WEBVTT 00:00:05.000 --> 00:00:06.000 First, think of the ground surface, 00:00:06.000 --> 00:00:11.000 and then let's start having a mass of very hot molten rock, 00:00:11.000 --> 00:00:12.000 which we call magma, 00:00:12.000 --> 00:00:14.000 moving up towards the surface. 00:00:14.000 --> 00:00:19.000 As it moves up, it starts to break the overlying rock. 00:00:19.000 --> 00:00:22.000 And those breaks basically are earthquakes. 00:00:22.000 --> 00:00:25.000 So in the area, on the ground surface, 00:00:25.000 --> 00:00:28.000 above the molten rock, which is moving up, 00:00:28.000 --> 00:00:30.000 there will be hundreds to thousands 00:00:30.000 --> 00:00:32.000 of earthquakes per day. 00:00:32.000 --> 00:00:35.000 And those earthquakes will probably be in the 4.5 00:00:35.000 --> 00:00:37.000 magnitude range or larger. 00:00:37.000 --> 00:00:39.000 The other thing that occurs 00:00:39.000 --> 00:00:41.000 as this gets close to the surface, 00:00:41.000 --> 00:00:43.000 the ground starts to deform. 00:00:43.000 --> 00:00:44.000 It actually gets bent. 00:00:44.000 --> 00:00:48.000 So in the area of the earthquakes, 00:00:48.000 --> 00:00:51.000 you should also see significant ground deformation. 00:00:51.000 --> 00:00:57.000 Sometimes up to a yard a year may occur 00:00:57.000 --> 00:00:59.000 preceding an eruption. 00:00:59.000 --> 00:01:01.000 Also, we would expect to see changes 00:01:01.000 --> 00:01:03.000 in the hot water features, 00:01:03.000 --> 00:01:05.000 the geysers and hot springs, 00:01:05.000 --> 00:01:08.000 as this molten rock gets near the surface. 00:01:08.000 --> 00:01:10.000 And we would expect to see changes 00:01:10.000 --> 00:01:14.000 in the geothermal gases that come from the ground. 00:01:14.181 --> 00:01:19.000 Now, do we have earthquake swarms in the park? 00:01:19.000 --> 00:01:20.000 Definitely. 00:01:20.000 --> 00:01:22.000 Do we have ground deformation? 00:01:22.000 --> 00:01:23.000 Definitely. 00:01:23.000 --> 00:01:25.000 Does the hydrothermal system change? 00:01:25.000 --> 00:01:26.000 Every day. 00:01:26.000 --> 00:01:29.000 But are those signs of an impending eruption? 00:01:29.000 --> 00:01:29.000 No. 00:01:30.000 --> 00:01:34.000 All these things have to be coincident, in the same area, 00:01:34.000 --> 00:01:38.000 and very concentrated, at greater magnitude, 00:01:38.000 --> 00:01:42.000 and many more of them than we currently see. 00:01:42.000 --> 00:01:44.000 So having an earthquake swarm near Norris 00:01:44.000 --> 00:01:48.000 and ground deformation in the White Lake area, 00:01:48.000 --> 00:01:51.000 and changes in the thermal system in Mammoth, 00:01:51.000 --> 00:01:55.000 they're all part of the normal vital signs of this volcano. 00:01:55.000 --> 00:01:58.000 And there has been nothing that has been indicated 00:01:58.000 --> 00:02:01.000 that there is an impending eruption.