04:28,600 --> 00:04:32,480 Speaker 1: very long. They tend to collapse. Like deferend Or compares 83 00:04:32,520 --> 00:04:34,440 Speaker 1: it to trying to dig a hole in the sand 84 00:04:34,600 --> 00:04:35,200 Speaker 1: at the beach. 85 00:04:36,240 --> 00:04:39,159 Speaker 2: If you've ever been digging a hole on the beach 86 00:04:39,440 --> 00:04:41,800 Speaker 2: as a kid, you get very frustrated, right, because will 87 00:04:42,120 --> 00:04:44,240 Speaker 2: you want to drill the deepest hole possible, right, go 88 00:04:44,360 --> 00:04:47,240 Speaker 2: to the center of the earth, right, and you're thwarted 89 00:04:47,279 --> 00:04:49,279 Speaker 2: by the fact that you can only get to a 90 00:04:49,279 --> 00:04:51,599 Speaker 2: certain depth and no deeper right. 91 00:04:51,760 --> 00:04:52,039 Speaker 3: Right. 92 00:04:52,240 --> 00:04:53,880 Speaker 1: So that happens even in solid rock. 93 00:04:54,200 --> 00:04:56,919 Speaker 2: Even in solid rock, I mean, when you drill a borehole, 94 00:04:57,120 --> 00:04:59,560 Speaker 2: what the Earth wants to do is close that borehole. 95 00:04:59,600 --> 00:05:02,239 Speaker 1: Again, what do you mean that nature wants to close 96 00:05:02,279 --> 00:05:02,760 Speaker 1: the hole? 97 00:05:03,120 --> 00:05:06,080 Speaker 2: Well, in the earth, right, you have stresses acting on 98 00:05:06,120 --> 00:05:08,080 Speaker 2: the borehole. The weight of the rock on top is 99 00:05:08,080 --> 00:05:11,160 Speaker 2: the vertical stress, and then there are horizontal stresses because 100 00:05:11,200 --> 00:05:15,080 Speaker 2: of tectonic movements, and those stresses act on the borehole 101 00:05:15,200 --> 00:05:17,880 Speaker 2: and they would collapse the borehole and you would lose 102 00:05:17,880 --> 00:05:18,640 Speaker 2: it eventually. 103 00:05:19,400 --> 00:05:21,680 Speaker 1: So, just like digging a hole in the sand at 104 00:05:21,680 --> 00:05:26,440 Speaker 1: the beach, eventually deep holes collapse. Even when you're digging 105 00:05:26,520 --> 00:05:29,800 Speaker 1: through solid rock. Eventually, the sheer weight of all the 106 00:05:29,920 --> 00:05:32,359 Speaker 1: rock around your hole is going to want to close 107 00:05:32,600 --> 00:05:35,919 Speaker 1: your hole. There is a clever solution for that. 108 00:05:37,040 --> 00:05:39,600 Speaker 2: So we need to stabilize the hole as we're drilling it. 109 00:05:39,800 --> 00:05:43,400 Speaker 2: We typically do that by circulating a drilling fluid that 110 00:05:43,600 --> 00:05:47,480 Speaker 2: provides kind of hydrostatic pressure to keep the borehole open 111 00:05:47,800 --> 00:05:48,440 Speaker 2: it meaning. 112 00:05:48,200 --> 00:05:51,360 Speaker 1: You fill it with like water or oil. 113 00:05:51,600 --> 00:05:54,240 Speaker 2: Water or oil that we can change the density of. 114 00:05:54,360 --> 00:05:56,600 Speaker 2: So we have the ability to change the density and 115 00:05:56,640 --> 00:06:00,159 Speaker 2: thereby the hydrostatic pressure that is being exerted onto the 116 00:06:00,160 --> 00:06:01,039 Speaker 2: poorhole wall. 117 00:06:01,120 --> 00:06:03,240 Speaker 1: And that prevents the whole from caving in. 118 00:06:03,440 --> 00:06:05,120 Speaker 2: That prevents the hole from collapsing. 119 00:06:06,400 --> 00:06:09,200 Speaker 1: The other thing that makes being really deep whole heart 120 00:06:09,520 --> 00:06:10,440 Speaker 1: is temperature. 121 00:06:11,120 --> 00:06:14,760 Speaker 2: In the center of the Earth, the temperature is six 122 00:06:14,839 --> 00:06:18,120 Speaker 2: thousand kelvin. It's the same temperature as the surface of 123 00:06:18,160 --> 00:06:21,320 Speaker 2: the Sun. The sun, of course, at its core is 124 00:06:21,480 --> 00:06:24,560 Speaker 2: millions of degreas, but the surface of the Sun is 125 00:06:24,720 --> 00:06:28,160 Speaker 2: about six thousand calvin And that's also the temperature in 126 00:06:28,200 --> 00:06:29,279 Speaker 2: the center of the Earth. 127 00:06:29,720 --> 00:06:30,240 Speaker 1: Wow. 128 00:06:30,279 --> 00:06:33,440 Speaker 2: And then there's a temperature gradient going to the outside. 129 00:06:33,000 --> 00:06:35,240 Speaker 1: Meaning six thousand degrees of the center. But it gets 130 00:06:35,279 --> 00:06:37,000 Speaker 1: cooler as you go up to the surface. 131 00:06:37,200 --> 00:06:39,680 Speaker 2: Yep. But the deeper you go into the Earth, the 132 00:06:39,720 --> 00:06:40,680 Speaker 2: higher the temperature. 133 00:06:41,120 --> 00:06:42,840 Speaker 1: And why is the earth hot inside. 134 00:06:42,960 --> 00:06:45,760 Speaker 2: It's because of the formation of the Earth. So what 135 00:06:45,800 --> 00:06:49,039 Speaker 2: we call primordial heat, heat that got trapped when the 136 00:06:49,120 --> 00:06:49,840 Speaker 2: Earth formed. 137 00:06:50,839 --> 00:06:53,440 Speaker 1: So the Earth is hot inside, which is a little 138 00:06:53,440 --> 00:06:56,000 Speaker 1: odd to think about because which is the giant rock 139 00:06:56,160 --> 00:06:59,160 Speaker 1: floating out in the coldness of space? So where did 140 00:06:59,200 --> 00:07:02,440 Speaker 1: all that heat come from? Well, it came from two places, 141 00:07:02,520 --> 00:07:05,359 Speaker 1: according to doctor Van Ord. Number one, when the Earth 142 00:07:05,440 --> 00:07:08,560 Speaker 1: was formed, meaning when all those rocks and dust in 143 00:07:08,600 --> 00:07:11,679 Speaker 1: the early Solar systems scrunched together to form the Earth. 144 00:07:12,000 --> 00:07:15,480 Speaker 1: The scrunching generated a lot of heat, and also the 145 00:07:15,520 --> 00:07:18,880 Speaker 1: Earth kick getting hit by asteroids and giant rocks that 146 00:07:18,920 --> 00:07:22,040 Speaker 1: were zooming around the early Solar System. It's sort of 147 00:07:22,040 --> 00:07:23,880 Speaker 1: like if you take a mass of clay and you 148 00:07:23,920 --> 00:07:26,840 Speaker 1: beat it with your hands that were mallet Eventually it 149 00:07:26,920 --> 00:07:30,000 Speaker 1: heats up, and that's what happened to the Earth. In fact, 150 00:07:30,040 --> 00:07:32,440 Speaker 1: at some point the Earth was so hot it was 151 00:07:32,560 --> 00:07:36,600 Speaker 1: just a big ball of lava. And number two, the 152 00:07:36,680 --> 00:07:41,160 Speaker 1: Earth is also hot because there are radioactive elements inside 153 00:07:41,160 --> 00:07:46,080 Speaker 1: the Earth, like uranium and plutonium that are decaying, essentially 154 00:07:46,360 --> 00:07:49,960 Speaker 1: nuking the Earth from the inside. So as you dig deeper, 155 00:07:50,200 --> 00:07:53,760 Speaker 1: it gets hotter. How hot here's how doctor Van Ord 156 00:07:53,960 --> 00:07:54,520 Speaker 1: puts it. 157 00:07:55,360 --> 00:07:57,880 Speaker 2: The Earth is a really good insulator. The amount of 158 00:07:57,920 --> 00:08:02,880 Speaker 2: heat that it chops is obsolutely massive. It's an amazing 159 00:08:02,920 --> 00:08:07,440 Speaker 2: amount of heat is phenomenal. And even though Earth radiates 160 00:08:07,600 --> 00:08:10,320 Speaker 2: heat into cold space all the time, to give you 161 00:08:10,360 --> 00:08:13,080 Speaker 2: a comparison, if you look at all the energy that 162 00:08:13,200 --> 00:08:16,240 Speaker 2: humanity uses around the world at any given point in time, 163 00:08:16,280 --> 00:08:20,280 Speaker 2: it's about fifteen tertra wats, and the Earth radiates into 164 00:08:20,320 --> 00:08:24,600 Speaker 2: the space about fifty terrawatts of heat energy all the time. 165 00:08:24,720 --> 00:08:25,240 Speaker 1: Oh wow. 166 00:08:25,400 --> 00:08:28,720 Speaker 2: Even then with that phenomenal amount of energy that it loses, 167 00:08:29,120 --> 00:08:32,040 Speaker 2: even over forty billion years, it has hardly lost any 168 00:08:32,080 --> 00:08:33,920 Speaker 2: significant amount of heat. 169 00:08:34,520 --> 00:08:36,800 Speaker 1: So it's like we have a little sun almost at 170 00:08:36,800 --> 00:08:37,800 Speaker 1: the center of the Earth. 171 00:08:38,720 --> 00:08:41,880 Speaker 2: So we call that kind of the heat beneath our feet. 172 00:08:42,520 --> 00:08:45,079 Speaker 1: What that means is that as you dig deeper, it 173 00:08:45,120 --> 00:08:48,200 Speaker 1: gets horder. How hard it gets depends on where you 174 00:08:48,240 --> 00:08:51,480 Speaker 1: make the hole, but generally speaking, near the surface, digging 175 00:08:51,480 --> 00:08:55,160 Speaker 1: a hole gets harder about fifteen degrees celsius for each 176 00:08:55,280 --> 00:08:59,240 Speaker 1: kilometer you go down. So at the Cola super borehole 177 00:08:59,360 --> 00:09:02,240 Speaker 1: in Russia, the deepest humans I've ever dug, they reach 178 00:09:02,320 --> 00:09:06,200 Speaker 1: temperatures of one hundred and eighty degrees celsius or around 179 00:09:06,200 --> 00:09:08,880 Speaker 1: three hundred and fifty six fahrenheit, which is around the 180 00:09:08,880 --> 00:09:13,319 Speaker 1: temperature you would say you're oven two to cook roast beef. Now, 181 00:09:13,360 --> 00:09:16,120 Speaker 1: those are the two main reasons digging hole is hard. 182 00:09:16,480 --> 00:09:19,160 Speaker 1: There are other reasons too, like pressure. 183 00:09:20,280 --> 00:09:22,280 Speaker 2: We need to deal with not only hort temperatures but 184 00:09:22,320 --> 00:09:25,720 Speaker 2: also high pressures. So not only does the temperature get higher, 185 00:09:25,800 --> 00:09:27,280 Speaker 2: the pressure gets higher as well. 186 00:09:27,880 --> 00:09:32,160 Speaker 1: So whatever you put down there basically gets squished. Yeah. 187 00:09:32,400 --> 00:09:35,200 Speaker 2: As you get deeper and deeper and the temperatures get higher, 188 00:09:35,240 --> 00:09:38,280 Speaker 2: and the pressures get higher, and the rocks get harder. 189 00:09:38,640 --> 00:09:40,400 Speaker 1: Waight the rocks get harder. 190 00:09:40,280 --> 00:09:43,800 Speaker 2: Yeah, because of again that weight of the overlying informations. 191 00:09:43,840 --> 00:09:46,520 Speaker 2: The rocks start to consolidate, and then they also start 192 00:09:46,559 --> 00:09:49,080 Speaker 2: to change under the influence of pressure and temperature. 193 00:09:49,679 --> 00:09:51,240 Speaker 1: Oh, they get more dense. 194 00:09:51,640 --> 00:09:53,959 Speaker 2: Yeah, really hard stuff to drill. 195 00:09:55,000 --> 00:09:58,079 Speaker 1: Also, when you're drilling under the ground, you're kind of 196 00:09:58,160 --> 00:10:03,160 Speaker 1: drilling blind. Example, you might accidentally hit some lava. 197 00:10:04,440 --> 00:10:09,320 Speaker 2: That's generally not good, but it has happened. In Iceland, 198 00:10:09,320 --> 00:10:12,640 Speaker 2: they drilled a well called the ice Iceland Deep Drilling 199 00:10:12,679 --> 00:10:17,439 Speaker 2: Project at a price called Kravla. They actually drilled into 200 00:10:17,600 --> 00:10:19,640 Speaker 2: an active volcano, So they actually drilled into a. 201 00:10:19,600 --> 00:10:22,120 Speaker 1: Magma chamber on purpose or by accident. 202 00:10:22,240 --> 00:10:26,680 Speaker 2: By accident, so they encountered a nine hundred degrees centigrade 203 00:10:26,920 --> 00:10:30,319 Speaker 2: temperatures well over two thousand degrees fahrenheit. There's a ridiculous 204 00:10:30,360 --> 00:10:34,520 Speaker 2: amount of temperature that we saw there. Now, luckily the 205 00:10:34,679 --> 00:10:37,760 Speaker 2: chamber was not pressurized and low and behold, they were 206 00:10:37,800 --> 00:10:41,560 Speaker 2: able to temporarily keep that hole and actually briefly turn 207 00:10:41,600 --> 00:10:44,800 Speaker 2: it into a geothermal well which was producing kind of 208 00:10:44,960 --> 00:10:47,760 Speaker 2: thirty five megawatts of power. Wow, and you can run 209 00:10:47,800 --> 00:10:50,439 Speaker 2: a small city of that, right, It's pretty amazing. 210 00:10:51,120 --> 00:10:53,800 Speaker 1: And then, of course what makes digging a really deep 211 00:10:53,840 --> 00:10:57,240 Speaker 1: hole heart is that you have to dig through solid rock. 212 00:10:57,720 --> 00:11:00,320 Speaker 1: So when we come back, we'll talk to a different 213 00:11:00,320 --> 00:11:04,280 Speaker 1: professional hole digger about the different technologies we use to 214 00:11:04,400 --> 00:11:10,559 Speaker 1: dig through rock. They involve diamonds, lasers, and microwaves. Stay 215 00:11:10,600 --> 00:11:22,840 Speaker 1: with us, you're listening to sign stuff. Hey, welcome back. Okay, 216 00:11:23,080 --> 00:11:26,559 Speaker 1: we talked about why drilling a deep hole is hard, 217 00:11:26,679 --> 00:11:28,680 Speaker 1: and in the next section we're going to talk about 218 00:11:28,679 --> 00:11:31,400 Speaker 1: whether it's possible to dig a hole to the center 219 00:11:31,440 --> 00:11:33,839 Speaker 1: of the Earth. But first I was curious to learn 220 00:11:34,040 --> 00:11:37,400 Speaker 1: how exactly you dig a hole that deep, what's the 221 00:11:37,480 --> 00:11:40,800 Speaker 1: technology you use? And let me just preview this by saying, 222 00:11:40,840 --> 00:11:45,040 Speaker 1: there are going to be lasers involved, big lasers to 223 00:11:45,080 --> 00:11:47,280 Speaker 1: guide us through this. I talked to another person whose 224 00:11:47,320 --> 00:11:49,200 Speaker 1: job it is to dig deep holes. 225 00:11:49,880 --> 00:11:52,400 Speaker 3: So my name is Roman Short. I'm associate professor here 226 00:11:52,400 --> 00:11:54,560 Speaker 3: at Texas A and M University. I work a lot 227 00:11:54,640 --> 00:11:58,600 Speaker 3: in drilling, drilling automation optimization for subservice energy. 228 00:11:58,679 --> 00:12:00,800 Speaker 1: Well, thanks for joining us, doctor sh So how do 229 00:12:00,880 --> 00:12:03,120 Speaker 1: you drill a hole in the ground through rock. 230 00:12:03,480 --> 00:12:05,719 Speaker 3: The way that you typically do it? You need a 231 00:12:05,760 --> 00:12:08,280 Speaker 3: really big drill, A drilling rig comes on site and 232 00:12:08,320 --> 00:12:10,280 Speaker 3: same thing like that drill bit that you're using in 233 00:12:10,320 --> 00:12:12,960 Speaker 3: your wall. Just imagine a really long drill bit. Tap 234 00:12:13,080 --> 00:12:16,200 Speaker 3: top start rotating it, the bottom rotates eventually, and then 235 00:12:16,240 --> 00:12:18,160 Speaker 3: you lower down until you hit the ground and then 236 00:12:18,200 --> 00:12:19,480 Speaker 3: the bit is a failing rock. 237 00:12:20,400 --> 00:12:24,080 Speaker 1: Yeah, it's literally just the drill, but imagine one that's 238 00:12:24,200 --> 00:12:27,240 Speaker 1: nine to ten inches wide and that sits at the 239 00:12:27,360 --> 00:12:31,520 Speaker 1: end of a ten kilometer long steel rod. Now I 240 00:12:31,559 --> 00:12:33,800 Speaker 1: have a drill at home, and when I drill, the 241 00:12:33,880 --> 00:12:37,080 Speaker 1: bits that get cut spiral up the drill and usually 242 00:12:37,120 --> 00:12:40,520 Speaker 1: fall to the ground. But in a ten kilometer deep hole, 243 00:12:41,000 --> 00:12:44,160 Speaker 1: what happens to all the stuff you drill out? Here's 244 00:12:44,200 --> 00:12:45,360 Speaker 1: what doctor Shore said. 245 00:12:46,200 --> 00:12:48,840 Speaker 3: That's another use for that drilling fluid. So that water 246 00:12:49,160 --> 00:12:51,559 Speaker 3: you pump it down the drill pipe comes out the 247 00:12:51,640 --> 00:12:54,440 Speaker 3: drill bit, and it captures all those pieces of rock 248 00:12:54,640 --> 00:12:56,840 Speaker 3: and then moves them back up to the surface. So 249 00:12:56,920 --> 00:13:00,200 Speaker 3: you're helping clean this well bore using this fluid. I'll 250 00:13:00,200 --> 00:13:02,400 Speaker 3: also provide you stability for that whole. So it's like 251 00:13:02,480 --> 00:13:04,560 Speaker 3: kind of cool how that drilling mud use does build 252 00:13:04,559 --> 00:13:05,120 Speaker 3: things at once. 253 00:13:06,080 --> 00:13:07,960 Speaker 1: Okay, I know that's the second time we mentioned this 254 00:13:08,040 --> 00:13:12,559 Speaker 1: drilling fluid, but trust me, it's going to be important later. Now, 255 00:13:12,679 --> 00:13:14,400 Speaker 1: is it a drill bit like the drill I have 256 00:13:14,520 --> 00:13:18,120 Speaker 1: at home, like the spiral metal thing, or it's similar. 257 00:13:18,720 --> 00:13:21,600 Speaker 3: So rock is a little bit harder than the dry 258 00:13:21,679 --> 00:13:23,600 Speaker 3: wall or the word that you typically drill through. So 259 00:13:23,720 --> 00:13:26,320 Speaker 3: a lot of these rodary drill bits now use that 260 00:13:26,360 --> 00:13:30,000 Speaker 3: technology called polycrystaline diamond. So there's these little tiny diamond 261 00:13:30,000 --> 00:13:34,280 Speaker 3: cutters that are embedded into this bigger spiral. Effectively, you 262 00:13:34,320 --> 00:13:36,760 Speaker 3: can think of your spiral drill bit. Just think of that, 263 00:13:36,880 --> 00:13:39,440 Speaker 3: but much larger, and you have little tiny diamond cutters 264 00:13:39,480 --> 00:13:41,960 Speaker 3: along the edges of each of those teeth, so they 265 00:13:41,960 --> 00:13:44,120 Speaker 3: act like teeth as they're rotating. 266 00:13:44,880 --> 00:13:48,480 Speaker 1: Yes, that's right. To dig to rock, you use diamonds. 267 00:13:48,960 --> 00:13:51,440 Speaker 3: Yeah, so it's an artificial diamond. You put that under 268 00:13:51,480 --> 00:13:54,840 Speaker 3: ground and that can drill for hundreds to thousands of feet, 269 00:13:55,040 --> 00:13:56,439 Speaker 3: sometimes even miles. 270 00:13:56,800 --> 00:13:59,360 Speaker 1: Yeah, diamonds are pretty cool. But contrary to what they 271 00:13:59,400 --> 00:14:03,120 Speaker 1: say or not forever, the problem with the drill, doctor 272 00:14:03,120 --> 00:14:06,400 Speaker 1: Shore says is that they wear out, even the ones 273 00:14:06,480 --> 00:14:09,679 Speaker 1: with diamonds, and replacing something at the bottom of a 274 00:14:09,720 --> 00:14:14,400 Speaker 1: ten kilometer hole is not easy. So scientists of engineers 275 00:14:14,440 --> 00:14:17,240 Speaker 1: have been coming up with new technologies to dig or 276 00:14:17,320 --> 00:14:21,000 Speaker 1: blast their way through rock. And you said there's other 277 00:14:21,040 --> 00:14:24,960 Speaker 1: technologies like using lasers. Yep, you describe some of those exactly. 278 00:14:25,040 --> 00:14:26,960 Speaker 3: So what I've been talking about so far is called 279 00:14:27,000 --> 00:14:31,040 Speaker 3: rotary drilling. Other technologies that people have been looking at 280 00:14:31,280 --> 00:14:35,280 Speaker 3: is can you use that's say, a microwave to literally 281 00:14:35,440 --> 00:14:38,160 Speaker 3: firmly degrade the rock and melt it, burn it out 282 00:14:38,160 --> 00:14:38,520 Speaker 3: of the way. 283 00:14:39,320 --> 00:14:43,160 Speaker 1: Wait, just shoot, just shoot the rock with Yeah. 284 00:14:43,080 --> 00:14:46,600 Speaker 3: Just with the microwave being you're just like not quite 285 00:14:46,680 --> 00:14:49,360 Speaker 3: star star trek Pew pew. But it's the same journal. Yes, 286 00:14:49,400 --> 00:14:52,240 Speaker 3: like you just imagine this energy being forced pointed at 287 00:14:52,280 --> 00:14:52,640 Speaker 3: this rock. 288 00:14:53,160 --> 00:14:55,880 Speaker 1: What that works? Like if I shoot a microwave at 289 00:14:55,880 --> 00:14:58,880 Speaker 1: a rock, it'll actually disintegrate eventually. 290 00:14:59,040 --> 00:15:01,360 Speaker 3: Yes, it takes a lot of energy, but it does. 291 00:15:01,880 --> 00:15:04,000 Speaker 3: It turns into vapor. So it just turns into a 292 00:15:04,040 --> 00:15:06,520 Speaker 3: gas and then you can if you just circulate air 293 00:15:06,720 --> 00:15:10,200 Speaker 3: just comes out as as a gasified. 294 00:15:09,720 --> 00:15:14,520 Speaker 1: Rock vaporized rock. Whoa, Because the microwaves are hitting the 295 00:15:14,600 --> 00:15:18,600 Speaker 1: rock and that's basically blowing off the rock atoms from 296 00:15:18,640 --> 00:15:19,400 Speaker 1: the surface. 297 00:15:19,320 --> 00:15:21,560 Speaker 3: So the atoms themselves stay constant. I think it's breaking 298 00:15:21,560 --> 00:15:24,200 Speaker 3: a lot of the molecular bonds and also some of 299 00:15:24,240 --> 00:15:27,000 Speaker 3: the weaker bonds that are between let's say a different 300 00:15:27,040 --> 00:15:28,320 Speaker 3: molecules different grains. 301 00:15:28,920 --> 00:15:32,240 Speaker 1: So one technology they're exploring is to zap the rock 302 00:15:32,400 --> 00:15:34,760 Speaker 1: with a microwave, just like the one you use at 303 00:15:34,760 --> 00:15:38,000 Speaker 1: home to reheat your food, well not quite like the 304 00:15:38,000 --> 00:15:38,800 Speaker 1: one in your kitchen. 305 00:15:39,360 --> 00:15:41,640 Speaker 3: So but the problem with this is how do you 306 00:15:41,760 --> 00:15:46,320 Speaker 3: generate microwaves that are high enough energy close enough to 307 00:15:46,480 --> 00:15:50,680 Speaker 3: that rock surface. So, like your microwave at home is 308 00:15:50,720 --> 00:15:53,960 Speaker 3: a kilowat and that's what you use to heat your food. 309 00:15:54,240 --> 00:15:57,080 Speaker 3: In order to melt rock, you need a thousand times 310 00:15:57,080 --> 00:16:00,760 Speaker 3: more power, give or take like a million what, yeah, exactly, 311 00:16:00,840 --> 00:16:02,880 Speaker 3: so a million wats. There are people trying to figure 312 00:16:02,880 --> 00:16:04,800 Speaker 3: out ways to take out washing machine and make it 313 00:16:04,800 --> 00:16:06,840 Speaker 3: really skiy. So you just stack it up so it 314 00:16:06,920 --> 00:16:09,960 Speaker 3: all fits in. It could work. We'll see what they 315 00:16:09,960 --> 00:16:10,960 Speaker 3: come up with over the next time. 316 00:16:11,640 --> 00:16:13,520 Speaker 1: And you said lasers or is that the same technology? 317 00:16:13,520 --> 00:16:15,640 Speaker 3: Oh, lasers are another thing that people are thinking about. 318 00:16:15,880 --> 00:16:19,480 Speaker 3: This is now on the visible light spectrum. Now that 319 00:16:19,600 --> 00:16:22,640 Speaker 3: laser hits the rock, same thing, burning it melts it. 320 00:16:23,400 --> 00:16:26,600 Speaker 1: That's right. Forget drills. There's a way to shoot your 321 00:16:26,640 --> 00:16:29,360 Speaker 1: way to the center of the Earth. And for anyone 322 00:16:29,400 --> 00:16:32,040 Speaker 1: having flashbacks to the depth Star laser in the movie 323 00:16:32,040 --> 00:16:35,600 Speaker 1: Star Wars, don't worry. These are not that big, just 324 00:16:35,720 --> 00:16:40,040 Speaker 1: enough to cut a small hole ten kilometers into the ground. Now, 325 00:16:40,080 --> 00:16:43,800 Speaker 1: are lasers and microwaves better than drills? I asked doctor 326 00:16:43,840 --> 00:16:48,080 Speaker 1: sure this question, and these methods laser, MicroID that's going 327 00:16:48,160 --> 00:16:51,560 Speaker 1: to be more efficient or better than a drill. 328 00:16:51,840 --> 00:16:55,760 Speaker 3: So it may be faster because your typical rotary drill 329 00:16:55,760 --> 00:16:58,360 Speaker 3: bits if you're looking at easy to drill rock, So 330 00:16:58,560 --> 00:17:02,320 Speaker 3: just a nice easy sandstone, you can drill at hundreds 331 00:17:02,360 --> 00:17:04,840 Speaker 3: of feet per hour, So if you want to drill 332 00:17:04,880 --> 00:17:08,639 Speaker 3: a mile, it'll take maybe a day if you're drilling 333 00:17:08,640 --> 00:17:10,880 Speaker 3: it harder rock. So I just say you're drilling into 334 00:17:11,040 --> 00:17:14,159 Speaker 3: granite or quartz sites, that rock is a lot harder. 335 00:17:14,400 --> 00:17:16,600 Speaker 3: It's the same type of rock that use for your countertop. 336 00:17:16,880 --> 00:17:19,440 Speaker 3: So now if you have a rock like this, erotary 337 00:17:19,520 --> 00:17:22,640 Speaker 3: drill bit could only go at tens of feet per hour, 338 00:17:22,880 --> 00:17:25,760 Speaker 3: so that same mile might take a week or maybe 339 00:17:25,880 --> 00:17:29,119 Speaker 3: I'd say even a month. Sometimes with laser and microwave, 340 00:17:29,400 --> 00:17:31,920 Speaker 3: it doesn't care what the rock is. It just sees matter, 341 00:17:32,119 --> 00:17:34,760 Speaker 3: so it's able to go through any hardness of material 342 00:17:35,400 --> 00:17:37,359 Speaker 3: use it just by blasting it with energy. You just 343 00:17:37,400 --> 00:17:39,680 Speaker 3: maybe crank up the energy intensity a little bit too, 344 00:17:39,880 --> 00:17:41,560 Speaker 3: because if you have more material there. 345 00:17:41,720 --> 00:17:44,800 Speaker 1: Whoah, well, when they build it, they should definitely build 346 00:17:44,800 --> 00:17:47,680 Speaker 1: in some sound effects like pew pew pew. 347 00:17:47,800 --> 00:17:51,560 Speaker 3: Great exactly that or maybe well, I don't know. The 348 00:17:51,920 --> 00:17:53,879 Speaker 3: usually the depth star sud might be a little. 349 00:17:53,640 --> 00:18:00,560 Speaker 1: Bit okay, So to recap, the deepest holes in the 350 00:18:00,560 --> 00:18:03,679 Speaker 1: world have all been dug with drills that make holes 351 00:18:03,720 --> 00:18:06,760 Speaker 1: about nine inches wide, which is about the diameter of 352 00:18:06,800 --> 00:18:09,639 Speaker 1: a soccer ball at the end of a ten kilometer 353 00:18:09,920 --> 00:18:13,280 Speaker 1: or more steel tube or rod, and you typically fill 354 00:18:13,320 --> 00:18:16,800 Speaker 1: that tube with something drilling engineers called mud, which is 355 00:18:16,920 --> 00:18:20,240 Speaker 1: basically water with things like clay or other ceramics added 356 00:18:20,320 --> 00:18:23,600 Speaker 1: to make it heavier to keep the hole from collapsing. Now, 357 00:18:23,640 --> 00:18:26,760 Speaker 1: the question is how deep can you make that hole? 358 00:18:27,160 --> 00:18:29,119 Speaker 1: Can you make it to the center of the earth. 359 00:18:29,520 --> 00:18:31,560 Speaker 1: When we come back, we're going to answer that question. 360 00:18:31,920 --> 00:18:45,720 Speaker 1: So stay with us. You're listening to sign stuff. Welcome back. Okay, 361 00:18:45,760 --> 00:18:47,640 Speaker 1: we're now going to get to the question of whether 362 00:18:47,720 --> 00:18:50,200 Speaker 1: it's possible to dig to the center of the earth. 363 00:18:50,600 --> 00:18:53,040 Speaker 1: We talked about why it's hard to dig really deep 364 00:18:53,040 --> 00:18:56,480 Speaker 1: holes and the technologies humans used to dig them. Now 365 00:18:56,520 --> 00:18:59,400 Speaker 1: the question is what's the deepest hole we could make. 366 00:19:00,320 --> 00:19:02,600 Speaker 1: I asked this question to both of our experts, and 367 00:19:03,119 --> 00:19:07,439 Speaker 1: they disagree. They each gave a different answer. Here's what 368 00:19:07,480 --> 00:19:10,920 Speaker 1: doctor van Ord said. Can you take us on a journey. 369 00:19:11,000 --> 00:19:13,119 Speaker 1: So let's say I start digging from the surface. What 370 00:19:13,200 --> 00:19:14,080 Speaker 1: am I going to be seeing? 371 00:19:14,200 --> 00:19:17,080 Speaker 2: Okay, so the outer part of the earth, which is 372 00:19:17,119 --> 00:19:20,560 Speaker 2: what we call the crust, is relatively thin zero to 373 00:19:20,720 --> 00:19:23,920 Speaker 2: seventy zero to one hundred kilometers deep. But remember that 374 00:19:23,960 --> 00:19:27,200 Speaker 2: the deepest we've ever drilled, which is cola super deep 375 00:19:27,200 --> 00:19:32,040 Speaker 2: hole in Russia, only went about thirteen kilometers deep. So 376 00:19:32,119 --> 00:19:35,600 Speaker 2: you're still only a small ways into the crust. If 377 00:19:35,600 --> 00:19:38,080 Speaker 2: the rest of the crust is one hundred kilometers. 378 00:19:37,600 --> 00:19:39,000 Speaker 1: Right, what is the crust made out of? 379 00:19:39,280 --> 00:19:42,560 Speaker 2: Crust is made out of aluminum and manganese silicates, so 380 00:19:42,640 --> 00:19:45,439 Speaker 2: that's sandstone and limestone, and then deeper down when you 381 00:19:45,440 --> 00:19:48,320 Speaker 2: get the basement rock kind of granite and buzzle, and 382 00:19:48,359 --> 00:19:50,159 Speaker 2: then when you go through the crust you go to 383 00:19:50,200 --> 00:19:50,679 Speaker 2: the mantle. 384 00:19:51,480 --> 00:19:54,280 Speaker 1: All right, here, it's fourteen A side note, I think 385 00:19:54,320 --> 00:19:56,480 Speaker 1: most people know that the inside of the Earth is 386 00:19:56,520 --> 00:19:58,480 Speaker 1: made up of layers, but maybe not a lot of 387 00:19:58,520 --> 00:20:02,119 Speaker 1: people know why it layers. Remember I said earlier that 388 00:20:02,240 --> 00:20:04,560 Speaker 1: after the Earth formed, it was just a big ball 389 00:20:04,600 --> 00:20:07,320 Speaker 1: of lava. Well, when it was in that fluid state, 390 00:20:07,680 --> 00:20:10,600 Speaker 1: all the things in it started to settle. The heaviest 391 00:20:10,600 --> 00:20:13,040 Speaker 1: elements sank to the bottom. In this case, it was 392 00:20:13,119 --> 00:20:16,359 Speaker 1: mostly iron. Then the heavier rocks hung around the middle 393 00:20:16,600 --> 00:20:19,679 Speaker 1: and the lighter rocks floated to the top. I usually 394 00:20:19,680 --> 00:20:22,880 Speaker 1: describe it as a boba drink, or like making sangria, 395 00:20:23,200 --> 00:20:25,880 Speaker 1: where the boba or the fruit sink to the bottom, 396 00:20:26,040 --> 00:20:28,040 Speaker 1: the ice floats to the top, and most of the 397 00:20:28,080 --> 00:20:30,720 Speaker 1: liquid hangs out in the middle. That's why the earth 398 00:20:30,800 --> 00:20:33,160 Speaker 1: is made up of layers, but in this case there's 399 00:20:33,240 --> 00:20:38,040 Speaker 1: circular layers because the earth is round. Okay, back to 400 00:20:38,080 --> 00:20:38,640 Speaker 1: the conversation. 401 00:20:39,600 --> 00:20:42,320 Speaker 2: And then below the crust is the mantle. The mantle 402 00:20:42,359 --> 00:20:44,359 Speaker 2: is about three thousand kilometers. 403 00:20:44,040 --> 00:20:47,400 Speaker 1: So the mantle is also rock, but it's still pretty 404 00:20:47,440 --> 00:20:48,359 Speaker 1: hard and hot. 405 00:20:48,680 --> 00:20:51,439 Speaker 2: Yeah, and the temperatures start to become higher and higher, right, 406 00:20:51,520 --> 00:20:55,040 Speaker 2: it becomes thousands of the grease centigrade and fahrenheit as 407 00:20:55,080 --> 00:20:56,919 Speaker 2: we go towards the core of the earth. 408 00:20:57,600 --> 00:21:00,359 Speaker 1: So after the crust is a mantle. This is kind 409 00:21:00,400 --> 00:21:02,800 Speaker 1: of the meat of the earth, if Earth was like 410 00:21:02,840 --> 00:21:05,919 Speaker 1: a fruit. The mantle is about two thousand, eight hundred 411 00:21:06,000 --> 00:21:09,439 Speaker 1: kilometers thick, and it's also solid rock, but because of 412 00:21:09,480 --> 00:21:13,720 Speaker 1: the temperature and pressure, the rock actually flows. The rocks 413 00:21:13,720 --> 00:21:17,080 Speaker 1: inside the mantle are constantly moving. They heat up when 414 00:21:17,080 --> 00:21:19,240 Speaker 1: they get close to the center of the earth, which 415 00:21:19,280 --> 00:21:22,200 Speaker 1: makes them expand, and so they float up to the crust. 416 00:21:23,280 --> 00:21:26,840 Speaker 1: Then they cool down and sink again. It's kind of 417 00:21:26,840 --> 00:21:29,359 Speaker 1: what happens in a lava lamp or a pot of 418 00:21:29,440 --> 00:21:32,520 Speaker 1: boiling water where you see the water churning up and down. 419 00:21:32,640 --> 00:21:36,040 Speaker 1: And it's that constant movement that pushes the crust around, 420 00:21:36,240 --> 00:21:39,439 Speaker 1: moving all the continents over millions of years. And as 421 00:21:39,440 --> 00:21:43,280 Speaker 1: sucufan Ort said, the mantle gets pretty hot pretty fast. 422 00:21:44,040 --> 00:21:47,640 Speaker 1: At about five hundred kilometers down, the temperature is almost 423 00:21:47,640 --> 00:21:50,959 Speaker 1: two thousand degrees celsius. And at the bottom of the mantle, 424 00:21:51,240 --> 00:21:55,400 Speaker 1: or almost three thousand kilometers deep, the temperature is thirty 425 00:21:55,400 --> 00:21:59,000 Speaker 1: five hundred degrees celsius. That's where you get to the 426 00:21:59,080 --> 00:21:59,919 Speaker 1: Earth's core. 427 00:22:01,040 --> 00:22:04,680 Speaker 2: The outer core is liquid iron and nickel, and then 428 00:22:04,760 --> 00:22:08,600 Speaker 2: the core itself. The scientists are still investigating that. They 429 00:22:08,600 --> 00:22:12,359 Speaker 2: think it's either solid or it's plasma behaving as a solid. 430 00:22:12,560 --> 00:22:15,639 Speaker 2: That is kind of six thousand calvins. So you wouldn't 431 00:22:15,680 --> 00:22:17,680 Speaker 2: be able to drill a borehole through that. In fact, 432 00:22:17,680 --> 00:22:19,399 Speaker 2: if you get to the outer core, right, it's just 433 00:22:19,440 --> 00:22:22,680 Speaker 2: a liquid of iron. Any steel tools that you would 434 00:22:22,800 --> 00:22:26,160 Speaker 2: use would melt going through there. 435 00:22:26,400 --> 00:22:28,880 Speaker 1: Basically, Yeah, if you took a bunch of iron and 436 00:22:28,920 --> 00:22:31,040 Speaker 1: melted it and then you try to dig through a 437 00:22:31,080 --> 00:22:32,760 Speaker 1: pool of liquid iron. 438 00:22:32,760 --> 00:22:36,040 Speaker 2: Yeah, I don't think you can stabilize a borehole at all. 439 00:22:36,600 --> 00:22:38,159 Speaker 1: Well, you know, I've heard that at the center of 440 00:22:38,160 --> 00:22:40,600 Speaker 1: the Earth there are dinosaurs in kin Kong. 441 00:22:40,600 --> 00:22:42,560 Speaker 2: Creatures not from scientists. 442 00:22:44,480 --> 00:22:47,320 Speaker 1: So the outer part of Earth's core is a layer 443 00:22:47,440 --> 00:22:52,240 Speaker 1: of molten iron that's about five thousand degrees celsius. And 444 00:22:52,280 --> 00:22:54,159 Speaker 1: then when you get to the bottom or to the 445 00:22:54,200 --> 00:22:57,080 Speaker 1: center of the Earth, it's a solid ball of iron 446 00:22:57,520 --> 00:23:01,479 Speaker 1: six thousand degrees celsius. Doctor event Or doesn't think we 447 00:23:01,520 --> 00:23:05,480 Speaker 1: could ever even get there. Well, let's maybe put on 448 00:23:05,520 --> 00:23:08,919 Speaker 1: our imagination hads or creative hats, and let's say that 449 00:23:09,160 --> 00:23:11,719 Speaker 1: if for some reason we needed to dig to the 450 00:23:11,720 --> 00:23:14,800 Speaker 1: center of the earth, what would be required? How would 451 00:23:14,800 --> 00:23:18,240 Speaker 1: you do it? And I gave you a trillion dollars? 452 00:23:18,560 --> 00:23:22,480 Speaker 1: Now it wouldn't be enough, all right, ten trillion dollars. 453 00:23:23,240 --> 00:23:27,800 Speaker 1: Now there's no money enough right now because the technology 454 00:23:27,840 --> 00:23:31,280 Speaker 1: doesn't exist to do it. What would be the things 455 00:23:31,280 --> 00:23:31,680 Speaker 1: that fail? 456 00:23:32,160 --> 00:23:35,919 Speaker 2: Well, right now, we require kind of boattholes, right that 457 00:23:35,960 --> 00:23:38,600 Speaker 2: we need to stabilize on our way down. And you 458 00:23:38,760 --> 00:23:40,880 Speaker 2: just run out of the ability to do that as 459 00:23:40,880 --> 00:23:42,719 Speaker 2: you get deeper and deeper. As I said, you need 460 00:23:42,760 --> 00:23:45,880 Speaker 2: to come up with some kind of death Star weapon, right, 461 00:23:46,000 --> 00:23:48,359 Speaker 2: some kind of high powered laser where you could just 462 00:23:48,480 --> 00:23:50,879 Speaker 2: blash your way through the core of the Earth. But 463 00:23:50,880 --> 00:23:52,359 Speaker 2: if you do that, I think you'll blow up the 464 00:23:52,400 --> 00:23:55,360 Speaker 2: Earth in the process as well as the death Star 465 00:23:55,640 --> 00:23:57,520 Speaker 2: is meant to do. 466 00:23:57,880 --> 00:24:01,480 Speaker 1: What's the problem? The rockets too hard or too hot both. 467 00:24:01,840 --> 00:24:03,800 Speaker 2: We have to go through a lot of hard rock 468 00:24:04,000 --> 00:24:06,600 Speaker 2: initially that is a very very high temperature. 469 00:24:06,800 --> 00:24:08,720 Speaker 1: What if I somehow, I mean I gave you a 470 00:24:08,720 --> 00:24:10,520 Speaker 1: lot of money and some we figure out how to 471 00:24:10,520 --> 00:24:13,480 Speaker 1: make things at a diamond, which is the hardest thing 472 00:24:13,640 --> 00:24:16,000 Speaker 1: we know about. Right, What if I made a borehole 473 00:24:16,560 --> 00:24:18,800 Speaker 1: pipe that was made out of diamonds and SOMEO Now 474 00:24:18,800 --> 00:24:21,040 Speaker 1: all my tools and cables were made out of diamonds. 475 00:24:21,200 --> 00:24:24,840 Speaker 2: No, it's a diamond, diamonds decomposed I think at around 476 00:24:24,960 --> 00:24:27,920 Speaker 2: twelve hundred degrees cent grade. I might be wrong there, 477 00:24:27,960 --> 00:24:30,359 Speaker 2: but you can actually burn up a diamond. So the 478 00:24:30,400 --> 00:24:33,679 Speaker 2: diamonds would eventually fail as well. What and you end 479 00:24:33,760 --> 00:24:36,600 Speaker 2: up with just a bunch of CO two. It just 480 00:24:36,640 --> 00:24:38,680 Speaker 2: would revert back to carbon and then you just burn 481 00:24:38,760 --> 00:24:39,240 Speaker 2: the carbon. 482 00:24:39,680 --> 00:24:42,960 Speaker 1: Okay, I checked this, and it's true. Diamonds in the 483 00:24:43,000 --> 00:24:46,680 Speaker 1: presence of air or oxygen burn into CO two at 484 00:24:46,720 --> 00:24:50,000 Speaker 1: around nine hundred degrees celsius, which would only get you 485 00:24:50,080 --> 00:24:54,000 Speaker 1: down to about fifty kilometers or zero point four percent 486 00:24:54,440 --> 00:24:56,800 Speaker 1: of the way to the center of the Earth. In 487 00:24:56,840 --> 00:24:59,640 Speaker 1: other words, when you get down to about fifty kilometers 488 00:24:59,720 --> 00:25:04,200 Speaker 1: now into the earth, your diamond tools would spontaneously burst 489 00:25:04,320 --> 00:25:08,560 Speaker 1: into flames. And even if you stucked all the oxygen out, 490 00:25:08,760 --> 00:25:12,480 Speaker 1: your diamond tools would melt at around fifteen hundred kilometers 491 00:25:12,600 --> 00:25:14,639 Speaker 1: or about a quarter of the way down to the 492 00:25:14,640 --> 00:25:17,520 Speaker 1: center of the earth. Wait, even if I build everything 493 00:25:17,520 --> 00:25:21,280 Speaker 1: out of diamonds, at some point, it would just evaporate. Yeah, 494 00:25:21,480 --> 00:25:23,960 Speaker 1: so we wouldn't get very far even into the mantle. 495 00:25:24,240 --> 00:25:27,520 Speaker 2: No, I personally think it'll be a very long time 496 00:25:27,600 --> 00:25:30,240 Speaker 2: before we can get out of the crust and into 497 00:25:30,280 --> 00:25:30,760 Speaker 2: the mantle. 498 00:25:32,480 --> 00:25:35,119 Speaker 1: All right, So our dream of going to the center 499 00:25:35,160 --> 00:25:38,200 Speaker 1: of the Earth just went up and smoke right along 500 00:25:38,240 --> 00:25:43,320 Speaker 1: with our cool diamond drills, or did they. I decided 501 00:25:43,359 --> 00:25:46,640 Speaker 1: to ask doctor Share the same question, and he came 502 00:25:46,720 --> 00:25:49,480 Speaker 1: up with a possible way we might be able to 503 00:25:49,560 --> 00:25:52,560 Speaker 1: get down to the Earth's core. And the answer is 504 00:25:52,600 --> 00:25:55,240 Speaker 1: to use the liquid that you fill your hole with, 505 00:25:55,640 --> 00:25:59,440 Speaker 1: the one keeping the hole from collapsing as a coolant. 506 00:26:00,160 --> 00:26:01,960 Speaker 1: This is what they do. When you're drilling and you 507 00:26:02,040 --> 00:26:04,600 Speaker 1: hit a pocket of lava or magma. 508 00:26:05,600 --> 00:26:08,200 Speaker 3: The cool thing is that drill bit can drill into 509 00:26:08,240 --> 00:26:11,639 Speaker 3: that magma. The reason why is the water so that 510 00:26:11,720 --> 00:26:14,720 Speaker 3: fluid that you're using is cooling the rock. So that 511 00:26:15,000 --> 00:26:18,480 Speaker 3: layer of magma now it sees that fluid first and 512 00:26:18,520 --> 00:26:22,399 Speaker 3: it solidifies. In Hawaii and in Iceland, they have drilled 513 00:26:22,400 --> 00:26:25,680 Speaker 3: through magma dikes. Sometimes it's been on purpose, sometimes it's 514 00:26:25,680 --> 00:26:28,240 Speaker 3: been not and they were able to drill through it. 515 00:26:28,240 --> 00:26:31,240 Speaker 3: It cools off because the water is absorbed all that heat. 516 00:26:31,400 --> 00:26:33,640 Speaker 3: So you have this little tiny layer now around your 517 00:26:33,640 --> 00:26:38,000 Speaker 3: hole that's solid rock and then it's magma. 518 00:26:37,160 --> 00:26:39,240 Speaker 1: And it doesn't remelt. 519 00:26:39,160 --> 00:26:41,080 Speaker 3: As long as you're flowing the water. So as long 520 00:26:41,080 --> 00:26:43,760 Speaker 3: as you're still pumping and pumping cool fluid, now it 521 00:26:43,840 --> 00:26:44,800 Speaker 3: stays water. 522 00:26:45,840 --> 00:26:48,560 Speaker 1: To you're building a tunnel through lava. 523 00:26:49,040 --> 00:26:52,120 Speaker 3: H as long as you continue flowing fluid and cooling, 524 00:26:52,440 --> 00:26:53,600 Speaker 3: that whole stays stable. 525 00:26:53,840 --> 00:26:53,959 Speaker 2: Right. 526 00:26:54,000 --> 00:26:56,760 Speaker 3: But now you can keep going even deeper than that. 527 00:26:56,880 --> 00:26:58,920 Speaker 3: It's imagine we keep cool they canna say we're using 528 00:26:58,920 --> 00:27:01,960 Speaker 3: liquid nitrogen or something. We can now technically keep making 529 00:27:02,000 --> 00:27:02,400 Speaker 3: this whole. 530 00:27:02,680 --> 00:27:04,879 Speaker 1: This is the mantle, right, Yes, for an hour, and 531 00:27:04,920 --> 00:27:06,840 Speaker 1: they're layer beneath the crust, and. 532 00:27:06,800 --> 00:27:09,359 Speaker 3: The temperatures are going to be increasing through thousands of 533 00:27:09,440 --> 00:27:10,159 Speaker 3: degrees fahrenheit. 534 00:27:10,400 --> 00:27:13,720 Speaker 1: Now is that survivable? Because now you're talking about thousands 535 00:27:13,760 --> 00:27:17,720 Speaker 1: of degrees and you know the surfaces of the sun 536 00:27:17,760 --> 00:27:22,119 Speaker 1: is six thousand degrees fahrenheit. Is your drill bit still intact? 537 00:27:22,440 --> 00:27:27,080 Speaker 3: The drill bit itself would have melted hours ago. Part 538 00:27:27,080 --> 00:27:29,280 Speaker 3: of the reason why we're still able to keep drilling 539 00:27:29,400 --> 00:27:31,560 Speaker 3: is because we have this cool layer of rock that's 540 00:27:31,560 --> 00:27:34,880 Speaker 3: solidified around us. So if we somehow found a way 541 00:27:34,960 --> 00:27:39,280 Speaker 3: to continue pumping some form of cool fluid, maybe liquid nitrogen, 542 00:27:39,359 --> 00:27:42,639 Speaker 3: Maybe we find a fluid where it reacts and it 543 00:27:42,720 --> 00:27:45,800 Speaker 3: absorbs heat, so you can pump down let's say two materials. 544 00:27:45,880 --> 00:27:49,080 Speaker 3: They combine and become extremely cold. So as long as 545 00:27:49,119 --> 00:27:52,080 Speaker 3: the rock is solid, the bit will be fine because 546 00:27:52,080 --> 00:27:54,640 Speaker 3: the bit melts right about the same temperature as the rock. 547 00:27:55,880 --> 00:27:58,840 Speaker 1: Right, So if we can keep our drill cool, maybe 548 00:27:58,960 --> 00:28:03,840 Speaker 1: using some kind of system, you could technically keep digging. Now, 549 00:28:03,880 --> 00:28:08,480 Speaker 1: this is an extremely difficult problem, but maybe technically possible. 550 00:28:09,240 --> 00:28:12,240 Speaker 1: We're kind of using our imagination here, but that would 551 00:28:12,280 --> 00:28:13,600 Speaker 1: get us to the core. 552 00:28:14,600 --> 00:28:18,119 Speaker 3: Eventually, after about two thousand miles, you've now hit the 553 00:28:18,160 --> 00:28:22,080 Speaker 3: outer core. The outer core now is still liquid, it 554 00:28:22,119 --> 00:28:25,240 Speaker 3: is now extremely hot, so four thousand and five thousand 555 00:28:25,320 --> 00:28:28,080 Speaker 3: degrees fahrenheit. And then at the very center, now you 556 00:28:28,119 --> 00:28:31,119 Speaker 3: have a solid inner core. That solid inner core is 557 00:28:31,119 --> 00:28:34,959 Speaker 3: not mostly metal, and it's spinning, and it's spinning at 558 00:28:35,000 --> 00:28:37,320 Speaker 3: a different speed than the surface of the Earth. So 559 00:28:37,600 --> 00:28:40,600 Speaker 3: the reason why we as a planet have a magnetic 560 00:28:40,640 --> 00:28:43,280 Speaker 3: field is the center of the Earth is spinning. The 561 00:28:43,360 --> 00:28:46,240 Speaker 3: outside of the Earth is stationary, so it's a big dynamo. 562 00:28:46,520 --> 00:28:50,040 Speaker 3: So that is what is generating this magnetic field that 563 00:28:50,120 --> 00:28:52,160 Speaker 3: protects the planet from all this solar radiation. 564 00:28:52,480 --> 00:28:55,480 Speaker 1: It's a spinning magnet in the center of the Earth exactly. 565 00:28:55,520 --> 00:28:59,440 Speaker 3: Which is why Mars does not have a magnetic field anymore, 566 00:28:59,520 --> 00:29:03,680 Speaker 3: is because their core became solid and it stopped rotating 567 00:29:03,840 --> 00:29:06,080 Speaker 3: at some point several billion years ago. 568 00:29:06,280 --> 00:29:12,000 Speaker 1: Whoa, but wait, but trying to dig through molten metal iron. 569 00:29:12,480 --> 00:29:15,800 Speaker 3: That's going to become even harder and again it's moving, 570 00:29:16,000 --> 00:29:18,160 Speaker 3: which is the bigger problem. So we have this hole 571 00:29:18,200 --> 00:29:20,920 Speaker 3: that's cooled around us. We're still somehow cooling it. I 572 00:29:20,960 --> 00:29:24,480 Speaker 3: don't know how. And we've now hit this moving metal ball. 573 00:29:25,280 --> 00:29:27,920 Speaker 3: Where we touch it, it's going to move away. And 574 00:29:28,000 --> 00:29:30,320 Speaker 3: now if we start making a hole, it's going to 575 00:29:30,360 --> 00:29:33,640 Speaker 3: start dragging our hole with it because it's moving in 576 00:29:33,720 --> 00:29:38,760 Speaker 3: relation to us. So how would we continue drilling at 577 00:29:38,800 --> 00:29:39,719 Speaker 3: that point? I don't know. 578 00:29:40,440 --> 00:29:42,240 Speaker 1: Well what I have an idea? What if we drill 579 00:29:42,280 --> 00:29:43,160 Speaker 1: from the north pole? 580 00:29:44,520 --> 00:29:47,160 Speaker 3: That could actually work. But if you find the pole 581 00:29:47,240 --> 00:29:49,480 Speaker 3: of that inner core, then yes, that would work. 582 00:29:49,880 --> 00:29:53,520 Speaker 1: Oh, you'd have to hit it just right in the 583 00:29:53,560 --> 00:29:55,400 Speaker 1: spin axis in the inner. 584 00:29:55,160 --> 00:29:57,760 Speaker 3: Core exactly, so it has a rock tube transition to 585 00:29:57,840 --> 00:30:02,840 Speaker 3: a metal tube. Now you're in solid metal, but around 586 00:30:02,880 --> 00:30:06,600 Speaker 3: you the core is thousands of degrees fahrenheit. So you 587 00:30:06,680 --> 00:30:09,440 Speaker 3: now need to have enough cooling that the inside of 588 00:30:09,440 --> 00:30:12,320 Speaker 3: your hole is one hundred degrees or couple hudgrees fahit. 589 00:30:12,440 --> 00:30:14,320 Speaker 3: So you may have to get creative and call NASA 590 00:30:14,400 --> 00:30:16,520 Speaker 3: because NASA has some really cool insulators. 591 00:30:16,840 --> 00:30:20,120 Speaker 1: Yeah, hold on, let me call NASA right now. Actually 592 00:30:20,160 --> 00:30:21,280 Speaker 1: we do have it all night phone. 593 00:30:23,800 --> 00:30:24,160 Speaker 3: Okay. 594 00:30:24,240 --> 00:30:26,640 Speaker 1: So to recap, if you drill down from the north 595 00:30:26,720 --> 00:30:29,280 Speaker 1: or south poles, and if you can figure out a 596 00:30:29,320 --> 00:30:32,080 Speaker 1: way to super cool your whole as you dig down 597 00:30:32,160 --> 00:30:36,040 Speaker 1: through six thousand degrees celsius molten and solid iron, you 598 00:30:36,120 --> 00:30:39,400 Speaker 1: could technically drill down to the center of the Earth. 599 00:30:40,200 --> 00:30:42,640 Speaker 1: I feel like maybe we delved a little bit into 600 00:30:42,680 --> 00:30:46,640 Speaker 1: science fiction, a little bit or a lot of just 601 00:30:46,720 --> 00:30:50,760 Speaker 1: a little bit, But in your opinion, it's possible as 602 00:30:50,800 --> 00:30:52,240 Speaker 1: long as we have the right engineering. 603 00:30:52,360 --> 00:30:55,120 Speaker 3: If we need to and we put our brains to it, 604 00:30:55,200 --> 00:30:59,200 Speaker 3: we probably could come up with aspects of a solution 605 00:30:59,280 --> 00:31:02,000 Speaker 3: that could work. Will we be able to cool against 606 00:31:02,040 --> 00:31:06,440 Speaker 3: six thousand degrees fahrenheit two thousand miles into the Earth's core? 607 00:31:06,840 --> 00:31:10,640 Speaker 3: Probably not, but should we find a way so. For 608 00:31:10,880 --> 00:31:13,560 Speaker 3: the geothermal industry today, what they're trying to do is 609 00:31:13,560 --> 00:31:15,880 Speaker 3: they're trying to find a way to drill down to 610 00:31:16,600 --> 00:31:18,320 Speaker 3: rock that is six hundred degrees fahrenheit. 611 00:31:18,960 --> 00:31:21,480 Speaker 1: Okay, this brings us to one of the main reasons 612 00:31:21,520 --> 00:31:23,560 Speaker 1: why you would want to dig a deep hole in 613 00:31:23,600 --> 00:31:29,080 Speaker 1: the first place, geothermal energy, that is, using the energy 614 00:31:29,120 --> 00:31:32,480 Speaker 1: of the Earth as energy instead of oil or carbon. 615 00:31:32,720 --> 00:31:36,880 Speaker 1: Because this energy is free and it's clean, and you 616 00:31:36,880 --> 00:31:38,719 Speaker 1: don't have to go down that deep to get it. 617 00:31:39,200 --> 00:31:42,240 Speaker 1: Scientists think if we can get technology towards easy to 618 00:31:42,320 --> 00:31:45,480 Speaker 1: drill down to about twelve kilometers, which is about the 619 00:31:45,520 --> 00:31:49,560 Speaker 1: deepest we've ever dug. Then you could have geothermal wells everywhere. 620 00:31:49,840 --> 00:31:51,640 Speaker 1: Here's how doctor Shore describes it. 621 00:31:52,560 --> 00:31:56,040 Speaker 3: I think someone's done the calculations, and there's enough heat 622 00:31:56,160 --> 00:31:58,840 Speaker 3: energy in the Earth in order to provide enough energy 623 00:31:58,840 --> 00:32:02,080 Speaker 3: for humanity for a hundred million years. So there is 624 00:32:02,120 --> 00:32:05,280 Speaker 3: a huge amount, but it's not unlimited. So it's now, 625 00:32:05,320 --> 00:32:09,040 Speaker 3: how do you sustainably pull out heat and make sure 626 00:32:09,040 --> 00:32:13,240 Speaker 3: you're not changing the geology significantly from that heat being removed. 627 00:32:14,040 --> 00:32:16,080 Speaker 3: I see, So there has to be a little bit 628 00:32:16,080 --> 00:32:17,960 Speaker 3: of thought put into it. But one hundred million of 629 00:32:18,000 --> 00:32:19,720 Speaker 3: years worth of energy sounds pretty good. 630 00:32:22,800 --> 00:32:25,640 Speaker 1: And that sounds good to me too. So when you 631 00:32:25,640 --> 00:32:29,000 Speaker 1: hear politicians say drill, baby, drill, just make sure they 632 00:32:29,040 --> 00:32:33,160 Speaker 1: mean for geothermal energy. All right, I think we answered 633 00:32:33,200 --> 00:32:35,760 Speaker 1: today's question. What happens if you dig a hole to 634 00:32:35,800 --> 00:32:38,360 Speaker 1: the center of the earth. It might be possible to 635 00:32:38,400 --> 00:32:41,320 Speaker 1: do it, but you might not need to might not 636 00:32:41,440 --> 00:32:44,360 Speaker 1: be that deep. A solution to all of our problems 637 00:32:44,520 --> 00:32:48,959 Speaker 1: could be right beneath our feet. That is the whole truth. 638 00:32:49,480 --> 00:32:55,120 Speaker 1: Thanks for joining us. See you next time you've been 639 00:32:55,160 --> 00:32:59,040 Speaker 1: listening to science stuff. The production of iHeartRadio written and 640 00:32:59,080 --> 00:33:02,520 Speaker 1: produced by me or Hey Chham, edited by Rose Seguda, 641 00:33:02,960 --> 00:33:06,800 Speaker 1: executive producer Jerry Rowland, and audio engineer and mixer Ksey Pegram. 642 00:33:07,280 --> 00:33:09,440 Speaker 1: And you can follow me on social media. Just search 643 00:33:09,480 --> 00:33:12,600 Speaker 1: for PhD Comics and the name of your favorite platform. 644 00:33:12,800 --> 00:33:15,720 Speaker 1: Be sure to subscribe to sign stuff on the iHeartRadio app, 645 00:33:15,800 --> 00:33:19,000 Speaker 1: Apple Podcasts or wherever you get your podcasts, and please 646 00:33:19,200 --> 00:33:22,720 Speaker 1: tell your friends We'll be back next Wednesday with another episode.