To begin with I would like to quote the first paragraph of an abstract submitted on September 7 1954 by Donald E White to the Geological Society of America:
"During the night of March 1 and 2, 1951, an inconspicuous group of hot springs and small mud volcanoes in northeastern California burst into spectacular eruption, unequaled by other known mud volcanoes. The eruption cloud of steam, gasses, and mud particles rose several thousand feet in the air and distributed fine debris to the southeast for a distance of at least 4 miles. More than 20 acres of the hot-spring area was intensely disturb and greatly modified by the eruption estimated to involve at least 6 million cubic feet or 300,000 tons of mud. Several days after the eruption, the area was barely active."
Some further quotes from an article from the University of Utah says this about it:
"At the time of the mud eruptions, local residents heard loud noises and felt a series of tremors, similar to those felt during an earthquake. . . By noon on 2 March 1951, the thermal activity consisted of boiling mud pots with clots of mud occasionally thrown 10-20 feet high. . . Although no previous violent eruptions at the Lake City hot springs were recorded, aerial photos taken in September 1946 show several cones of mud volcanoes, which indicate past activity."
The difference between a "volcanic" eruption and a mud volcano is that the former is directly from magma forming new volcanic rocks. A mud volcano on the other hand, is only related to a sudden release of energy stored in hydrothermal systems near the surface, consisting of fine mud sediments at surface levels. While the two kinds of eruptions are distinct one can sometimes have an effect on, or even trigger the other.
It appears that the reason for the geothermal activity in the Surprise Valley is related to the uplift of the Warner mountain range. The fracturing of the bedrock caused by the uplift has opened the way for surface water to find its way down into the heated regions of the earth. (In this area the hot regions are at a relatively shallow depth) The water then percolates (like in a coffee pot) back to the surface where it manifests itself as a steam vent or hot spring.
The area of the mud volcano at ground zero is associated with a nearly two mile long zone, running north to south, overlaying bedrock fractures as deep as 4500 - 5000 feet below the surface. Within a 1.5 mile area of the zone there are approximately 100 hot spring orifices making it the most prominent and largest hot spring feature in the valley. If you visit the area in the winter just after the snow falls you will notice the snow melt pattern that indicates the heated area.
Since 1951 there have been about 20 test wells drilled around the mud volcano area. In the early 70's I remember the newspapers reporting that there was an explosion of one of the drill sites in which the eruption tipped the drill rig over and burned a man working on the project. Mud was blown over two miles into the little community of Lake City to the south.
References:
Article "Overview of the Lake City California Geothermal System" by the University of Nevada, Reno
Article "Geothermal Activity in Surprise Valley" University of Utah Research Institute Earth Science Lab
To get the most out of this Earth Cache you can or must visit the following path.
Step One: This is not a must but I highly recommend that you visit the Surprise Valley Hot Springs at these waypoint coordinates. N 41 31.981 W 120 04.678. Please keep in mind that this water is extremely hot, usually between 205-208 degrees. Keep an eye on your children and pets. Don't touch the water! Believe me it's HOT! This is the most dramatic hot spring in the valley. While standing at the coordinates look south of you between the two buildings and you will see another well to the right just like the one at the coordinates. The large Quonset building behind the main lodge at one time housed a large hot water swimming pool. It's been filled in. Many of us local residents remember swimming there. Did you ever swim there? Keep in mind this water has been boiling up like this for as long as we have record. In May of 2013 NASA was at this very location doing some research regarding geo thermal power generation. Also the University of California has been surveying the valley with slow flying drones to get a magnetic image of the geological features of the area for the purposes of understanding the underground geothermal attributes. If you want to EXPERIENCE the hot water spend a night or two in the motel there. Each room has a small cement tub in the back with fresh running hot water (cooled down a bit) for your enjoyment. It is well worth it I've done it a couple of times.
Step Two: A must. When you leave the Surprise Valley Hot Springs take a right on highway 299 headed east until you come to county road 18 and turn left. Go to the Parking Coordinates N. 41 35.858 W 120 05.127. Across the road to the north is where the next waypoint coordinates (N 41 36.083 W 120 05.121) will take you. Just walk north alongside the fence. You will be on public land so don't worry about trespassing. It's about a quarter mile easy hike to the head of the springs. See if you can count how many different orifices there are where water is coming out. Notice the plants growing in and out of the water? What are the colors you see? Again watch your children and keep your pets on a leash. While the water here is not as hot as what you just saw at the motel it is still hot! Notice the bones of a recent cow that got stuck in there and met her end. I have heard stories of dogs jumping in this hot water and meeting their end as well. Keep them on a leash! Archaeologists have studied this area and it has been discovered that the area around and mostly west of this spring was an ancient Indian settlement. There is actually an ancient human skeleton that was found and is buried on the other side of the fence somewhere.
Step Three: This is not a must but I think you will find it interesting. Follow the waypoint coordinates N 41 35.900 W 120 05.527 to the Leonard's Hot Baths. It's just a stone's throw. You will notice a white gate on your left. While this is private property we have received permission to enter. Just park safely by the road, open the gate and walk to your destination. On your walk you will see another hot spring to your right not far from the gate. BE CAREFUL!!! When you get to the coordinates you will see an old cement swimming pool. That pool was fed by the hot water in the area. I remember swimming in that pool as a kid but it hasn't been used for quite a while. If you want to thank the property owner for allowing you access you can e-mail Janna at montanajanna@gmail.com. She hopes to someday make this a place where people can come by and enjoy the water for free so please be respectful to her property.
Step Four: This is a must. Put in the coordinates for the Applegate Hot Spring, N 41 36.944 W 120 06.215. Continue west on road 18 till you come to the first well graveled road to your right and take it and follow the coordinates. At about the second dirt road that turns to the right go up the hill. Don't turn off too soon. If you think you're car can't make it it's just a short walk. Once there notice the difference in the setting and the flora around this spring. Are there plants growing in the water? Does this water appear to be hotter than the last spring you were at? Why would you think that? Don't miss the little monument to the Applegate Trail nearby. Read the monument because I will be asking you to send me one of the interesting things that the pioneers noted about the area. (Someone local needs to put a geocache in this area. I see a great spot.)
Step 5: You should have your coordinates in for Ground Zero and the Mud Volcano. Drive back out to road 18 and continue heading west. When you get to Highway 1 or Surprise Valley Road turn right. Follow the road to the coordinates. When you get to ground zero you should be standing up high off the road near a fence. As you look out to the east about a half a mile, you will be looking over the site of the mud volcano. Can you recognize it? What makes you think you're seeing it? How does that area look different than the surrounding land? Look to the southeast and gage how far four miles away is. Imagine an eruption in the volcano area that threw debris four miles to the south east. Imagine steam and gasses flowing several thousand feet into the air. Would you have wanted to be standing where you are right now when it erupted? If you drive just a few hundred feet south from Ground Zero on the highway you can see a broader but lower view of the mud volcano area. Please do not go over the fence into the private property area.
To log this cache please provide answers through the e-mail address on my profile page, to numbers 1, 2 and 3 below: (Please do not post your answers on the cache page or I will have to delete it.)
#1 Please tell me what the people who traveled the Applegate Trail noticed about this valley that is relevant to our subject.(You might want to be sure and get this while you are there.)
#2 As you look over the mud volcano area what geological characteristics do you see that would indicate that you are looking at a catastrophic, volcanic, geothermal area?
#3 What are one or two differences between the mud volcano area and the surrounding area? You may notice different things depending on the time of year you are there.
Photos are not a requirement to log this cache but pictures of your journey are appreciated if you can post one. All photos of the actual mud volcano area or other logging requirements will be deleted.