Sunday, June 1, 2014

Igneous and sedimentary

This past week, I spent time in two national parks, one in Wyoming (and Idaho and Montana) and the other in Utah.

Last weekend, I went to Yellowstone with my aunt, five cousins (and their families, where applicable), and my grandparents. It was good to spend time with my grandparents, but the antagonism of my cousins was a little too much for this peace-loving guy.

Yellowstone is really the greatest place. I know of no other place with such abundant wildlife. But even better than that, I know of no other place with such active geothermal activity. Yellowstone is a supervolcano situated above a hotspot, where the mantle melts and comes up into the crust as a magma chamber.

When I was on my mission in Spokane, and even some in Lewiston, ID, some people would talk about seeing the ash fall from Mount St. Helens, even though they were on the other side of the state. If Yellowstone were to erupt, it would be really bad. Past eruptions of Yellowstone have deposited 1000 to 2,500 times the amount of ash of Mount St. Helens! If there are indications of it erupting again, I will move to Alaska or Hawaii. I used to think that I'd have to go to South America, but seeing maps of the ash flows makes me think that our youngest states would be safe, and I wouldn't have to adapt to a new culture. Of course, nowhere would be safe, as all that ash in the atmosphere would be wreaking havoc on the climate, but we'd probably survive. Fortunately, there are currently no indications of an impending eruption, and even an eruption in the near future, geologically speaking, could be long after we're gone.

The last major eruption at Yellowstone was 640,000 years ago, but there are all sorts of thermal activity today, as the magma chamber heats the ground and the water in it.

I was pleased with the things I saw in Yellowstone. I always get excited to see basalt columns; they naturally form when the iron-rich (mafic) lava hardens. There are differing rock layers in Yellowstone, but they are all igneous, whether it's basalt columns or ash-flow tuff. 

I think this was the first time I've ever seen bighorn sheep in Yellowstone (my previous visits being in 2006, 2005, 2004, 1996, and 1991 or 92).

Buffalo are always the most abundant wildlife. They get in the road and cause traffic jams. And some clueless new tourists actually stop on shoulders to take their pictures, not knowing they are abundant. That's why I refused to get out the first time everyone stopped.

There are few sedimentary rocks in Yellowstone, but the travertine at Mammoth Hot Springs is probably the most notable exception. Water dissolves the calcium carbonate from limestone (probably buried deep beneath the volcanics), and then it deposits it again when it comes out as a hot spring.

But I was kind of distracted at Mammoth from seeing a bear walk by a herd of elk. (We had earlier driven past a mother bear with three cubs, quite close to the road, but it was impractical to stop.)

We stopped for what we thought was an otter, but upon zooming in I think it was a marmot. Since we were such a big group (thirteen of us, counting the three-year-old and the baby), people saw us and stopped too and caused a traffic jam.

I always like the boiling pools of water, and especially the blooping mud pots. 

 I think this was the first time I had seen a snake there, as well.

Waterfalls are pretty, but you can see those anywhere. I'm amazed at all the volcanic materials.

Later, we saw another bear, and this time we were able to stop to take pictures. I was impressed with my dumb, cheap camera's zoom, even with the pictures as blurry as they are. 

 The bear approached some buffalo. One of them had been lying down but got up when the bear approached. No showdown, though.

It was early in the season, so there was lots of snow, and even some ice on the water.
 

On Memorial Day, our last day, we went to Old Faithful. It's not the biggest geyser, but it's still enormous, and it's amazing how consistent it is. At this point, my camera had died, but that's not too disappointing because 1) it's not much better than my phone and 2) I got a good wallpaper photo for my phone. Geysers provide another example of sedimentary rocks, as the water deposits silica from the volcanic materials when it comes out. I hadn't even heard of siliceous sinter (the deposit) until this trip.

Then it was time to leave the igneous rocks.

On Friday, I left to go to Capitol Reef with my ward. It was actually the first time I've gone camping with a singles ward.

We left about 7:00 p.m., and there were two cars in our group, most people having left earlier. I was in the car behind. About fifteen miles past Richfield, we rounded the corner and saw that the car in front of us had hit a deer; they were pulled off on the side, while the deer lay twitching in road. The deer eventually started lifting its head and gasping in pain. Pretty soon, Trailer Trisha from Wayne County pulled over and went over to get the deer out of the road. She (along with David Jones, our EQP, who was in the victim car) tried to kick it off, but when it wouldn't budge, "Trisha" grabbed it by its legs and dragged it off onto the shoulder of the road. Then she drove off to a place where she could get reception to call the police. Soon, another Wayne County-ite showed up to see if we were fine. Since the deer was clearly in misery, someone asked her if she had a gun. She said, "Not big enough to take down a deer." We found it funny that 1) she had a gun and 2) she knew it wouldn't work on a deer. Pretty soon, Bambi got up and walked away into the bushes. It didn't look very sturdy, though. After the hick women left, the friendly Mormon police officer with the Utah accent showed up. He wasn't concerned about the deer; he was sad it was still alive, because then it could make more deer, but he seemed happy when we said we didn't think it would be able to do that. To make a long story short, the damaged-car group went back to Provo. But those of us in the other car learned about the disdain of the cop toward deer. There were lots of deer next to the road, and one was standing in the middle of the other lane. Having just seen the results of a hit deer, we were paranoid and drove really slow. Some people already at the campsite had contacted the deer group, and then they came out to find us. They found us and led us to the campsite, which was good because we would have undoubtedly missed it, and it was midnight at that point, due to our delays waiting for police and watching for deer.

The next day, I tried to identify the rock formations. Capitol Reef has seventeen geologic formations, whereas Zion National Park only has three. Unfortunately, I wasn't able to recognize them that well, despite Geology 210. But we went on a hike that was undoubtedly Navajo Sandstone.  I think I may have misidentified some Wingate Sandstone as Navajo, but I'm positive our hike was through Navajo.

 We saw a little den of mammals of some kind (notice the one on the bottom sticking its head out). Then we began our hike.

I was impressed to see this little group of Moqui marbles, iron concretions deposited by groundwater, which confirms to me that we were in the Navajo Sandstone, because Wikipedia tells me that's where they occur. My family has some, because at one point they liked to collect rocks, but I never liked rocks as a kid. (I know, right?)
 They have them on Mars, too, where they are known as blueberries. (You can see them in the foreground of this picture.)

What made me sure then that we were in the Navajo was the markings. During part of the Jurassic, Utah was like the Sahara Desert, covered in giant sand dunes. Groundwater came up and solidified the bottoms of the dunes, creating sandstone. On this hike, lots of people asked me about the holes eroded in the rock. I think it was from water dissolving the cement keeping the sandstone together. I was a little annoyed that that was the one question everyone kept asking me, because it was the one I didn't know. When I said I didn't know, the first counselor in my bishopric (who initiated the trip) said, "What kind of geologist are you?" But I'm not a geologist; I'm an editor.

Just as Yellowstone has some sedimentary rocks, Capitol Reef has some igneous rocks. All over the park are these basalt boulders (you expect them to get up and sing something about true love), which came from a volcano 4 to 5 million years ago and then were carried and rounded by a river. 

Later, we walked along a stream to a little waterfall. If I had known how long it was, I don't think I would have continued, as I was barefoot the entire way and I had to walk slow so that I wasn't in too much pain. I was thinking of the term "tenderfoot," which originally meant someone was inexperienced because they had tender feet.

That led me on a tangent in my head about the word literally. Recently, there was a hubbub about literally being used in a figurative sense. Most of the arguments for it were that it has been in dictionaries for a long time in the figurative sense. But something I didn't see anyone observe is that there are varying degrees of literalness. For example, if I said, "I am literally a tenderfoot," the literally could mean several things: 1) I really am inexperienced, and I'm not just casually saying so; 2) I am a Boy Scout of the rank of Tenderfoot; 3) I have tender feet; 4) I am in fact a foot and not an entire body. In each of these examples, I think literally serves a valid purpose. But according to the strictest sense, only the fourth is valid, and that one is nonsensical.

I felt accomplished for having made it all the way to the waterfall and back in my bare feet, even though I literally walked slower than everyone else. Today I could feel where I had stepped on pebbles yesterday. They have parks in Taiwan for that kind of thing, but I will never understand why.

We also saw where Fremont Indians had carved into the desert varnish about 1000 years ago. Desert varnish comes from groundwater absorbing materials and then depositing it again when it comes out of the sandstone. 

Then we drove home. The drive home was much faster, since we didn't have to wait for policeman or watch out for deer.

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