WEBVTT 1 00:00:24.520 --> 00:00:26.220 Thank you all for coming tonight. 2 00:00:26.220 --> 00:00:27.222 Is this still working? 3 00:00:27.222 --> 00:00:29.620 Okay. It's great to be back. 4 00:00:29.620 --> 00:00:32.020 This is my third time doing Volcano Awareness Month talk. 5 00:00:32.020 --> 00:00:34.820 And I really enjoy engaging with you guys, 6 00:00:34.820 --> 00:00:37.160 so I hope you enjoy this talk. 7 00:00:37.160 --> 00:00:38.820 It's a little different than past years 8 00:00:38.820 --> 00:00:40.580 just because, as the title says, 9 00:00:40.580 --> 00:00:43.500 this year was quiet, but insightful. 10 00:00:43.500 --> 00:00:46.710 So we're going to have a very quick review 11 00:00:46.710 --> 00:00:50.750 of where we are and what Kilauea has done in the past, 12 00:00:50.750 --> 00:00:53.370 and then we'll talk about some things that my colleagues 13 00:00:53.370 --> 00:00:55.590 and I have all been working on together. 14 00:00:55.590 --> 00:00:58.060 There are slides from multiple other people's presentations 15 00:00:58.060 --> 00:00:59.933 in here that I've put all together. 16 00:01:00.920 --> 00:01:02.750 While my name is on this, it's certainly everybody 17 00:01:02.750 --> 00:01:05.263 at HVO who's contributed to what's in this talk. 18 00:01:06.460 --> 00:01:09.063 Okay, so we are here on the Big Island of Hawaii. 19 00:01:10.140 --> 00:01:12.130 We are up here at the national park. 20 00:01:12.130 --> 00:01:14.260 Our island is made up of five volcanoes. 21 00:01:14.260 --> 00:01:16.730 For those of you who are visiting and may not know, 22 00:01:16.730 --> 00:01:18.660 this is Kohala, up top, 23 00:01:18.660 --> 00:01:21.350 Mauna Kea, with the telescopes, Hualalai, 24 00:01:21.350 --> 00:01:24.190 Mauna Loa, which is our largest volcano on the planet, 25 00:01:24.190 --> 00:01:26.090 and Kilauea, where we are. 26 00:01:26.090 --> 00:01:29.230 We also have little Lo'ihi down here, a submarine volcano. 27 00:01:29.230 --> 00:01:31.330 And it's gonna stay underwater for quite some time, 28 00:01:31.330 --> 00:01:34.000 so don't worry about seeing that one. 29 00:01:34.000 --> 00:01:36.020 These are all basaltic shield volcanoes, 30 00:01:36.020 --> 00:01:39.230 which means that they are not your typical conical cone 31 00:01:39.230 --> 00:01:40.840 that most people think of as a volcano. 32 00:01:40.840 --> 00:01:42.880 These are broad shield volcanoes 33 00:01:42.880 --> 00:01:45.110 and they're classic in their own right. 34 00:01:45.110 --> 00:01:47.800 They typically have rift zones. 35 00:01:47.800 --> 00:01:49.910 In our case, they have two rift zones 36 00:01:51.330 --> 00:01:53.010 that come off of a summit caldera. 37 00:01:53.010 --> 00:01:54.990 We have an East Rift Zone that stretches 38 00:01:54.990 --> 00:01:56.162 all the way out here, 39 00:01:56.162 --> 00:01:57.930 and this is what we'll be talking about today. 40 00:01:57.930 --> 00:02:01.003 And we have a Southwest Rift Zone that comes down here. 41 00:02:02.150 --> 00:02:05.360 Under Kilauea, we have at least two magma chambers, 42 00:02:05.360 --> 00:02:07.260 the Halema'uma'u shallow source, 43 00:02:07.260 --> 00:02:10.040 and the south caldera deeper source. 44 00:02:10.040 --> 00:02:11.980 Along the rift zones, this is gonna come into play 45 00:02:11.980 --> 00:02:16.040 in our talk, there are these little stored areas 46 00:02:16.040 --> 00:02:18.370 of magma throughout the whole rift zone. 47 00:02:18.370 --> 00:02:21.040 We'll dive into that a little later. 48 00:02:21.040 --> 00:02:24.081 There's also two major fault systems on our volcano here, 49 00:02:24.081 --> 00:02:27.390 the Koa'e fault system, which links the Upper East Rift Zone 50 00:02:27.390 --> 00:02:29.820 to the seismic Southwest Rift Zone, 51 00:02:29.820 --> 00:02:33.830 and the Hilina fault zone, which basically is part 52 00:02:33.830 --> 00:02:35.060 of the edge of the south flank 53 00:02:35.060 --> 00:02:37.913 that moves on our volcano here. 54 00:02:39.890 --> 00:02:42.467 This is a very abridged eruption history of Kilauea, 55 00:02:42.467 --> 00:02:44.370 and for those of you who are diehard fans 56 00:02:44.370 --> 00:02:45.910 of Volcano Awareness Month, 57 00:02:45.910 --> 00:02:48.230 it's going to be just as odd for you as it is for me 58 00:02:48.230 --> 00:02:50.238 to summarize Pu'u 'O'o in one slide. 59 00:02:50.238 --> 00:02:52.759 (all laughing) 60 00:02:52.759 --> 00:02:54.920 But we're gonna do it. 61 00:02:54.920 --> 00:02:56.670 A brief history of what Kilauea has done, 62 00:02:56.670 --> 00:02:59.200 kind of setting the scene a little more 63 00:02:59.200 --> 00:03:01.650 for what happened in 2018. 64 00:03:01.650 --> 00:03:02.690 In the past 70 years, 65 00:03:02.690 --> 00:03:04.930 we started with a 1955 eruption, 66 00:03:04.930 --> 00:03:08.350 labeled here, these two gray spots. 67 00:03:08.350 --> 00:03:11.660 That was followed in 1959 by the Kilauea Iki eruption 68 00:03:11.660 --> 00:03:13.710 up here at the summit in December. 69 00:03:13.710 --> 00:03:16.180 Then the next month, in January 1960, 70 00:03:16.180 --> 00:03:18.050 the Kapoho eruption happened down here 71 00:03:18.050 --> 00:03:19.450 on the Lower East Rift Zone. 72 00:03:21.020 --> 00:03:22.780 LERZ stands for Lower East Rift Zone 73 00:03:22.780 --> 00:03:25.253 and this is Upper East Rift Zone here. 74 00:03:26.250 --> 00:03:28.360 Through the '60s there were multiple fissures, 75 00:03:28.360 --> 00:03:29.550 roughly one a decade. 76 00:03:29.550 --> 00:03:32.830 Not quite, some years had two and some years had none, 77 00:03:32.830 --> 00:03:34.790 but roughly one a decade, 78 00:03:34.790 --> 00:03:36.560 fissure eruptions on the Upper East Rift Zone 79 00:03:36.560 --> 00:03:38.300 towards Mauna Ulu. 80 00:03:38.300 --> 00:03:40.990 Then in '69, Mauna Ulu started erupting 81 00:03:40.990 --> 00:03:44.910 with some lava fountaining through the rest of that year. 82 00:03:44.910 --> 00:03:47.900 It lasted another four and 1/2 years, till 1974, 83 00:03:47.900 --> 00:03:50.093 all effusive lava flows. 84 00:03:51.030 --> 00:03:52.850 There was some little fountaining here and there, 85 00:03:52.850 --> 00:03:55.163 but no major episodes of that. 86 00:03:56.560 --> 00:03:58.480 There were then some fissure eruptions 87 00:03:58.480 --> 00:03:59.860 in the middle rift zone, here, 88 00:03:59.860 --> 00:04:03.790 and the upper rift zone between 1974 and 1983. 89 00:04:03.790 --> 00:04:06.370 But then, in 1983, we started three years 90 00:04:06.370 --> 00:04:09.650 of 48 different lava fountaining episodes 91 00:04:09.650 --> 00:04:12.360 that became the Pu'u 'O'o eruption. 92 00:04:12.360 --> 00:04:16.190 There was another 32 years, beyond that, of lava effusion. 93 00:04:16.190 --> 00:04:19.583 And that made for a 35-year-long historic eruption. 94 00:04:20.570 --> 00:04:24.450 That was joined at the summit by a 10 year long lava lake 95 00:04:24.450 --> 00:04:26.560 that started in 2008. 96 00:04:26.560 --> 00:04:30.783 But as you can guess, 2018 stopped both of 'em. 97 00:04:32.010 --> 00:04:34.023 So those eruptions have ended. 98 00:04:35.070 --> 00:04:37.070 2018 was historic in its own right, 99 00:04:37.070 --> 00:04:40.053 and we're gonna get into that tonight. 100 00:04:41.890 --> 00:04:45.280 The first day leading up to the eruption, 101 00:04:45.280 --> 00:04:48.893 the first day of precursors, was April 30th, 2018. 102 00:04:50.213 --> 00:04:52.750 Pu'u 'O'o, around 2:15 p.m., 103 00:04:52.750 --> 00:04:57.380 had this massive swelling, or inflation, 104 00:04:57.380 --> 00:04:59.400 and then it collapsed on itself. 105 00:04:59.400 --> 00:05:04.400 This is the cone and it made this typical pink ash plume 106 00:05:04.470 --> 00:05:08.450 for many days that week and several weeks after. 107 00:05:08.450 --> 00:05:11.680 That inflation that happened for about 15 minutes, 108 00:05:11.680 --> 00:05:14.280 cracked the west side of the cone. 109 00:05:14.280 --> 00:05:15.550 It was pretty rainy that day, 110 00:05:15.550 --> 00:05:17.280 so we couldn't see anything on our cameras. 111 00:05:17.280 --> 00:05:19.810 The thermal camera caught a little bit. 112 00:05:19.810 --> 00:05:21.960 But we ended up taking a helicopter out the next day 113 00:05:21.960 --> 00:05:24.670 to see what had happened. 114 00:05:24.670 --> 00:05:27.610 This was a huge signal that had never been seen 115 00:05:27.610 --> 00:05:29.630 to that magnitude here before. 116 00:05:29.630 --> 00:05:31.693 So here's a video from the helicopter. 117 00:05:33.620 --> 00:05:35.990 This used to be filled with lava. 118 00:05:35.990 --> 00:05:37.790 You couldn't see down here. 119 00:05:37.790 --> 00:05:40.240 And when we took this helicopter flight, 120 00:05:40.240 --> 00:05:41.750 we couldn't see the bottom of this hole. 121 00:05:41.750 --> 00:05:44.676 It was at least 500 or 600 meters deep. 122 00:05:44.676 --> 00:05:46.430 There's some little dust that sloughs off 123 00:05:46.430 --> 00:05:47.410 and it just keeps going. 124 00:05:47.410 --> 00:05:49.760 You don't even see it rebound when it hits the bottom. 125 00:05:49.760 --> 00:05:51.580 It was very deep. 126 00:05:51.580 --> 00:05:54.388 It has since filled in with talus. 127 00:05:54.388 --> 00:05:57.890 But that was our first clue, when this collapsed, 128 00:05:57.890 --> 00:05:58.930 that something was happening. 129 00:05:58.930 --> 00:06:02.770 Then seeing how deep and how big this scar was 130 00:06:02.770 --> 00:06:05.883 inside the crater was really eye-opening. 131 00:06:07.662 --> 00:06:10.300 I'm going to talk about this plot first. 132 00:06:10.300 --> 00:06:13.300 This is the rest of the afternoon of April 30th, 133 00:06:13.300 --> 00:06:14.550 after about 2:30 p.m. 134 00:06:14.550 --> 00:06:17.500 There was earthquakes that started migrating down rift. 135 00:06:17.500 --> 00:06:20.560 And typically, a lot of our activity for the past 35 years 136 00:06:20.560 --> 00:06:22.360 had been in this middle rift zone, at Pu'u 'O'o, 137 00:06:22.360 --> 00:06:25.790 or somewhere in the upper East Rift Zone connector. 138 00:06:25.790 --> 00:06:29.020 But on this day, whatever happened at Pu'u 'O'o, 139 00:06:29.020 --> 00:06:30.740 whatever failed underneath it, 140 00:06:30.740 --> 00:06:32.560 allowed magma to move forward, 141 00:06:32.560 --> 00:06:35.183 down into the lower rift, which is down here. 142 00:06:36.450 --> 00:06:41.450 On May 1st, we see that earthquake front 143 00:06:41.830 --> 00:06:44.160 migrating to the east. 144 00:06:44.160 --> 00:06:48.860 Then, on May 2nd, it stops just short of our station WAPM, 145 00:06:49.920 --> 00:06:52.593 right under the subdivision of Leilani Estates. 146 00:06:54.730 --> 00:06:56.960 To give you a sense of what this image is, 147 00:06:56.960 --> 00:06:59.490 it's derived from what we call InSAR. 148 00:06:59.490 --> 00:07:02.290 It's a satellite that passes over and measures, 149 00:07:02.290 --> 00:07:05.220 it can measure very fine movements of the ground. 150 00:07:05.220 --> 00:07:07.560 Typically, you see it as a colorful rainbow image, 151 00:07:07.560 --> 00:07:09.170 but this has been processed such 152 00:07:09.170 --> 00:07:13.660 that you see subsidence in blue and inflation in red. 153 00:07:13.660 --> 00:07:14.830 These are in millimeters, 154 00:07:14.830 --> 00:07:19.060 so these are not huge distances 155 00:07:19.060 --> 00:07:21.380 even though they look very dark blue. 156 00:07:21.380 --> 00:07:23.660 But it gives you a sense that during this three 157 00:07:23.660 --> 00:07:26.790 or four day period, the entire middle rift zone 158 00:07:26.790 --> 00:07:30.070 and part of the upper rift zone was losing material 159 00:07:30.070 --> 00:07:32.170 in the subsurface to the lower rift zone, 160 00:07:32.170 --> 00:07:33.823 which was becoming engorged. 161 00:07:34.830 --> 00:07:37.270 The other thing that started happening on May 2nd 162 00:07:37.270 --> 00:07:41.410 was that surface streets in Leilani Estates began to crack. 163 00:07:41.410 --> 00:07:42.960 And at first it was one crack. 164 00:07:42.960 --> 00:07:45.560 And then it was two cracks and then it was five cracks, 165 00:07:45.560 --> 00:07:47.850 and then it was 10, and we realized 166 00:07:48.840 --> 00:07:50.733 this is gonna happen fast. 167 00:07:51.880 --> 00:07:54.350 And again, the ground is swelling up 168 00:07:54.350 --> 00:07:57.363 as material is moving under Leilani Estates. 169 00:07:58.300 --> 00:08:01.540 The next day, on May 3rd, we have some more earthquakes 170 00:08:01.540 --> 00:08:02.533 in the same area. 171 00:08:03.700 --> 00:08:08.220 And fissure 1 opens that evening around 4:30 p.m. 172 00:08:08.220 --> 00:08:10.710 It crossed Mohala Street. 173 00:08:10.710 --> 00:08:12.110 This is what it looked like. 174 00:08:15.540 --> 00:08:18.300 You can see it's already starting to make a lava pad, 175 00:08:18.300 --> 00:08:19.930 but that pad's not going very far, 176 00:08:19.930 --> 00:08:21.990 it's only going a couple of feet. 177 00:08:21.990 --> 00:08:24.983 It's actually pretty thick, maybe two or three feet tall. 178 00:08:27.244 --> 00:08:28.700 This is what you would call a classic fissure. 179 00:08:31.090 --> 00:08:35.190 It's a line of, a crack, that erupts magma. 180 00:08:35.190 --> 00:08:38.530 There are multiple sources of gas 181 00:08:38.530 --> 00:08:41.203 pushing the magma out of this crack. 182 00:08:53.556 --> 00:08:56.556 (audience mumbling) 183 00:08:57.530 --> 00:08:58.770 It's pretty sluggish. 184 00:08:58.770 --> 00:09:00.970 It's not what we typically think of 185 00:09:01.940 --> 00:09:04.860 from the pahoehoe from Pu'u 'O'o. 186 00:09:04.860 --> 00:09:06.460 This stuff isn't going very far, 187 00:09:07.530 --> 00:09:09.410 but it's also in a neighborhood, 188 00:09:09.410 --> 00:09:11.973 so that's a good thing it's not going very far. 189 00:09:13.500 --> 00:09:16.470 The next morning, literally at 1:00 a.m. the next morning, 190 00:09:16.470 --> 00:09:18.090 fissure 2 opened. 191 00:09:18.090 --> 00:09:20.840 The next few fissures, all the way to fissure 6, 192 00:09:20.840 --> 00:09:23.510 opened sequentially down rift, 193 00:09:23.510 --> 00:09:25.150 right to about where the earthquakes 194 00:09:25.150 --> 00:09:27.463 had stopped progressing forward. 195 00:09:29.480 --> 00:09:31.040 In the middle of all of that, on May 4th, 196 00:09:31.040 --> 00:09:33.750 we had a magnitude 6.9 earthquake 197 00:09:33.750 --> 00:09:36.130 that was felt throughout the state. 198 00:09:36.130 --> 00:09:39.123 While it shook a lot of us, and especially those in Puna, 199 00:09:41.050 --> 00:09:42.930 it didn't seem to affect those six fissures 200 00:09:42.930 --> 00:09:44.710 that were opening up, or those five fissures 201 00:09:44.710 --> 00:09:46.210 that were opening up that day. 202 00:09:47.070 --> 00:09:50.420 They just carried on with their sluggish spattering 203 00:09:51.640 --> 00:09:53.223 as if nothing was wrong. 204 00:09:55.180 --> 00:09:57.850 During this earthquake, the entire south flank 205 00:09:57.850 --> 00:09:58.920 of Kilauea moved. 206 00:09:58.920 --> 00:10:02.163 This is another one of those InSAR derived diagrams, 207 00:10:03.910 --> 00:10:06.390 150 millimeters is 15 centimeters, 208 00:10:06.390 --> 00:10:09.650 so that's everything from this line and down 209 00:10:09.650 --> 00:10:11.823 moved at least that much, if not more. 210 00:10:15.900 --> 00:10:19.030 On May 6th, after fissure 6 was done erupting over here, 211 00:10:19.030 --> 00:10:21.420 fissure 7 opened up the next morning 212 00:10:21.420 --> 00:10:22.900 right next to fissure 2. 213 00:10:22.900 --> 00:10:26.160 And then the vents started opening up back up rift 214 00:10:26.160 --> 00:10:27.060 with the exception of 12, 215 00:10:27.060 --> 00:10:29.890 that jumped the line and went back down rift. 216 00:10:29.890 --> 00:10:32.583 But, in general, the trend was an up rift migration. 217 00:10:35.870 --> 00:10:38.650 Here's a video of fissure 11. 218 00:10:38.650 --> 00:10:40.360 I turned the sound off in this one because all you hear 219 00:10:40.360 --> 00:10:41.760 is a very loud helicopter. 220 00:10:41.760 --> 00:10:43.840 You can't hear the fissure at all. 221 00:10:43.840 --> 00:10:45.960 But again, it's very sluggish, 222 00:10:45.960 --> 00:10:49.490 perhaps a little more vigorous spattering. 223 00:10:49.490 --> 00:10:51.800 You can see that there's multiple spots 224 00:10:51.800 --> 00:10:53.570 but they're all kind of red together 225 00:10:53.570 --> 00:10:55.860 instead of individual red spots. 226 00:10:55.860 --> 00:10:58.530 But it's lava that's not going very far. 227 00:10:58.530 --> 00:11:00.260 It's very sticky. 228 00:11:00.260 --> 00:11:01.473 It's very viscous. 229 00:11:04.700 --> 00:11:07.700 There were two days of pause, May 10th and May 11th, 230 00:11:07.700 --> 00:11:11.107 where we thought, "Hmm, is that it? 231 00:11:11.107 --> 00:11:13.877 "Are we done, or is there more coming?" 232 00:11:15.390 --> 00:11:17.050 We assumed there was more coming 233 00:11:17.050 --> 00:11:20.180 because the earthquakes started migrating down rift again. 234 00:11:20.180 --> 00:11:21.680 They didn't go that far down rift, 235 00:11:21.680 --> 00:11:23.240 but they went far enough that we thought, 236 00:11:23.240 --> 00:11:26.080 okay, the next fissures could be down rift. 237 00:11:26.080 --> 00:11:28.620 Sure enough, fissure 13 opened here, 238 00:11:28.620 --> 00:11:31.913 14 and then the rest opened sequentially down rift. 239 00:11:33.160 --> 00:11:34.490 Fissure 17 is offset. 240 00:11:34.490 --> 00:11:37.880 It's the only one offset majorly on the whole trend. 241 00:11:37.880 --> 00:11:41.509 And here's a video of what that looks like and sounds like. 242 00:11:41.509 --> 00:11:44.787 (fissure roaring) 243 00:11:44.787 --> 00:11:47.704 (fissure blasting) 244 00:11:48.675 --> 00:11:52.140 So that was a cannon shot sound that it was making. 245 00:11:52.140 --> 00:11:53.700 At the peak of its activity, 246 00:11:53.700 --> 00:11:55.890 it was doing that every five to 10 minutes 247 00:11:55.890 --> 00:11:58.720 and you could hear that for several miles 248 00:11:58.720 --> 00:12:00.490 away from the fissure. 249 00:12:00.490 --> 00:12:02.840 This was a very interesting fissure 250 00:12:02.840 --> 00:12:04.990 because not only was it offset, 251 00:12:04.990 --> 00:12:07.130 but it was erupting a slightly different composition, 252 00:12:07.130 --> 00:12:08.490 which we didn't know up front, 253 00:12:08.490 --> 00:12:10.550 but we assumed something was different 254 00:12:10.550 --> 00:12:13.623 because none of the other fissures were making this feature. 255 00:12:15.150 --> 00:12:17.970 We'll talk more about the chemistry of this later 256 00:12:17.970 --> 00:12:19.700 in the talk, but essentially, 257 00:12:19.700 --> 00:12:23.213 this is a more evolved basalt, a basaltic andesite. 258 00:12:24.390 --> 00:12:28.120 This more explosive area was just an andesite, 259 00:12:28.120 --> 00:12:31.373 there was no basaltic component to it, it was just andesite. 260 00:12:34.330 --> 00:12:37.420 May 14th to 18th, the rest of the fissures, 261 00:12:37.420 --> 00:12:41.483 up through fissure 23, began opening up rift again. 262 00:12:42.920 --> 00:12:46.030 So the thought is that the earthquakes came down, 263 00:12:46.030 --> 00:12:48.000 something was preventing them from moving farther, 264 00:12:48.000 --> 00:12:50.300 the dike was able to fill that crack 265 00:12:50.300 --> 00:12:52.560 that they had created and erupt in here. 266 00:12:52.560 --> 00:12:55.710 Then the earthquakes were able to break open the rock 267 00:12:55.710 --> 00:12:58.360 and free up some more space, and the magma moved down here. 268 00:12:58.360 --> 00:13:00.170 Once that couldn't move forward anymore, 269 00:13:00.170 --> 00:13:02.783 it starts filling up and backing up up rift. 270 00:13:04.000 --> 00:13:07.693 Fissure 24, over here, opened on May 27th. 271 00:13:09.130 --> 00:13:11.550 That was because of a series of reactivations 272 00:13:11.550 --> 00:13:13.350 that finally went from fissure 17 273 00:13:13.350 --> 00:13:14.850 all the way back to fissure 8. 274 00:13:16.020 --> 00:13:17.780 Fissure 24 opened for the first time 275 00:13:17.780 --> 00:13:19.940 when fissure 8 reactivated 276 00:13:19.940 --> 00:13:23.053 for its big show in June and July. 277 00:13:26.100 --> 00:13:28.750 This is a slide that one of my colleagues made 278 00:13:28.750 --> 00:13:30.880 showing seismicity in the Lower East Rift Zone, 279 00:13:30.880 --> 00:13:33.170 the south flank area, and the summit. 280 00:13:33.170 --> 00:13:34.920 The key thing I want you to take away from this slide 281 00:13:34.920 --> 00:13:36.630 is that all of the seismic activity 282 00:13:36.630 --> 00:13:38.640 for the Lower East Rift Zone happened 283 00:13:38.640 --> 00:13:40.020 in those first couple days in May, 284 00:13:40.020 --> 00:13:42.790 from April 30th to May 18th. 285 00:13:42.790 --> 00:13:44.650 Then everything kind of went quiet on the rift zone. 286 00:13:44.650 --> 00:13:45.760 There was still some activity, 287 00:13:45.760 --> 00:13:47.470 but compared to what we had just seen 288 00:13:47.470 --> 00:13:50.690 on the Lower East Rift Zone, it was relatively small. 289 00:13:50.690 --> 00:13:52.780 And all of the seismic activity, as you can see, 290 00:13:52.780 --> 00:13:54.980 went to this blue area, which is the summit. 291 00:13:55.950 --> 00:13:57.810 We're not going to talk about that part today, 292 00:13:57.810 --> 00:13:59.520 we're gonna just focus on the lower rift. 293 00:13:59.520 --> 00:14:03.010 But the deformation also did the same thing. 294 00:14:03.010 --> 00:14:05.750 This is based off of InSAR data again, 295 00:14:05.750 --> 00:14:09.240 and while it shows a general subsidence 296 00:14:09.240 --> 00:14:11.283 across the entire East Rift Zone, 297 00:14:12.170 --> 00:14:13.500 it's very small. 298 00:14:13.500 --> 00:14:15.303 It's two centimeters, it's one inch. 299 00:14:16.360 --> 00:14:17.350 Whereas the previous slides, 300 00:14:17.350 --> 00:14:21.110 we were seeing multiple inches of change. 301 00:14:21.110 --> 00:14:23.023 It's all kind of a wash in here. 302 00:14:25.100 --> 00:14:27.170 The interpretation that we came to, eventually, 303 00:14:27.170 --> 00:14:29.760 was that if there's no geophysics, 304 00:14:29.760 --> 00:14:32.230 which usually means the eruption's ending, 305 00:14:32.230 --> 00:14:33.890 and yet we still see lava coming out 306 00:14:33.890 --> 00:14:35.360 and it's actually coming out more 307 00:14:35.360 --> 00:14:37.810 and more vigorously and faster, 308 00:14:37.810 --> 00:14:38.750 what does that mean? 309 00:14:38.750 --> 00:14:41.400 It probably means the conduit is quote, unquote, open. 310 00:14:41.400 --> 00:14:42.696 There's no more resistance 311 00:14:42.696 --> 00:14:45.800 for the lava to flow and try to break rock 312 00:14:45.800 --> 00:14:46.860 to get to the surface. 313 00:14:46.860 --> 00:14:49.330 It has a path from wherever it's coming from 314 00:14:49.330 --> 00:14:51.080 in the rift zone or the summit, 315 00:14:51.080 --> 00:14:54.583 and it has a clear, easy path to fissure 8. 316 00:14:58.060 --> 00:15:00.410 So here is, oh, I should say, 317 00:15:00.410 --> 00:15:02.790 fissure 8 or some of the other fissures 318 00:15:02.790 --> 00:15:05.033 that rejuvenated right before fissure 8. 319 00:15:06.520 --> 00:15:08.860 Here's a video of fissure 20. 320 00:15:08.860 --> 00:15:11.420 This is our second fissure 321 00:15:11.420 --> 00:15:13.610 to show classical Hawaiian fountaining 322 00:15:14.720 --> 00:15:16.642 from a fissure source. 323 00:15:16.642 --> 00:15:18.052 Let's see if this'll play. 324 00:15:18.052 --> 00:15:21.219 (helicopter whirring) 325 00:15:22.687 --> 00:15:24.330 So again, you have multiple fountains 326 00:15:24.330 --> 00:15:26.643 along a single crack erupting magma. 327 00:15:29.820 --> 00:15:31.780 That is producing a lava flow 328 00:15:31.780 --> 00:15:34.360 that is moving quite quickly, oops, sorry, 329 00:15:34.360 --> 00:15:35.360 moving quite quickly 330 00:15:38.130 --> 00:15:42.070 down from fissure 20 and around into a subdivision. 331 00:15:42.070 --> 00:15:44.690 And it covered this area, which was probably 332 00:15:44.690 --> 00:15:48.000 a kilometer or a little more in distance, 333 00:15:48.000 --> 00:15:49.980 within minutes to an hour. 334 00:15:49.980 --> 00:15:52.250 It was moving very fast, 335 00:15:52.250 --> 00:15:54.410 so much so that the helicopter pilot 336 00:15:54.410 --> 00:15:56.720 and I actually got out on the one of these side roads 337 00:15:56.720 --> 00:15:59.310 of the cul de sac and I called Civil Defense 338 00:15:59.310 --> 00:16:02.360 and he went and warned a few people who were still home 339 00:16:02.360 --> 00:16:03.558 that they needed to leave 340 00:16:03.558 --> 00:16:06.733 because this was coming at them very quickly. 341 00:16:09.880 --> 00:16:13.390 All right, so from May 18th, when our geophysics goes quiet 342 00:16:13.390 --> 00:16:16.050 on the lower rift, to May 27th, 343 00:16:16.050 --> 00:16:18.030 right as fissure 8 reactivates, 344 00:16:18.030 --> 00:16:20.893 we have a series of up rift reactivations. 345 00:16:24.060 --> 00:16:26.990 Fissure 17 on May 18th, 19th, was going strong. 346 00:16:26.990 --> 00:16:28.663 It had an 80 meter tall fountain. 347 00:16:31.270 --> 00:16:33.300 Fissures 16 and 18 were also active. 348 00:16:33.300 --> 00:16:37.160 20 and 22 were starting to send their flows down to the sea. 349 00:16:37.160 --> 00:16:39.430 They did that in a day and a half. 350 00:16:39.430 --> 00:16:42.060 As fissure 17 started to shut down, 351 00:16:42.060 --> 00:16:45.320 fissure 19 and 15 started to reactivate. 352 00:16:45.320 --> 00:16:48.160 And then I noticed as 16 and 18 appeared to shut down, 353 00:16:48.160 --> 00:16:49.790 turns out they never quite shut down, 354 00:16:49.790 --> 00:16:52.350 but as they decreased activity, 355 00:16:52.350 --> 00:16:55.040 fissures 6 and 13 started to increase activity, 356 00:16:55.040 --> 00:16:57.300 and they produced a joint lava flow 357 00:16:57.300 --> 00:16:58.683 that also went to the sea. 358 00:16:59.680 --> 00:17:03.160 Then, as fissures 20 and 22 started to shut down, 359 00:17:03.160 --> 00:17:07.400 23, 21 and 7 started producing a flow. 360 00:17:07.400 --> 00:17:09.800 21 and 7 together sent a flow to the north, 361 00:17:09.800 --> 00:17:12.730 towards our geothermal plant, and to the south. 362 00:17:12.730 --> 00:17:15.810 I think had it not filled this pit crater here, 363 00:17:15.810 --> 00:17:17.850 it would have reached the sea as well, 364 00:17:17.850 --> 00:17:20.750 but quite a bit of volume went into this pit crater first. 365 00:17:22.090 --> 00:17:24.390 Then, as everything else shut down, 6, 13, 23, 366 00:17:26.320 --> 00:17:28.690 fissure 8 reactivated on May 27th, 367 00:17:28.690 --> 00:17:31.533 and with that came the new fissure 24. 368 00:17:32.660 --> 00:17:35.910 Once that started flowing and effusing a lava flow, 369 00:17:35.910 --> 00:17:38.783 fissures 7 and 21 just shut down as well. 370 00:17:42.930 --> 00:17:44.610 During that time of reactivation, 371 00:17:44.610 --> 00:17:46.640 as the lower vents shut off, 372 00:17:46.640 --> 00:17:48.380 and that pushes magma to come out 373 00:17:48.380 --> 00:17:51.060 of the next available upper vent, 374 00:17:51.060 --> 00:17:53.835 we saw what's called a graben form. 375 00:17:53.835 --> 00:17:56.570 And that is, if you think of a keystone in an archway, 376 00:17:56.570 --> 00:17:58.490 a graben is essentially that kind of a shape 377 00:17:58.490 --> 00:18:01.990 and it drops down as magma ascends. 378 00:18:01.990 --> 00:18:03.520 This one is fairly small. 379 00:18:03.520 --> 00:18:06.670 It's 100 meters, or a football field, across. 380 00:18:06.670 --> 00:18:09.963 But it dropped about two meters, or a little over six feet, 381 00:18:11.290 --> 00:18:13.130 over the course of two or three days. 382 00:18:13.130 --> 00:18:15.690 And the reason that these grabens form 383 00:18:15.690 --> 00:18:17.150 is when magma is trying to rise, 384 00:18:17.150 --> 00:18:19.432 it has to push the walls apart. 385 00:18:19.432 --> 00:18:22.433 So, just like a keystone helps keep a doorway intact, 386 00:18:23.400 --> 00:18:25.060 the ground surface will drop 387 00:18:25.060 --> 00:18:28.630 and behave in much the same way as it's being pushed apart 388 00:18:28.630 --> 00:18:31.793 so the lava, the magma, can reach the surface. 389 00:18:33.120 --> 00:18:36.750 I should mention, sorry, that this is LIDAR based, 390 00:18:36.750 --> 00:18:38.400 because it's a little too fine scale 391 00:18:38.400 --> 00:18:41.030 for the InSAR derived image. 392 00:18:41.030 --> 00:18:42.180 But you can kind of get a hint of it, 393 00:18:42.180 --> 00:18:45.696 there's a few blue spots in the same trend there. 394 00:18:45.696 --> 00:18:48.280 Like I said, this was 100 meters across, 395 00:18:48.280 --> 00:18:49.250 one football field across. 396 00:18:49.250 --> 00:18:51.160 It was several kilometers long. 397 00:18:51.160 --> 00:18:54.210 It stretched essentially from Pohoiki 398 00:18:54.210 --> 00:18:57.883 all the way to Highway 130, through the whole subdivision. 399 00:19:00.100 --> 00:19:01.550 Here's what that looks like. 400 00:19:01.550 --> 00:19:04.193 Over the course of a little more than 24 hours, 401 00:19:05.440 --> 00:19:07.620 and prior to this, it had been just a hairline crack, 402 00:19:07.620 --> 00:19:09.330 turned into a one or two foot crack, 403 00:19:09.330 --> 00:19:12.530 and six inches, 12 inches of downdrop, 404 00:19:12.530 --> 00:19:15.610 to a six or eight foot wide crack 405 00:19:15.610 --> 00:19:18.110 and three or four feet of downdrop. 406 00:19:18.110 --> 00:19:19.660 Like I said, it ultimately reached 407 00:19:19.660 --> 00:19:21.813 about six and 1/2 feet of downdrop. 408 00:19:23.230 --> 00:19:24.300 This happened very fast. 409 00:19:24.300 --> 00:19:26.490 I actually had a resident stop me in the middle 410 00:19:26.490 --> 00:19:28.970 of one of my shifts and say, "Is the ground sinking?" 411 00:19:28.970 --> 00:19:31.023 Yes, actually, the ground is sinking. 412 00:19:31.920 --> 00:19:36.370 That was our cue that a lot more magma was about to come out 413 00:19:36.370 --> 00:19:39.813 of whichever fissure it chose as the easiest path. 414 00:19:42.120 --> 00:19:46.993 That was fissure 8, and it was active for two months. 415 00:19:48.020 --> 00:19:52.493 It started its first rejuvenated flow May 27th. 416 00:19:53.530 --> 00:19:56.042 It lasted until August 5th. 417 00:19:56.042 --> 00:19:58.040 In this picture, which was taken a month 418 00:19:58.040 --> 00:20:00.480 into that time frame, on June 26th, 419 00:20:00.480 --> 00:20:02.970 you can see how long and how wide it is. 420 00:20:02.970 --> 00:20:05.840 Right here, this red line is a half mile wide, 421 00:20:05.840 --> 00:20:07.583 or 800 meters across. 422 00:20:09.720 --> 00:20:11.190 The flow came up Luana Street 423 00:20:11.190 --> 00:20:14.140 and then made a bend to the northeast here in this picture. 424 00:20:15.540 --> 00:20:17.950 It went eight miles, or 13 kilometers, 425 00:20:17.950 --> 00:20:20.700 until it reached the sea, and it did that in five days. 426 00:20:24.040 --> 00:20:26.290 The average eruption rate for those two months 427 00:20:26.290 --> 00:20:29.330 was approximately 100 cubic meters per second. 428 00:20:29.330 --> 00:20:32.450 And to put that into terms that we might recognize, 429 00:20:32.450 --> 00:20:34.370 for those of you who have come to these talks a lot 430 00:20:34.370 --> 00:20:36.493 and think about Pu'u 'O'o a lot, 431 00:20:37.440 --> 00:20:39.130 fissure 8 erupted five years' worth 432 00:20:39.130 --> 00:20:41.783 of Pu'u 'O'o material in two months. 433 00:20:43.072 --> 00:20:46.020 That works out to about a cubic kilometer 434 00:20:46.020 --> 00:20:50.913 of uncorrected, effused material. 435 00:20:52.031 --> 00:20:53.673 We haven't corrected for the density in that. 436 00:20:55.780 --> 00:20:57.260 But fissure 8 wasn't done. 437 00:20:57.260 --> 00:20:59.550 Even though the channel drained, 438 00:20:59.550 --> 00:21:02.200 the effusion rate dropped dramatically on August 4th. 439 00:21:04.730 --> 00:21:07.010 The channel drained on August 5th, 440 00:21:07.010 --> 00:21:09.730 and there was still a little bit of lava 441 00:21:09.730 --> 00:21:11.740 inside the cone from August 6th to 15th. 442 00:21:11.740 --> 00:21:16.740 There were still a few ooze-outs and ocean entry toes, 443 00:21:17.652 --> 00:21:19.860 as well, during this period. 444 00:21:19.860 --> 00:21:22.593 But there was nothing in the channel by August 6th. 445 00:21:24.390 --> 00:21:25.930 Then lava went away for a while. 446 00:21:25.930 --> 00:21:29.527 So again, we were asking ourselves, "Is this it? 447 00:21:29.527 --> 00:21:30.360 "Is there more coming? 448 00:21:30.360 --> 00:21:31.467 "Is this just a break? 449 00:21:31.467 --> 00:21:32.647 "How will we know?" 450 00:21:33.690 --> 00:21:36.217 Lava came back one last time September 1st to 5th. 451 00:21:37.670 --> 00:21:39.120 It was very weakly active. 452 00:21:39.120 --> 00:21:41.110 It stayed within the fissure 8 cone. 453 00:21:41.110 --> 00:21:46.110 And this is a video showing just how weak it's spattering. 454 00:21:46.420 --> 00:21:48.330 There's a nice breakout here, 455 00:21:48.330 --> 00:21:50.503 with the crust being pushed off. 456 00:21:53.260 --> 00:21:54.660 But it didn't make it into the spillway, 457 00:21:54.660 --> 00:21:56.210 it didn't reoccupy the channel. 458 00:21:58.480 --> 00:22:01.560 Then it drained away as quietly as it came back. 459 00:22:01.560 --> 00:22:04.483 That was finally the end of the eruption. 460 00:22:06.700 --> 00:22:08.090 So that brings us to 2019, 461 00:22:08.090 --> 00:22:09.740 which is what this talk is usually about, 462 00:22:09.740 --> 00:22:12.640 the past year of what's been going on. 463 00:22:12.640 --> 00:22:15.100 We can summarize it in just one or two slides because, 464 00:22:15.100 --> 00:22:16.500 thankfully, it's been quiet. 465 00:22:17.480 --> 00:22:20.110 But the unfortunate thing is that some residents 466 00:22:20.110 --> 00:22:24.190 are still feeling the thermal effects of the intrusion. 467 00:22:24.190 --> 00:22:25.650 As the dike is trying to cool, 468 00:22:25.650 --> 00:22:29.050 the heat is moving into the surrounding ground. 469 00:22:29.050 --> 00:22:30.829 So this is one resident's property. 470 00:22:30.829 --> 00:22:32.770 There's a breadfruit tree right here. 471 00:22:32.770 --> 00:22:34.010 That was the first crack 472 00:22:34.010 --> 00:22:36.060 on this particular resident's property, 473 00:22:36.060 --> 00:22:38.070 and it was also the first steaming area. 474 00:22:38.070 --> 00:22:41.030 We thought this was actually going to erupt at one point 475 00:22:41.030 --> 00:22:42.390 because it had a blue tinge to it, 476 00:22:42.390 --> 00:22:44.813 which means there's sulfur dioxide mixed into that, 477 00:22:46.320 --> 00:22:47.700 but it never erupted. 478 00:22:47.700 --> 00:22:49.930 However, a year later, 479 00:22:49.930 --> 00:22:52.000 this is the same breadfruit tree, 480 00:22:52.000 --> 00:22:54.570 all of her vegetation has essentially been boiled 481 00:22:54.570 --> 00:22:56.360 and dissolved away by the groundwater 482 00:22:56.360 --> 00:22:58.613 that is so hot from this intrusion. 483 00:23:00.330 --> 00:23:03.500 So you can see it used to be a very nice lush green field 484 00:23:03.500 --> 00:23:05.090 and by time we took this picture, 485 00:23:05.090 --> 00:23:06.223 parts of it had died. 486 00:23:07.898 --> 00:23:10.420 But now, the plants literally just fell on the ground 487 00:23:10.420 --> 00:23:13.530 as their roots boiled and then they dissolved themselves. 488 00:23:13.530 --> 00:23:17.190 And it leaves this little white crust behind on the rock. 489 00:23:17.190 --> 00:23:18.790 So those residents are in Ala'ili, 490 00:23:18.790 --> 00:23:20.030 and they've been feeling this 491 00:23:20.030 --> 00:23:22.920 for the better part of a year and a half now. 492 00:23:22.920 --> 00:23:25.300 This started for them during the eruption. 493 00:23:25.300 --> 00:23:27.220 They saw it progress through the eruption 494 00:23:27.220 --> 00:23:29.820 and it's just been getting worse after the eruption. 495 00:23:30.920 --> 00:23:33.550 But recently, Halekamahina residents have called us 496 00:23:33.550 --> 00:23:36.040 and said they started noticing some similar effects 497 00:23:36.040 --> 00:23:40.310 that we recognized from Ala'ili this fall, 498 00:23:40.310 --> 00:23:42.443 so for the last five or six months. 499 00:23:43.860 --> 00:23:46.200 Then Leilani Estates called in December 500 00:23:46.200 --> 00:23:49.027 and said, "Hey, folks next to fissures 9 and 10 501 00:23:49.027 --> 00:23:50.047 "are noticing the temperatures 502 00:23:50.047 --> 00:23:53.010 "on their property are rising, is everything okay?" 503 00:23:53.010 --> 00:23:56.570 And the unfortunate answer is, yes, everything is okay. 504 00:23:56.570 --> 00:23:58.550 But here's what's happening. 505 00:23:58.550 --> 00:23:59.730 Well, here's the areas that are affected. 506 00:23:59.730 --> 00:24:02.450 This is the Ala'ili area. 507 00:24:02.450 --> 00:24:04.100 This was the Leilani Estates area 508 00:24:04.100 --> 00:24:06.000 that was recently affected. 509 00:24:06.000 --> 00:24:07.973 And this is the Halekamahina area. 510 00:24:09.610 --> 00:24:12.530 So in our geologic cartoon, we have a dike 511 00:24:12.530 --> 00:24:13.920 that's coming up to the surface. 512 00:24:13.920 --> 00:24:15.610 It doesn't break the surface in this cartoon, 513 00:24:15.610 --> 00:24:16.770 it's just an intrusion 514 00:24:17.960 --> 00:24:20.173 to help conceptually with the process. 515 00:24:21.960 --> 00:24:25.430 Thermally, right above the intrusion is very hot, 516 00:24:25.430 --> 00:24:27.340 magmatic temperature hot. 517 00:24:27.340 --> 00:24:29.700 Hot steam coming out of this crack. 518 00:24:29.700 --> 00:24:33.892 We're talking anywhere from 200 to 500 Celsius, so very hot, 519 00:24:33.892 --> 00:24:37.300 much higher above the boiling temperature 520 00:24:37.300 --> 00:24:39.960 than anyone would want to approach. 521 00:24:39.960 --> 00:24:43.090 But just a few yards away, 20, 30 yards away, 522 00:24:43.090 --> 00:24:46.060 the ground feels normal, feels cool. 523 00:24:46.060 --> 00:24:47.020 It doesn't feel hot at all. 524 00:24:47.020 --> 00:24:49.800 It's just these cracks that are really hot. 525 00:24:49.800 --> 00:24:53.270 But fast forward whatever time frame you want, 526 00:24:53.270 --> 00:24:57.570 six months, a year, this heat will slowly start leaching 527 00:24:57.570 --> 00:24:59.040 into the ground rock. 528 00:24:59.040 --> 00:25:01.563 And this spot will cool down, 529 00:25:02.420 --> 00:25:04.950 but these spots will warm up. 530 00:25:04.950 --> 00:25:07.450 So, this has basically cooled to the boiling point, 531 00:25:07.450 --> 00:25:09.310 it seems to be buffered there. 532 00:25:09.310 --> 00:25:12.010 We haven't seen the temperatures change on these properties 533 00:25:12.010 --> 00:25:14.353 above or below the boiling point too much. 534 00:25:15.570 --> 00:25:18.500 But now, that 20 yards away that used to be cool, 535 00:25:18.500 --> 00:25:21.210 also has steaming water and is just shy 536 00:25:21.210 --> 00:25:22.830 of the boiling point. 537 00:25:22.830 --> 00:25:24.610 That's because the heat from this dike 538 00:25:24.610 --> 00:25:27.050 is slowly migrating outwards into the ground 539 00:25:27.050 --> 00:25:30.253 as this tries to solidify and crystallize. 540 00:25:31.610 --> 00:25:34.100 But unfortunately, that means that farther areas away 541 00:25:34.100 --> 00:25:36.270 that you thought wouldn't be impacted at all 542 00:25:36.270 --> 00:25:39.520 by the heat are now starting to warm up. 543 00:25:39.520 --> 00:25:42.240 So, a lot of residents in these affected areas 544 00:25:42.240 --> 00:25:45.090 are asking themselves, well, is there anything we can do? 545 00:25:46.460 --> 00:25:47.360 What should we do? 546 00:25:49.260 --> 00:25:50.320 Unfortunately, our best guidance 547 00:25:50.320 --> 00:25:52.750 is the 1955 eruption where there were steam vents 548 00:25:52.750 --> 00:25:55.440 that were still warm and spa attractions 549 00:25:55.440 --> 00:25:57.663 as recently as 2017, 2018. 550 00:25:59.029 --> 00:26:02.120 So, it can stay hot for several decades. 551 00:26:02.120 --> 00:26:06.050 That's just how the heat is trying to leave the dike 552 00:26:06.050 --> 00:26:08.043 so that it can solidify fully. 553 00:26:11.500 --> 00:26:13.470 As I mentioned at the beginning, 554 00:26:13.470 --> 00:26:15.680 this eruption was unprecedented for Kilauea 555 00:26:15.680 --> 00:26:18.083 in the past 200 years of its activity. 556 00:26:19.780 --> 00:26:22.300 The total flow field area, which is in pink here, 557 00:26:22.300 --> 00:26:25.490 was 13.7 square miles. 558 00:26:25.490 --> 00:26:28.460 The new lava delta area, this was the old shoreline 559 00:26:28.460 --> 00:26:30.800 that's dashed here, so this area 560 00:26:30.800 --> 00:26:34.783 that extends out into the sea, is 875 acres. 561 00:26:37.870 --> 00:26:40.393 I think that's all I wanted to say on this slide. 562 00:26:41.730 --> 00:26:44.830 It was the most voluminous eruption for two months 563 00:26:44.830 --> 00:26:47.463 of time in the past 200 years. 564 00:26:47.463 --> 00:26:51.223 Pu'u 'O'o did erupt more volume, but it was over 35 years. 565 00:26:52.120 --> 00:26:54.420 It's the highest sustained lava discharge rate 566 00:26:54.420 --> 00:26:56.574 ever measured from Kilauea. 567 00:26:56.574 --> 00:26:59.603 And it's the highest SO2 rates measured at Kilauea. 568 00:27:00.870 --> 00:27:02.240 In addition, the 6.9 earthquake 569 00:27:02.240 --> 00:27:04.663 was the largest we'd had since 1975. 570 00:27:06.140 --> 00:27:08.840 Let's talk about the gas for just a slide or two here. 571 00:27:10.770 --> 00:27:14.550 Our gas team started measuring SO2 output 572 00:27:14.550 --> 00:27:17.440 from Kilauea in 1979. 573 00:27:17.440 --> 00:27:20.280 When the Pu'u 'O'o eruption started in 1983, 574 00:27:20.280 --> 00:27:22.950 we averaged about one megaton, or one million tons 575 00:27:22.950 --> 00:27:24.283 of SO2 per year. 576 00:27:26.380 --> 00:27:31.190 When the summit eruption and the lava lake started in 2008, 577 00:27:31.190 --> 00:27:33.520 that bumped up to two to three million tons 578 00:27:33.520 --> 00:27:37.033 of sulfur dioxide per year from Kilauea. 579 00:27:37.870 --> 00:27:40.040 However, you can see this giant bar over here 580 00:27:40.040 --> 00:27:44.290 on the side of the plot, and that is solely 2018, 581 00:27:44.290 --> 00:27:47.080 and that is solely from the lower rift zone. 582 00:27:47.080 --> 00:27:49.230 When that eruption started in May, 583 00:27:49.230 --> 00:27:51.520 and especially as it picked up in June, 584 00:27:51.520 --> 00:27:55.500 the other summit and Pu'u 'O'o areas basically dropped 585 00:27:55.500 --> 00:27:58.593 to zero sulfur dioxide output. 586 00:27:59.540 --> 00:28:01.670 It was within the noise, so they, 587 00:28:01.670 --> 00:28:03.410 we weren't sure if we were actually getting a reading 588 00:28:03.410 --> 00:28:05.920 or if it's just within the noise. 589 00:28:05.920 --> 00:28:10.920 So, 10 million tons of sulfur for the year 590 00:28:11.010 --> 00:28:14.890 came out of Leilani Estates. 591 00:28:14.890 --> 00:28:16.793 And 2019 is down there, 592 00:28:18.791 --> 00:28:21.340 13,000 tons for the year. 593 00:28:21.340 --> 00:28:22.870 Much reduced. 594 00:28:22.870 --> 00:28:24.910 We've had the best air quality on this island 595 00:28:24.910 --> 00:28:26.437 that we've had in a long time, 596 00:28:26.437 --> 00:28:29.370 and that is the lowest rate since these measurements 597 00:28:29.370 --> 00:28:32.203 have started being recorded by our gas team. 598 00:28:36.430 --> 00:28:37.263 There we go. 599 00:28:37.263 --> 00:28:39.250 Okay, so that's kind of the summary of the past year 600 00:28:39.250 --> 00:28:41.580 and the 2018 eruption. 601 00:28:41.580 --> 00:28:44.483 Very short and to the point. 602 00:28:46.550 --> 00:28:49.340 HVO has been using this quiet year, A, 603 00:28:49.340 --> 00:28:50.790 to move into our temporary facility, 604 00:28:50.790 --> 00:28:53.350 but B, to start addressing some of these questions 605 00:28:53.350 --> 00:28:55.930 and gain some insights on what happened and why, 606 00:28:55.930 --> 00:29:00.930 and try to find some answers so we can understand future 607 00:29:01.030 --> 00:29:03.470 potential eruption crises better. 608 00:29:03.470 --> 00:29:04.670 We touched on this already. 609 00:29:04.670 --> 00:29:05.653 What does it mean when the seismicity 610 00:29:05.653 --> 00:29:07.170 and the deformation stop, 611 00:29:07.170 --> 00:29:09.473 even though the lava's still flowing? 612 00:29:11.570 --> 00:29:12.910 It means the conduit is open 613 00:29:12.910 --> 00:29:15.760 and that there's likely more material coming. 614 00:29:15.760 --> 00:29:19.370 Until we see some other sign, like the gas drop 615 00:29:19.370 --> 00:29:22.600 or the lava just stops coming out, 616 00:29:22.600 --> 00:29:24.010 it's really a fluid dynamic 617 00:29:24.010 --> 00:29:27.460 and a magma static head that's continuing 618 00:29:27.460 --> 00:29:30.553 that material to erupt. 619 00:29:33.430 --> 00:29:37.060 How does magmatic chemical variation affect eruptions? 620 00:29:37.060 --> 00:29:38.900 'Cause it's not, this first point is really 621 00:29:38.900 --> 00:29:40.280 about the structure of the volcano, 622 00:29:40.280 --> 00:29:42.850 but there's more that controls an eruption 623 00:29:42.850 --> 00:29:43.770 than just the structure. 624 00:29:43.770 --> 00:29:45.480 There's also the chemistry. 625 00:29:45.480 --> 00:29:47.210 In this work, I've taken a few slides 626 00:29:47.210 --> 00:29:50.270 from our colleague Cheryl Gansecki at UH Hilo. 627 00:29:50.270 --> 00:29:52.360 She did a fantastic job during the eruption 628 00:29:52.360 --> 00:29:55.089 with her colleagues and with HVO, 629 00:29:55.089 --> 00:29:57.410 essentially doing petrology real-time. 630 00:29:57.410 --> 00:29:59.070 She kind of pioneered that 631 00:29:59.070 --> 00:30:01.935 with the proof of concept in this eruption. 632 00:30:01.935 --> 00:30:04.520 Let's look at how different chemistries 633 00:30:06.130 --> 00:30:07.860 affect what the eruption does. 634 00:30:07.860 --> 00:30:10.110 This is a repeat from her talk last Thursday night. 635 00:30:10.110 --> 00:30:10.943 If any of you were there, 636 00:30:10.943 --> 00:30:13.470 you'll recognize a few of these slides. 637 00:30:13.470 --> 00:30:16.373 Again, we can look back to the 1955 eruption 638 00:30:16.373 --> 00:30:18.120 that was in the same area. 639 00:30:18.120 --> 00:30:20.853 Our 2018 eruption was kind of in this gap right here. 640 00:30:22.640 --> 00:30:26.720 They noted in 1955 that the lavas seemed cool, 641 00:30:26.720 --> 00:30:29.230 and that they might have been stored for a while. 642 00:30:29.230 --> 00:30:32.450 They had some more crystals, they're sticky and viscous, 643 00:30:32.450 --> 00:30:34.913 like our first 15 fissures were in 2018. 644 00:30:36.380 --> 00:30:39.680 The lava produced later on in the 1955 eruption 645 00:30:39.680 --> 00:30:44.340 was more hot and fluid and covered a lot more area, 646 00:30:44.340 --> 00:30:46.543 as was the case in 2018, as well. 647 00:30:48.780 --> 00:30:51.470 So we're back to these little pods of magma 648 00:30:51.470 --> 00:30:53.660 that are stored in the rift zone. 649 00:30:53.660 --> 00:30:55.500 Why are they stored there? 650 00:30:55.500 --> 00:30:57.350 Well, any eruption that happens 651 00:30:57.350 --> 00:30:59.870 never erupts 100% of its material. 652 00:30:59.870 --> 00:31:02.560 There's always something that's left behind. 653 00:31:02.560 --> 00:31:05.653 Depending on how warm that something can stay, 654 00:31:06.830 --> 00:31:08.783 it could be remobilized later. 655 00:31:10.130 --> 00:31:12.560 We call these magma storage regions. 656 00:31:12.560 --> 00:31:14.260 There's one under Makaopuhi Crater 657 00:31:14.260 --> 00:31:16.313 that drained during this event. 658 00:31:17.170 --> 00:31:18.220 There are probably numerous others 659 00:31:18.220 --> 00:31:19.180 that we don't even know about, 660 00:31:19.180 --> 00:31:22.213 but there are a half dozen or so that we do know about. 661 00:31:24.030 --> 00:31:25.880 It's likely residue from earlier eruptions, 662 00:31:25.880 --> 00:31:28.160 and for the 2018 eruption, 663 00:31:28.160 --> 00:31:31.950 the chemistry seems to match an evolved 1955. 664 00:31:31.950 --> 00:31:34.810 So, the 2018 material came in, but to get out, 665 00:31:34.810 --> 00:31:38.883 first it had to push out what was left of the 1955 magma. 666 00:31:42.330 --> 00:31:44.500 Yeah, so when the magma is in the rift zone, 667 00:31:44.500 --> 00:31:47.080 it's not, without an intrusion to help push it along, 668 00:31:47.080 --> 00:31:49.270 it's not going to erupt again on its own, 669 00:31:49.270 --> 00:31:53.660 which gives it time to cool and crystallize and solidify. 670 00:31:53.660 --> 00:31:57.380 But, as we know, since we erupted evolved 1955, 671 00:31:57.380 --> 00:31:59.590 that process can easily take seven decades. 672 00:31:59.590 --> 00:32:01.740 That's how long this has been sitting there, 673 00:32:01.740 --> 00:32:02.840 and it came out again. 674 00:32:04.890 --> 00:32:07.553 All right, so here's one of Cheryl's chemistry plots. 675 00:32:08.540 --> 00:32:09.470 Don't be intimidated. 676 00:32:09.470 --> 00:32:11.500 It's actually really easy. 677 00:32:11.500 --> 00:32:15.550 She's looking at calcium oxide as a proxy for temperature. 678 00:32:15.550 --> 00:32:17.460 So, she's measuring this 679 00:32:17.460 --> 00:32:20.000 and and she can determine the temperature 680 00:32:20.000 --> 00:32:23.420 of the lava that it erupts at. 681 00:32:23.420 --> 00:32:26.240 So fissures 1-15, here in the yellow, 682 00:32:26.240 --> 00:32:28.610 all erupted pretty cool for Kilauea, 683 00:32:28.610 --> 00:32:31.753 so around 1,110 Celsius. 684 00:32:32.780 --> 00:32:36.010 Normal composition from Pu'u 'O'o just a month prior 685 00:32:36.010 --> 00:32:38.440 to this event is up here. 686 00:32:38.440 --> 00:32:41.820 So, this is kinda cool, a cooler temperature. 687 00:32:41.820 --> 00:32:44.450 Fissure 16, we're just gonna skip 17 for a second, 688 00:32:44.450 --> 00:32:47.540 and 18, 19, 20, were a little warmer. 689 00:32:47.540 --> 00:32:49.570 And as you remember that was as we started 690 00:32:49.570 --> 00:32:52.140 to turn the page from sticky magma 691 00:32:52.140 --> 00:32:56.433 into more fluid and less viscous magma and hotter magma. 692 00:32:58.530 --> 00:33:02.583 Then, when our geophysics die away in the lower rift, 693 00:33:03.690 --> 00:33:06.610 we start seeing lava temperatures that are much hotter. 694 00:33:06.610 --> 00:33:08.750 They're not quite Pu'u 'O'o temperatures, 695 00:33:08.750 --> 00:33:10.083 they're just shy of it. 696 00:33:11.130 --> 00:33:13.120 That remains true for the rest of the eruption, 697 00:33:13.120 --> 00:33:14.540 when fissure 8 turns on 698 00:33:14.540 --> 00:33:17.320 and for the whole time that was active. 699 00:33:17.320 --> 00:33:19.640 So why is that a little cooler than Pu'u 'O'o 700 00:33:19.640 --> 00:33:21.930 if we think Pu'u 'O'o material 701 00:33:21.930 --> 00:33:24.180 is actually coming out at this point? 702 00:33:24.180 --> 00:33:26.500 Well, it has to travel twice as far, 703 00:33:26.500 --> 00:33:28.740 so it's gonna lose just a fraction of its heat 704 00:33:28.740 --> 00:33:30.213 in that transit underground. 705 00:33:31.230 --> 00:33:33.670 Now, fissure 17. 706 00:33:33.670 --> 00:33:34.920 Let's talk about that. 707 00:33:34.920 --> 00:33:38.443 So that erupted really cold for lava, 708 00:33:39.780 --> 00:33:41.093 especially from Kilauea. 709 00:33:43.380 --> 00:33:45.800 Fissure 17 did that. 710 00:33:45.800 --> 00:33:50.480 This is the initial fissure 17 samples. 711 00:33:50.480 --> 00:33:55.480 Later in its life, before it totally waned away, 712 00:33:55.700 --> 00:33:57.100 it did warm up a little bit. 713 00:33:58.010 --> 00:34:00.350 But this is, again, because of that chemistry issue. 714 00:34:00.350 --> 00:34:04.780 These are all, this is evolved 1955 basalt 715 00:34:04.780 --> 00:34:06.060 that's getting pushed out. 716 00:34:06.060 --> 00:34:08.840 This is basalt that we're used to seeing from Pu'u 'O'o 717 00:34:08.840 --> 00:34:11.770 and maybe even a little bit from the summit. 718 00:34:11.770 --> 00:34:14.210 But this is basaltic andesite and andesite, 719 00:34:14.210 --> 00:34:16.793 it's just naturally a slightly colder magma. 720 00:34:19.660 --> 00:34:21.070 Since it's sitting in the rift zone, 721 00:34:21.070 --> 00:34:24.310 and we don't know from what eruption it came from. 722 00:34:24.310 --> 00:34:26.580 There are some options, but I'm not sure 723 00:34:26.580 --> 00:34:29.030 that Cheryl and her group has pinned it down yet. 724 00:34:30.420 --> 00:34:32.920 The magma is not only cooling, but it has time to evolve. 725 00:34:32.920 --> 00:34:37.210 As crystals form, they leave behind the silica dioxide, 726 00:34:37.210 --> 00:34:38.300 and that's the difference 727 00:34:38.300 --> 00:34:39.570 between a basalt and an andesite 728 00:34:39.570 --> 00:34:44.570 is how much silica dioxide is in the liquid rock. 729 00:34:44.640 --> 00:34:47.692 The more silica, the more viscous it is. 730 00:34:47.692 --> 00:34:51.080 The more viscous it is, the more explosive it is. 731 00:34:51.080 --> 00:34:55.270 So new eruptions can push out the older magma, 732 00:34:55.270 --> 00:34:56.880 but it does come with the consequence 733 00:34:56.880 --> 00:34:59.363 of potentially increased hazards. 734 00:35:00.960 --> 00:35:02.520 That's our insight number two. 735 00:35:02.520 --> 00:35:04.450 New magma types can lead to new eruption styles, 736 00:35:04.450 --> 00:35:06.850 like the big explosive boomer that you saw 737 00:35:06.850 --> 00:35:09.580 and the cannon shot that that produced, 738 00:35:09.580 --> 00:35:12.060 but it also comes with the hazards that that produces, 739 00:35:12.060 --> 00:35:14.360 where lava bombs are flying much farther 740 00:35:14.360 --> 00:35:16.280 than they otherwise would've. 741 00:35:16.280 --> 00:35:19.320 This is a slightly denser rock. 742 00:35:19.320 --> 00:35:21.290 It punctured through a roof, I believe, 743 00:35:21.290 --> 00:35:24.953 and a wall, and unfortunately, broke someone's leg. 744 00:35:27.310 --> 00:35:28.530 It had some extra hazards 745 00:35:28.530 --> 00:35:31.503 that you wouldn't think of for basaltic eruptions. 746 00:35:34.410 --> 00:35:36.380 Okay, next question. 747 00:35:36.380 --> 00:35:39.090 Why did the fissure 8 fountain pulse? 748 00:35:39.090 --> 00:35:40.720 Matt and I, and many of our colleagues, 749 00:35:40.720 --> 00:35:43.370 noticed that several of the fountains, 750 00:35:43.370 --> 00:35:45.490 but especially the fissure 8 fountain, 751 00:35:45.490 --> 00:35:46.620 was sitting there doing its thing, 752 00:35:46.620 --> 00:35:47.910 but it would go up and down, 753 00:35:47.910 --> 00:35:50.220 on like every five to 10 minutes. 754 00:35:50.220 --> 00:35:51.250 The question was why? 755 00:35:51.250 --> 00:35:53.310 What is that all about? 756 00:35:53.310 --> 00:35:56.450 So the next few slides are from Matt's talk from last year, 757 00:35:56.450 --> 00:35:59.060 and some of his new work 758 00:35:59.060 --> 00:36:01.103 that we copublished together this year. 759 00:36:03.182 --> 00:36:04.015 So this is a video. 760 00:36:04.015 --> 00:36:05.670 He sped it up five times. 761 00:36:05.670 --> 00:36:08.020 This was courtesy of our UAS team 762 00:36:08.020 --> 00:36:09.610 that was here during the eruption. 763 00:36:09.610 --> 00:36:12.460 They are USGS, not HVO-specific, 764 00:36:12.460 --> 00:36:15.580 but they were a huge help in monitoring the eruption. 765 00:36:15.580 --> 00:36:18.620 You can see that, at times, fissure 8, which is here, 766 00:36:18.620 --> 00:36:21.120 is sending a lot of material through this spillway 767 00:36:21.120 --> 00:36:23.440 into the channel, which starts about here. 768 00:36:23.440 --> 00:36:24.720 We're getting some convection, 769 00:36:24.720 --> 00:36:26.772 it looks like turbulent flow. 770 00:36:26.772 --> 00:36:28.940 Then, after five or 10 minutes, 771 00:36:28.940 --> 00:36:29.960 remember this was sped up, 772 00:36:29.960 --> 00:36:33.110 so it's gonna be a few seconds here, it slows down. 773 00:36:33.110 --> 00:36:34.430 We start seeing more crust 774 00:36:34.430 --> 00:36:37.060 and we lose our turbulent eddies, 775 00:36:37.060 --> 00:36:39.223 they're almost all gone except for that one. 776 00:36:40.540 --> 00:36:42.448 It stays like this, nice and calm 777 00:36:42.448 --> 00:36:45.510 and flowing a little more slowly. 778 00:36:45.510 --> 00:36:47.133 And then it'll speed up again. 779 00:36:49.592 --> 00:36:50.690 Matt finally wrapped his head around it 780 00:36:50.690 --> 00:36:53.020 and was able to figure out that this is very similar 781 00:36:53.020 --> 00:36:56.780 to a process that we've seen before called gas pistoning. 782 00:36:56.780 --> 00:36:58.960 The only difference is that gas pistoning, 783 00:36:58.960 --> 00:37:01.097 when we've seen it at Mauna Ulu, and at Pu'u 'O'o, 784 00:37:01.097 --> 00:37:05.851 and Halema'uma'u, it's confined, it's in a pit. 785 00:37:05.851 --> 00:37:07.270 So, you see the lava rise up. 786 00:37:07.270 --> 00:37:09.670 Then when the gas can finally break the surface, 787 00:37:09.670 --> 00:37:12.220 the gas all comes out and the lava drops back down. 788 00:37:13.340 --> 00:37:16.650 It's a cyclic rise and fall of the lava surface, 789 00:37:16.650 --> 00:37:19.473 depending on the gas build-up and the gas release. 790 00:37:20.600 --> 00:37:21.910 But if you're in a fountain 791 00:37:21.910 --> 00:37:25.130 that has a spillway where lava can leave, 792 00:37:25.130 --> 00:37:27.040 and it's not confined, 793 00:37:27.040 --> 00:37:29.223 it manifests itself a little differently. 794 00:37:30.610 --> 00:37:33.200 Matt was able, after watching hours and hours of video 795 00:37:33.200 --> 00:37:35.010 and tediously analyzing it, 796 00:37:35.010 --> 00:37:36.010 he was able to figure out 797 00:37:36.010 --> 00:37:38.300 that as the fountain height goes up, 798 00:37:38.300 --> 00:37:40.060 more SO2 comes out of the fountain, 799 00:37:40.060 --> 00:37:42.600 so our gas flux goes up. 800 00:37:42.600 --> 00:37:44.283 And the seismic tremor goes up. 801 00:37:46.280 --> 00:37:47.330 Keep in mind, this is all smaller 802 00:37:47.330 --> 00:37:50.283 than the early May seismic tremor, but it is still there. 803 00:37:52.220 --> 00:37:54.400 As a result of that, the lava level 804 00:37:54.400 --> 00:37:55.950 in the channel goes down, 805 00:37:55.950 --> 00:37:58.041 and the bulk effusion rate goes down, 806 00:37:58.041 --> 00:38:01.210 and the velocity of the lava in the channel goes down. 807 00:38:01.210 --> 00:38:03.730 But when the fountains start to die away, 808 00:38:03.730 --> 00:38:04.690 well, they don't die away, 809 00:38:04.690 --> 00:38:05.993 but as they start to wane, 810 00:38:07.810 --> 00:38:09.640 and come back down in height, 811 00:38:09.640 --> 00:38:11.300 the SO2 kinda stays trapped 812 00:38:11.300 --> 00:38:13.470 in those fountains a little longer. 813 00:38:13.470 --> 00:38:15.240 The seismic tremor goes down. 814 00:38:15.240 --> 00:38:17.240 The lava level in the channel goes up, 815 00:38:17.240 --> 00:38:18.300 because all of that material, 816 00:38:18.300 --> 00:38:19.840 instead of going up and releasing the gas, 817 00:38:19.840 --> 00:38:22.910 is now coming out and over into the spillway. 818 00:38:22.910 --> 00:38:24.470 So, the bulk effusion rate goes up, 819 00:38:24.470 --> 00:38:26.483 and the velocity in the channel goes up. 820 00:38:27.720 --> 00:38:29.520 This happens on the order of minutes, 821 00:38:29.520 --> 00:38:31.070 roughly every 10 minutes or so, 822 00:38:31.070 --> 00:38:32.540 you can see this change happen. 823 00:38:32.540 --> 00:38:35.190 Sometimes it's more dramatic than others, 824 00:38:35.190 --> 00:38:37.840 but this seems to happen on a cyclic pattern, 825 00:38:37.840 --> 00:38:39.073 just like gas pistoning. 826 00:38:41.530 --> 00:38:42.380 So here's a video of that. 827 00:38:42.380 --> 00:38:45.260 This is the low-flow time where the fountains are high, 828 00:38:45.260 --> 00:38:47.035 just off the screen. 829 00:38:47.035 --> 00:38:50.240 Higher, they got about 50 meters around this time. 830 00:38:50.240 --> 00:38:53.223 And then you'll see it starting to speed up again. 831 00:38:55.180 --> 00:38:56.470 The lava is reaching higher 832 00:38:56.470 --> 00:38:58.270 because the fountains are dropping. 833 00:38:58.270 --> 00:39:00.170 It's coming down the spillway faster, 834 00:39:00.170 --> 00:39:02.650 so it banks up and builds up these ramparts 835 00:39:02.650 --> 00:39:03.500 in the back here. 836 00:39:07.380 --> 00:39:10.640 So we can use gas pistoning to help explain this behavior 837 00:39:10.640 --> 00:39:13.210 in the lava channel that, for a while during the eruption, 838 00:39:13.210 --> 00:39:15.173 was kind of enigmatic for us. 839 00:39:20.450 --> 00:39:22.350 All right, and then our last question. 840 00:39:23.290 --> 00:39:26.540 Why did the fissure 8 lava delta not collapse? 841 00:39:26.540 --> 00:39:28.120 I've been asked that many times. 842 00:39:28.120 --> 00:39:30.850 I'm not sure we entirely know the answer, 843 00:39:30.850 --> 00:39:33.140 but I'll tell you where my thoughts are on this. 844 00:39:33.140 --> 00:39:34.810 This is something that my colleague, Mike Zoeller, 845 00:39:34.810 --> 00:39:36.360 and I are working on right now. 846 00:39:38.140 --> 00:39:40.941 To refresh your memory about deltas, 847 00:39:40.941 --> 00:39:43.823 we are going to jump back to 61G in 2017. 848 00:39:44.740 --> 00:39:46.700 When a pahoehoe lava delta comes, 849 00:39:46.700 --> 00:39:49.060 it has to dribble over a cliff, 850 00:39:49.060 --> 00:39:51.960 and then find the sea floor and start building itself up. 851 00:39:51.960 --> 00:39:53.380 And it does this, basically, 852 00:39:53.380 --> 00:39:56.440 by putting layer on top of layer on top of layer. 853 00:39:56.440 --> 00:39:58.290 When it interacts with the water, 854 00:39:58.290 --> 00:40:00.540 it makes this fine sediment base, as well. 855 00:40:00.540 --> 00:40:02.780 So, it may have some lava flow in there 856 00:40:02.780 --> 00:40:07.110 and it may be some particles, and a mix thereof. 857 00:40:07.110 --> 00:40:09.363 Whereas up top, it's all lava flows. 858 00:40:10.220 --> 00:40:11.980 As you can imagine, this gets heavy, 859 00:40:11.980 --> 00:40:13.990 and this is not very stable. 860 00:40:13.990 --> 00:40:17.713 So at some point, you develop a zone of weakness. 861 00:40:18.580 --> 00:40:22.200 That manifests itself on the surface, up here, 862 00:40:22.200 --> 00:40:24.340 as cracks in the delta. 863 00:40:24.340 --> 00:40:25.890 Now, just 'cause we see a crack, 864 00:40:25.890 --> 00:40:27.593 we don't know how deep it extends. 865 00:40:29.290 --> 00:40:30.880 All we know is that this land is unstable, 866 00:40:30.880 --> 00:40:34.623 and because it's cracking, it might fail sooner than later. 867 00:40:36.010 --> 00:40:38.720 When it does, it can either fail partially or in whole, 868 00:40:38.720 --> 00:40:41.900 and take some of the previous sea cliff with it. 869 00:40:41.900 --> 00:40:43.720 Either way, when hot water 870 00:40:43.720 --> 00:40:46.580 from the ocean entry interacts with freshly exposed lava, 871 00:40:46.580 --> 00:40:49.680 you get big explosions, and they have hurt 872 00:40:49.680 --> 00:40:51.693 and killed people in Hawaii in the past. 873 00:40:54.080 --> 00:40:55.930 So what's different about 2018? 874 00:40:55.930 --> 00:40:57.080 Why didn't that happen? 875 00:40:58.650 --> 00:40:59.483 Let me back up. 876 00:40:59.483 --> 00:41:02.400 These graphics, I love them, they're wonderful, 877 00:41:02.400 --> 00:41:06.270 but I will note that they are two times height exaggerated. 878 00:41:06.270 --> 00:41:10.540 So, I've redrawn it to be one to one. 879 00:41:10.540 --> 00:41:12.770 And I've drawn this one from Kapoho 880 00:41:12.770 --> 00:41:14.130 to also be one to one, 881 00:41:14.130 --> 00:41:16.430 so that we're comparing apples to apples here. 882 00:41:17.720 --> 00:41:20.450 You'll notice that at the zero marker, 883 00:41:20.450 --> 00:41:22.110 which is where the coastline is, 884 00:41:22.110 --> 00:41:24.620 a pahoehoe delta has a pretty steep drop, 885 00:41:24.620 --> 00:41:26.420 and it has to build itself up 886 00:41:26.420 --> 00:41:29.490 until it reaches a good equilibrium spot. 887 00:41:29.490 --> 00:41:32.023 And it's still over-steepened here, if you notice. 888 00:41:32.910 --> 00:41:35.460 This arrow just implies that the current could erode 889 00:41:35.460 --> 00:41:37.240 some of this more fine-grained sediment 890 00:41:37.240 --> 00:41:39.363 and help undermine the delta. 891 00:41:41.150 --> 00:41:43.060 If we look at the Kapoho Bay 892 00:41:43.060 --> 00:41:45.810 and the first part of the delta that formed there, 893 00:41:45.810 --> 00:41:48.660 it's pretty darn flat. 894 00:41:48.660 --> 00:41:51.090 So I'm not worried about lava that filled 895 00:41:51.090 --> 00:41:54.050 in the bay collapsing, per se. 896 00:41:54.050 --> 00:41:56.420 It's not until it reaches the edge of the shelf 897 00:41:56.420 --> 00:42:01.120 and drops down to deeper levels in the ocean 898 00:42:01.120 --> 00:42:04.120 that it starts to approach this slope. 899 00:42:04.120 --> 00:42:08.070 But even so, on this slope, this lava flow, 900 00:42:08.070 --> 00:42:08.990 even though it's an a'a flow, 901 00:42:08.990 --> 00:42:11.590 is going to behave a little differently than pahoehoe, 902 00:42:11.590 --> 00:42:13.933 which is over-steepened onto this slope. 903 00:42:15.522 --> 00:42:19.830 I think, inherently, pahoehoe might be more inclined 904 00:42:19.830 --> 00:42:22.970 to collapse, as a delta, than a'a flows. 905 00:42:22.970 --> 00:42:25.660 Now this is, we still have more work to do on this 906 00:42:25.660 --> 00:42:29.070 to support this, but we haven't seen any cracks form 907 00:42:29.070 --> 00:42:34.070 in the Kapoho a'a delta, nor did we during the eruption. 908 00:42:34.860 --> 00:42:36.320 Maybe one crack. 909 00:42:36.320 --> 00:42:40.230 But we typically didn't see the features 910 00:42:40.230 --> 00:42:42.950 that we were looking for to say a collapse is coming, 911 00:42:42.950 --> 00:42:45.750 in who knows, days, weeks, months, 912 00:42:45.750 --> 00:42:47.093 but the cracks are there. 913 00:42:48.340 --> 00:42:50.330 The other interesting thing that we noticed, 914 00:42:50.330 --> 00:42:51.163 and I have some pictures 915 00:42:51.163 --> 00:42:52.560 on the next two slides for you guys, 916 00:42:52.560 --> 00:42:57.560 is that right here there's a little bit of breakouts 917 00:42:57.730 --> 00:42:59.860 at the ocean entry that kind of does one 918 00:42:59.860 --> 00:43:00.693 of these pahoehoe things 919 00:43:00.693 --> 00:43:03.640 and it overlaps on top of the a'a. 920 00:43:03.640 --> 00:43:07.130 But in general, the channel will just flow straight 921 00:43:07.130 --> 00:43:08.510 into the ocean. 922 00:43:08.510 --> 00:43:13.093 That told me that it's entering some protected, 923 00:43:15.690 --> 00:43:18.720 self, it's protected its top somehow, 924 00:43:18.720 --> 00:43:21.270 that it's not interacting with the water. 925 00:43:21.270 --> 00:43:22.260 It's not exploding. 926 00:43:22.260 --> 00:43:24.160 It did on a few occasions, 927 00:43:24.160 --> 00:43:26.403 but fairly rare for the whole eruption. 928 00:43:27.328 --> 00:43:31.040 It went out, this is a real bathymetry profile 929 00:43:31.040 --> 00:43:34.100 of pre-eruption and from boats who came by 930 00:43:34.100 --> 00:43:39.100 to do surveying, so it went out two and 1/2 kilometers 931 00:43:39.180 --> 00:43:43.460 away from where the shoreline starts dropping off, 932 00:43:43.460 --> 00:43:46.183 or sorry, from the edge of the old coastline. 933 00:43:47.890 --> 00:43:49.570 So, the thought is, where is all this material going? 934 00:43:49.570 --> 00:43:51.130 And many of us at HVO asked that, 935 00:43:51.130 --> 00:43:52.440 where is all this material going, 936 00:43:52.440 --> 00:43:53.910 and why isn't it exploding 937 00:43:53.910 --> 00:43:56.250 when we know these little tiny things 938 00:43:56.250 --> 00:43:59.890 can cause explosions from pahoehoe deltas? 939 00:43:59.890 --> 00:44:03.520 And so what I realized is that this is actually inflating 940 00:44:03.520 --> 00:44:05.960 and kind of lifting up out of the sea. 941 00:44:05.960 --> 00:44:08.980 It didn't do that all the time, 942 00:44:08.980 --> 00:44:11.470 but the next slide, I'll show you an example 943 00:44:11.470 --> 00:44:13.550 where we did see it lift up. 944 00:44:13.550 --> 00:44:16.913 We saw that twice actually, and it was fairly interesting. 945 00:44:17.820 --> 00:44:21.180 But the point is that this is a cohesive flow 946 00:44:21.180 --> 00:44:23.393 as it extends underwater, 947 00:44:24.230 --> 00:44:27.910 whereas the pahoehoe is just onlapping layers and layers. 948 00:44:27.910 --> 00:44:31.900 So, perhaps this is actually a more stable delta anyways, 949 00:44:31.900 --> 00:44:32.980 even though it already has 950 00:44:32.980 --> 00:44:34.753 a more shallow slope to begin with. 951 00:44:37.330 --> 00:44:38.163 Okay. 952 00:44:39.230 --> 00:44:42.490 This is shortly after the lava entered Kapoho Bay. 953 00:44:42.490 --> 00:44:44.440 We're gonna focus on this feature here, 954 00:44:44.440 --> 00:44:47.263 it's got a peak in the middle and two dips. 955 00:44:48.500 --> 00:44:51.003 We're gonna try to track that through June. 956 00:44:53.010 --> 00:44:53.843 So here we go. 957 00:44:53.843 --> 00:44:55.390 Put a arrow there to help. 958 00:44:55.390 --> 00:44:57.560 It's gonna get more and more subtle as time goes on, 959 00:44:57.560 --> 00:44:58.960 but it's here. 960 00:44:58.960 --> 00:45:01.500 And I want you to focus on this next lobe 961 00:45:01.500 --> 00:45:05.490 that came out and formed a new part of the delta. 962 00:45:05.490 --> 00:45:06.630 We're gonna look at what happens 963 00:45:06.630 --> 00:45:08.180 to the water between these two. 964 00:45:10.300 --> 00:45:12.793 So, in this picture down below, it's here. 965 00:45:15.000 --> 00:45:18.440 Then on June 11th, a few days later, it's here. 966 00:45:19.763 --> 00:45:22.370 On June 14th, it's isolated from the ocean, 967 00:45:22.370 --> 00:45:24.943 and it's actually slightly higher than the ocean. 968 00:45:27.320 --> 00:45:28.510 Then, did I? 969 00:45:28.510 --> 00:45:29.960 Yes, I added the other slide. 970 00:45:31.070 --> 00:45:33.460 June 15th, not much change. 971 00:45:33.460 --> 00:45:35.810 June 22nd, it's evaporating away, 972 00:45:35.810 --> 00:45:39.773 and it is one or two feet above sea level at this point. 973 00:45:42.010 --> 00:45:43.880 That's something that I don't think we've ever seen 974 00:45:43.880 --> 00:45:47.510 in a pahoehoe delta, where it kind of lifts up from the sea, 975 00:45:47.510 --> 00:45:48.930 as opposed to piling on top 976 00:45:48.930 --> 00:45:51.873 and going into the sea and diving down. 977 00:45:52.820 --> 00:45:56.420 And then the last example I have of this is from July, 978 00:45:56.420 --> 00:45:58.060 where we were doing our routine flights. 979 00:45:58.060 --> 00:45:59.410 At this point, we weren't allowed to fly 980 00:45:59.410 --> 00:46:02.230 over the open ocean because there was such a long stretch 981 00:46:02.230 --> 00:46:04.121 where we had no emergency landing 982 00:46:04.121 --> 00:46:05.930 that we just decided it's not worth it. 983 00:46:05.930 --> 00:46:07.510 But this was right on the edge, 984 00:46:07.510 --> 00:46:10.980 and this was the coastline the day before, 985 00:46:10.980 --> 00:46:14.020 and then suddenly this, quote unquote island appeared. 986 00:46:14.020 --> 00:46:16.840 But really, this just kind of rose up, 987 00:46:16.840 --> 00:46:19.570 it's connected to the delta underneath. 988 00:46:19.570 --> 00:46:21.460 There's only a couple feet of water here. 989 00:46:21.460 --> 00:46:23.383 And it's erupting lava. 990 00:46:24.540 --> 00:46:27.210 It's still the fissure 8 lava, has just come down 991 00:46:27.210 --> 00:46:29.480 through the delta underneath and back up. 992 00:46:29.480 --> 00:46:31.050 And so again, we have another example 993 00:46:31.050 --> 00:46:33.880 of something rising up, as opposed to piling 994 00:46:33.880 --> 00:46:35.193 on top and diving down. 995 00:46:36.800 --> 00:46:39.630 So some possible insights from last year 996 00:46:39.630 --> 00:46:41.810 that we're gonna keep working on for this year 997 00:46:41.810 --> 00:46:45.050 is that the submarine slope was shallower in Kapoho 998 00:46:45.050 --> 00:46:49.430 for that delta, and perhaps a'a deltas not only grow 999 00:46:49.430 --> 00:46:54.430 by onlapping, they also grow by inflating their core. 1000 00:46:54.530 --> 00:46:56.490 So, maybe this is more stable. 1001 00:46:56.490 --> 00:46:57.750 There's some more work that needs to be done, 1002 00:46:57.750 --> 00:47:01.250 but that's a potential interesting insight 1003 00:47:01.250 --> 00:47:03.363 into how lava deltas work. 1004 00:47:04.390 --> 00:47:07.920 And with that, oh. (coquis chirping) 1005 00:47:07.920 --> 00:47:10.356 I forgot the coquis were in this video. 1006 00:47:10.356 --> 00:47:11.550 (all laughing) 1007 00:47:11.550 --> 00:47:14.590 I would love to thank you for joining me and HVO tonight. 1008 00:47:14.590 --> 00:47:16.360 We really enjoy serving the community 1009 00:47:16.360 --> 00:47:18.730 and we look forward to doing that in the future. 1010 00:47:18.730 --> 00:47:20.400 Regardless of where our new home is, 1011 00:47:20.400 --> 00:47:21.550 it'll be on this island. 1012 00:47:21.550 --> 00:47:24.180 And we enjoy working with you guys. 1013 00:47:24.180 --> 00:47:25.560 A big thanks to Civil Defense 1014 00:47:25.560 --> 00:47:27.710 and the Puna residents for still welcoming us 1015 00:47:27.710 --> 00:47:31.550 into your communities and letting us take measurements. 1016 00:47:31.550 --> 00:47:34.070 Also thank you to Janet, she does a great job organizing 1017 00:47:34.070 --> 00:47:35.430 all this stuff for us and it's a lot of fun 1018 00:47:35.430 --> 00:47:36.610 for us to give these talks, 1019 00:47:36.610 --> 00:47:40.050 but she's like the unsung hero of all of this stuff. 1020 00:47:40.050 --> 00:47:41.700 So thank you, everybody. 1021 00:47:41.700 --> 00:47:43.230 And I'll take your questions. 1022 00:47:43.230 --> 00:47:46.480 (audience applauding)