Geology of the National Parks

Video Lecture


Please watch the 34-minute Unit 1 lecture featuring Dr. Richard Alley.

Click for the transcript

Hello, and welcome to Geosciences 10, the Geology of the National Parks. I'm Richard Alley, and with Sridhar Anandakrishnan, my very good colleague, we will be taking you on a tour of some of the most interesting ideas about how the world works and how it affects you, and some of the most interesting and beautiful places on the planet. I think we'll have a lot of fun. I think we'll learn some very interesting things before we get done. And I am looking forward to the tour.

I'd like to start with a little bit of look at our national parks. Just so you know, national parks are an invention of the United States. The first national park was Yellowstone. You see the glorious lower falls of the Yellowstone River here, the coloration of the rocks giving rise to the name of the place.
Of course, Yellowstone is famous for the geysers. There's a giant pot of hot rock down underneath there of melted rock that erupts occasionally and causes big trouble. And between, it heats things and makes it wonderfully beautiful.

This is a geology class, but don't worry too much. We take a fairly broad view of what constitutes geology. We will look at biodiversity. We will look at climate, at living on the planet.

Here you actually see the tracks of a mountain lion walking across the deposits of a hot spring in Yellowstone. Mountain lions often put one foot on top of the other and give interesting looking tracks, and so you can see them there. And here you see the tracks of the bison that are famous in Yellowstone and other places.

Bison came very close to not making it. Yellowstone was important in their survival. Yellowstone was a little island in which no one could shoot them. No one could disrupt their habitat. And so the existence of these owe something to the foresight of the people who said, let us save this piece of the world for the public.

These things are valuable. This is a picture of a hot spring mat that is sitting right below Old Faithful Geyser.

People are prospecting in these, looking for interesting chemicals that will help us. There are biotechnology industries that are founded on things that were discovered in Yellowstone. A bug that has learned to live and do things in really, really hot water has ways of doing things that are useful to us. And so we save this as a beautiful place to go see canyons and geysers, but it's turning out to be a place to save lives and make money as well.

The Park Service has a very interesting difficulty. They have to preserve and protect, they also have to allow us to enjoy things. And sometimes these meet in interesting ways. And so here you see a bison jam. If you go to Yellowstone, you will also see bear jams, and elk jams, and moose jams, and coyote jams. It's the way the world works.

But the bison are beautiful. The Fire Hole River here, behind the bison, was described by the mountain men as flowing so fast it gets hot on the bottom. Well, no, there's hot springs under there. But it's a beautiful place.

Now, I am a geoscientist, a geologist, a glaciologist. I'm one of the luckier people in the world. I get to go to incredibly beautiful places, and people pay me to do things that matter.

I'm a happily married person. I have two wonderful daughters. And you see us here in front of a glacier in Alaska on a trip we took with Penn State at one point.

And I am trained in rocks first, and then in climate and ice and other sorts of things. I studied at Ohio State, and then I finished my studies at Wisconsin, and then I moved to Penn Stat, and been at Penn State since 1988. So I've been around a little bit now at this point.

I have the usual sort of accouterments of someone who hangs around a place like Penn State for a while. I've got a good bicycle. I play a little soccer reasonably badly. I have, as I said, a wonderful family, a nice gardens, an interesting collection of critters. Prancer there is about 22 pounds. He's quite a beast.

But I do. I get to go to great places. These next few pictures are going to be from the world's largest national park. This is Northeastern Greenland.

I study ice sheets, the history of climate that's contained in ice sheets, and whether the ice sheets will fall in the ocean and flood the coasts. And so we get to go to neat places to do this. And so here you can see Korridoren Glacier in East Greenland flowing out from Milne Land towards you, the stripes or rocks that it carries along and dumps into the ocean. And I hope you get the vague idea that this thing might actually be moving.

If you were to go out on that glacier and put markers out, you'd fall in a crevasse, so don't do that. But if you did and came back and surveyed them later, you actually would see that they are moving. If you do you ever get to go to the world's largest national park, the tundra is beautiful in the fall. It's an amazing place to go to.

There are glaciers. There's a huge ice sheet in the middle of Greenland and then little glaciers on the side. Those glaciers are actually shrinking now, as is the big ice sheet.

And if you see these little red lines, the big outer loop there is where the glacier was 100 years ago, and now you can see the glacier has backed up. It is slowly melting away. Why? We'll get there before we're done.

OK, this is the tundra in the fall, a little mushroom and some bearberries there looking at you. The colors do turn. They're very pretty.

This is a fulmar. It's sort of a little albatross. It can stay at sea. It doesn't need to come in for fresh water because it can drink seawater because it has a fancy gland in its nose to exclude the salt. And its flying over the ocean, and the ocean in cold places gets interesting.

The marker there on the white, that's frozen ocean water. That's sea ice, and the ocean really can freeze. And between that and the open water, where that circle is, you can see into the ocean through the sea ice.

It gets warmer. The sea ice tends to melt. The ocean soaks up more heat, and that makes it warmer still. So there's some interesting things we will get to chat about in a little bit.

These are icebergs coming off of Greenland. A glorious fall day, a little fog hanging around up above there, and the sun breaking through. It's just such a great place. It's such a great-- and this is a musk ox.

Musk ox is the same size and shape as a bison, or a minivan. Either is fairly similar. It probably has a better acceleration and cornering than a minivan does. They're actually more related to mountain goats than they are to bison. But this is the Northeast Greenland National Park equivalent of our buffalo or bison here.

OK, in a marker of goodwill, we will see some beautiful things. We will have some fun before we get out of here. My colleague Sridhar and I have had some wonderful opportunities in the way of putting together this course, and you will see some very interesting things that we did, along with Eric Spielvogel from Penn State's e-Education Institute and others.

We had the opportunity to get a really wonderful group of advanced students and then go out and tour some of the national parks with the students carrying cameras. And so you will get to see pictures they took. You will get to see experiences they had as part of our cause, adventure in the great west.

Here's Sridhar in Arches National Park, and these are some of the things that we got to do with the Arches people. We did, indeed, walk through arches. Why are there arches? It will come.

We went to Canyon de Chelly. What happened to the ancestral Puebloans who lived there? We will get to see that before we're done. This is Eric Spielvogel, who put a lot of this together, getting a really good picture for you. And so we got a lot of nice things that came out of this.

We took our crew to the bottom of the Grand Canyon. We hiked down. We had this glorious moonlit night. If you ever get the chance, you got your headlights, so you're not going to fall over the cliff and the fall into the river. And the moon is out. And oh, what an opportunity to go with Stephanie, and Dave, and the rest of the crew, and wander through the depths of the canyon and the glorious moonlight that we saw there.

When you get up in the morning and you're at the bottom of this mile deep hole, and the flowers are blooming, and the hummingbirds are humming by, and it's-- and there's a lot of geology. If you look into this picture, you'll see flat layers, and then you'll see them bend. Why do they bend? This will come. We'll get to that.

Again, we do sneak up on biodiversity whenever we get the chance. And so it's not just the-- most parks were built for geology, but they're increasingly islands of biodiversity in a human- controlled world. And we really do rely on the parks to keep things alive for us.

So more of our happy campers on the way up out of the canyon. It is, indeed, somewhat slower coming out of the canyon than it is going in, a little hotter. We zipped by Glen Canyon. We looked at the lake.

Behind Samir, here, you can see this huge white wall, and then it turns orange at the top. That white was fairly recently flooded. The lake is really low. Why is the lake low? The climate has changed a little bit, and humans are using more of the water.

What does this mean for downstream? What does this mean for the things in the canyon? What does it mean for the Colorado? We will get there before we're finished.

OK, and here's our crew. We're rafting the Colorado below the dam. That dam changed everything on the river. What did it change? We will get to wander through that a little bit and see what it means.

Again, you will see film clips, items, pictures, excitement that our crew generated for you. You'll get to meet them. You'll get to learn from them from Amish and others, here, as we wander through. Here Amish is at Canyonlands, filming something about the river before it gets to the dam.

Here's a crew, really excited. We were down on the slick rock in Canyonlands in the early morning here, waiting for the sunrise to get off and see pretty things. And here's our crew up in Hidden Canyon in Zion. You walk up this cliff, and you hang on to the chain to get around the corners. And that chain is wearing grooves in the rock, and so you will see a little film clip that they made for you when we get that far, and some fun things coming there.

Here are ancestral Puebloan sites, Wupatki, up there with Dave Witmer and Laney and Irene down in Mesa Verde, and then Kim over there filming just outside of Bryce, actually. Stephanie has gone off to work in parks doing some very interesting things now, here with Ranger Jan Stock at Bryce. Here we are looking at a geologic feature. And fairly soon we will get to these.

You look at the picture there above Dave Janesco, and you see that one side is orange, and the other side is black. The orange are rocks from a lake. The black is rocks from a volcano. And that line where they meet is a giant earthquake fault.

What's a giant earthquake fault doing there? Well, Dave is explaining it to you. And you will get to see this before we get finished.

A couple more interesting people in glorious places, very, very glorious places. These are the wild flowers outside of Canyonlands on the drive in. We can show pictures for the whole semester because it's cool. And it's so fun. But we're not allowed to do that.

The university actually believes that you're taking a science course, and the university is typically much more interested that you know something about science than that you focus on a particular science, such as my science, 'cause this is stuff that I really care about. And so we do have to chat a little bit about science. We will actually throw up some facts before we get done. And we will do so.

So I want you to hark back in your memory for a moment to, say, taking the SAT, or the ACT, or the PSATNMSQT, or the CAT, or the-- what, ETC, or whatever you took. OK, hearken back. When I was a student, lo these many years ago, they used to give us questions that involved lists. And they'd-- so you'd be down to about question 243, and they'd say, OK, I'm going to give you a list of things. What would come next in the list?

I think they have gotten rid of these questions, but you may have run into one that's something like this. Here's question 243. What would come next in this list? You got two. You got four.

well, what could come next there? You add 2 to get to 4, maybe you had 2 and you get to 6. That would be a perfectly possible answer.

But no, no, wait a minute. You multiply by 2 to go from 2 to 4, and if you multiply by 2, well, you'd get 8. That would be a perfectly fine answer.

But maybe you multiply 2 by itself to get to 4, and you'd multiply 4 by itself. And that would give you 16. And so you'd sit here and go, hey, this was a lousy question. This is a piece of dookey. OK, get rid of that one.

OK, now suppose that they gave you something that was actually a somewhat better question. So you give you 2, 4, 6, 8. What comes next? Now, that one looks very easy. You say, oh, yes, you're gonna add 2 and you're gonna get 10.

When I was much younger, I played Little League. We were really serious about Little League. And you can't believe it. We'd have lawsuits over Little League. We had coaches yelling at each other. At any rate, I played Little League. It was very interesting undertaking.

And the coaches used to be really big on having us out there doing infield chatter. Now, we were not out there chattering uplifting and morally relevant statements. We weren't saying, batter, do your best for your team and country.

We were out there saying, hey, batter, your shoes untied. Hey, batter, you're ugly. Hey batter, hey batter, hey batter, swing! Two, four, six, eight, the batter's got a bellyache.

OK, so it could have been 10. We would never out there go 2, 4, 6, 8, 10, 12 in the Little League. We were out there saying, 2, 4, 6, 8, the batter's got a bellyache.

Now, this actually might be relevant to something. If you were sitting there saying, two, four, six, what comes next-- eight-- you get it right. And you sit there and two, four, six, eight, what comes next? And you say 10, you get it right. You say, I know what's going on.

But if you're out there playing Little League and you're saying 2, 4, 6, 8, 10, you got it wrong. Your ability to see two, four, six and fill in eight doesn't prove that you know what's going on, because if you thought you were taking the SAT and you're really playing Little League, you got eight right, but you got the next one wrong. You're sitting there, 2, 4, 6, 8, 10, 12.

And the batter-- that might have worked, actually. The batter looks at you, says what's wrong with you? And the pitch goes right by. But that is not the way one does it.

OK, this does feed back into science. This is relevant to science. And let's look at how this works. What is science?

It's humans. It's humans doing human activity. There is no crank that you turn that spits out knowledge.

Science is done by humans. They are humans who have foibles and failings. They are humans who have mistakes. They cheat, and lie, and steal. They have mating rituals. They're just like everybody else.

But science has a very loose set of rules that allows it to do better at some things than other human activities. It's very limited. It does certain things well, and it doesn't do other things at all. But the things that it does, it actually works on.

So what is science? The first thing in science that you do is you find something interesting. You gotta care about it. It has to matter, people. You go out and look at things and you find something interesting. OK, this is cool. I could learn about this.

What you then do is ask, what do we know about this something? There are many people in the world. There have been many people in the world. Your ancestors were smart. Lots of people around the world in lots of places were smart. You will never in your life reinvent everything they did.

So first of all, you go and find out what they did. You could call this research. You could call this going to library. You can go and talk to people. There's other ways to do it. But if you're interested in something, you're really stupid if you don't find out what other people knew. They may have your answer for you already.

OK, so you find out what's known. Then you say, OK, they were really bright people. They did really good things. But they were human.

They might not have put together everything. They might not have had the ideas that I have. I, as a new human standing on their shoulders looking out, may be able to improve things.

So you take what you know and you say, how can I move forward? How can I go beyond them? Where can I get a new idea?

This is the fun stuff. No one has any idea where new ideas come from. It may come from dreams. It may come from traditional knowledge. It may come from brainstorming.

I take hot baths. I get really good ideas while taking hot baths. I don't know why, but it works.

OK, so you look for a new idea. You get a new idea. And then, you can't stop. If you just stop, there's some other human activities. You got new idea. You write your novel and you're there.

But in science, you actually have to ask, is my new idea really a step forward? Have I gotten somewhere that those people before me did not get? And so you actually have to go test your new idea, and you have to test your new idea against nature, against the real world. You have to see if your new idea is better than what other people had done.

And the way this is done-- and this is a very, very strict rule in science, and this is what sets science apart from other human activities-- you have to find a situation in which you predict something, and the old ideas predict something else. If you always agree, then you have just found a new way to restate the old idea. You actually have to find a place where you say, tomorrow, the sky will be purple, and the other one says no, it will be blue, where you say, if I do this, that will happen, and the other idea says no, if you do this, the other thing will happen.

You find a way that they differ, that you make different predictions. And you have to predict it. You're not allowed to just explain it. You have to predict what's going to happen. Then you set up the situation. You see what happens.

you can call this making hypotheses and doing experiments. There's lots of terms that you probably learned in fifth grade. This is a list of terms of the scientific method. But this is really the scientific method.

Get interested. Learn. Get a new idea. Test it. But you have to test it by making predictions, and then you have to say see what happens.

If your idea repeatedly fails-- one time, yeah, nature might be fooling you, there's lots of things can go wrong in an experiment-- your new idea just keeps-- pff, it fails. Pff. It fails. Pff. It fails. OK, throw it away. You were wrong.

Even if you loved it, even if you desperately thought it was a beautiful idea, if it fails, you gotta throw it away. You're wrong. If it succeeds-- OK-- if it succeeds, are you right?

And this is the point where we go back to playing Little League and two, four, six, eight. If your idea succeeds, you make the prediction correctly over, and over, and over again, it is possible that it is true. You have Truth with a capital T. You've nailed it. It's there. There's choir singing, and everybody's giving you-- you might have it right.

You might have been close. Isaac Newton came up with rules of physics. Isaac Newton is really, really accurate for a lot of things. Scientists started to say, well, Newton is truth. We're done. All we have to do is estimate things better. Newton's got it nailed.

We still teach Newton in physics because it's still very useful. But Newton-- if you go to really big things, you got to really small things, you go to really fast things, Newton is wrong, and you need Einstein, and you need quantum, and so on. Now, really big is a solar system or a galaxy, and really small is an atom, and really fast is 90% of the speed of light.

So Newton's really good for the world we live in today. When people build buildings, they don't actually worry too much about quantum. They use Newton's laws. But Newton is not right. He's not true in any way, shape, or form. He was just close. He's useful.

The other option, of course, is that you got it right, but you were just lucky. And this is where you're sitting there and saying, two, four, six, what comes next, eight. And you say, 2, 4, 6, 8, what comes next, 10, and you're playing Little League. You got eight right because you were lucky, not because you knew what was going on.

And so there's three options. If you make your predictions right, you may be true. You may be close. You may be lucky. No one ever actually tells you, you are now playing Little League. Nor do they tell you, you are now taking the SAT in the real world.

And so you never will know. So science is not really about Truth with a capital T. In fact, if there's one thing that we do know that comes very close to Truth with a capital T, it's that eventually, as a professor, the students always show us up. The students learn something we don't know. The students find some mistake that we made. And so the experience of every professor in history is to watch students go blazing by at full speed, which in turn says that the professors did not know everything, and there was not Truth with any capital T.

And so science is not really Truth with a capital T. What science is is building. Our ideas will we be revised.

It's getting better. It's getting closer to being really good, to having it really right, and keeping on doing this. Get a new idea. Test it.

If it's better than the old one, keep it. Get a new idea. Test it. If it's better than the old one, keep it. Accumulate the knowledge. Accumulate the wisdom of the brightest people in the world over generation after generation, always testing it against nature to make sure that it works, and pull this together.

Now, we will all occasionally trip over some questions that are very interesting to people. There are people who say, look. The world is no older than Britain history. I have a sacred book, and the story in this goes back 6,000 years and that's it. And I know this. This is revealed truth.

And the scientists said, well, no, it doesn't look that way. I have counted more tree rings than that, and we know trees put down annual layers. So we will come to interesting questions like this.

We will come to questions of evolution and other sorts of things. And when we do, we should chat about them a little more. These are things that matter to people.

They're things that matter in politics. They stir up a lot of fervor and fever on many sides, and it's not just both sides. There's all sorts of interesting ideas floating around out there.

When we get there, just remember what science is. It's subject to revision. It is not Truth with a capital T. What it is, though, and I think that everybody knows this-- if we pretend that science is true, we are successful.

I did not die in second grade of a really virulent fever because somebody had antibiotics that were generated by science. I walked in this building and I did not worry that this huge open space, with these heavy things over my head, that it was going to come crashing down on me and kill me. I'm speaking to you through the wonders of a cup of sand, a cup of oil, a little bit of red rock, and an amazing amount of intelligence in science that turned them into computers, and fiber optics, and other sorts of things, so that we can actually chat this way.

If you were to get lots of different groups of people around-- get the volleyball team, and the knitting circle, and the bridge club, and whatever else-- get a whole bunch of different groups of people, and give each group a cup of the right red rocks, a cup of sand, a cup of oil, and say, turn this into a computer communication system. Science and engineering have done this. And I am reasonably confident that the volleyball team and the knitting circle will not succeed in doing so. Science works, and it works really, really, really well.

It works. It works. It works-- there just isn't much doubt about this-- if you [UNINTELLIGIBLE] it to engineers.

Once you have the idea, you gotta turn into reality. You've gotta make it work. And then you need business people to sell it, and what have you.

But science really, really does work. It's out there. It's one of the great things of humanity.

It's one of the things that allows us to get new ideas. It allows us to share information. It allows us to communicate.

Now, I would like, briefly, to just tiptoe around some other ideas that you would probably get in different classes to a greater extent. We're coming to you as a communication medium. We're coming to you over the internet. We're chatting about way things are.

The internet has changed a lot of things. We can sit at home and we can Google each other, and we can find out what's going on. And that's very fun.

It has changed information. If you go out and look on the web at certain things that we will talk about in class, evolution, climate change, age of the Earth, what have you, you will find an incredible spectrum of views out there, some of which are based on this vast pyramid of knowledge that's been put together by humans, in the scientific method, over thousands of years, and some of which are based on somebody sitting down in front of a computer and a blog and typing what they think. And you pull them up on the search engine, and they'll all pull up as being equal.

They just show up. There's no sorter in there. And so why should you believe my communication, that's a scientific communication, and not the blogs that you will find that say, oh, he's an evil liar. He's trying to corrupt your poor minds.

And so I presume the great majority of you actually have a pretty good understanding of this, but it's worth just a word or two to chat about that. There are so many different sources of information. You could go to an internet. You can go to magazines. You can go to books. You can go to the scientific literature.

And you know where I'm going. The scientific literature is the one I want you to lodge in your brain for a little bit. There is a great difference in some of these communications between a blog, which may have nothing behind it but the informed or uninformed opinions of one person, and a scientific result that we're going to try to present here in class, which has, sitting behind it, this pyramid of knowledge, of testing against nature by thousands and thousands and thousands of people in all the countries of the world over all of recorded history, that's very carefully put together to see if it works.

You go, look, and say, OK on the internet side, in the blogs, there's some great stuff out there. But there's a lot of garbage out there, too. There's just dookey knee deep or higher. And as you go from the internet through these other things, what you find is you get to typically better quality information, not always, not everywhere, but typically better quality than internet.

The internet so cheap, and so easy, you don't have to be in it for the long haul. There's a huge amount of it that is not carefully examined to see whether it's even vaguely true or not. Whereas, if you get on the other end out there in the scientific literature, we jump through incredible hoops to try to make sure that it is basically correct.

If I wanted to tell you that my new idea works, I have to, first of all, get the new idea. Then I have to test it. Then I have to do all this stuff and see if it works. And then I have to write it up.

I have to say, this is what I did. And you have to be able to know exactly what I did. You have to be able to duplicate what I did.

Put it out there. Tell the truth, what I did, what other people did. And then I send it in and I say, please, please publish this over the world.

And they say, well, no, not yet. We're going to get a couple world experts, and they're going to look at this really carefully. And they're gonna make sure that you're not lying, or cheating, or stealing, that you have acknowledged the knowledge that you pulled in from other people, that you've told us what you did, that your results look good, that you have run careful tests, that your statistics are not cheating.

And they're gonna run a whole bunch of different things. And they'll get these world experts to look over it. And only after the world experts have said, yeah, that makes sense am I allowed to put it out there.

And this still does it make it true. Don't for a minute think that it does. But it means that a whole lot of the dookey is missing. And if it matters, the scientific literature is the place you go to look.

It may not be friendly. It hasn't been distilled down. In this course, we will try to distill the scientific literature into something that's useful, but no world experts are actually vetting the last word I just said to make sure it was the right word.

It is slow. It is careful. It's not the fastest way to get there. There are things that-- you'd say, can't you get that out faster? This is such a cool idea. I really want it.

Now, we have to be careful. We have to follow the rules. When people read the scientific literature, they should know that it is standing on this pyramid of knowledge that comes up from the depths of antiquity and the care of all these people across the planet.

And so that's just a little bit of where we're going, what we're doing. We will get much more down to specifics. We will talk about rocks, and we'll talk about rivers, and we'll talk about glaciers, and all sorts of fun things.

But in the end, keep in mind what it is. It is humans doing really important things to keep humans happy, healthy, and terrific, fed, and cured, and clothed, and housed, and healthy and wealthy enough that we can actually worry about big questions of what we're doing here and what we should be doing here. Science doesn't really tell us those. But it does give us the wherewithal to address those.

And we are going to address those, some subset of them. How do we humans stay happy, healthy, and terrific on the planet? How do we keep from being killed by giant waves, and volcanoes, and earthquakes, and what have you?

How do we find valuable things? How do we track down keeping things alive? And we're going to do that by going to some of the really beautiful places on the planet with some really good people who worked hard to show it to you and having a lot of fun. I personally look forward to the trip, and I hope you do too. Thank you.

Want another look?

Check out the Unit 1 PowerPoint Presentation used in the online lecture here.