Grand Canyon Geology Talk by Louis Schellbach (1955)
Transcript
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Now, I might begin by telling you that we believe you came to enjoy yourselves and not to be educated. But we do believe that if you know what you are looking at, you will enjoy yourself just that much more. So this station then, is a government operated station built by the National Park Service primarily for your benefit.
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Now, you come to Grand Canyon. You do not have much time. You do, of course, appreciate its rock sculpture and its color out there, but really, there is a lot more behind that canyon than just its rock sculpture and its color. So this station then has been built as a mechanism for you to use to interpret what you see out there.
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Now, on the parapet here is this battery of high powered binoculars. Now, each and every one is fixed and fastened upon a particular spot in the canyon that has a story to tell. You cannot move these telescopes. And then beneath each telescope is a small exhibit box in which there are specimens that have been brought up from the spot on which the telescope is focused, so that you can see them close at hand.
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In other words, saving you the time of walking down there. However, should you doubt any of the specimens in the cases here or inside, I'll tell you. You can reach any of those spots by trail, down below, and see the story in the rocks yourselves. However though, we fellows will tell you that the Bright Angel Trail from the rim to the river is only seven miles long.
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To be accurate seven and 8/10 miles. Yet in the same breath, we will warn you that should you go down there, under your own power, turn about and climb out. Oh, you will swear it's 77 miles back. (laughter) You try it sometime. Now, you do not look through these telescopes with the thought of getting a wonderful view. No, they are not there for that purpose.
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They are there to act as pointers, to point out the spot in the canyon.
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Now, the object is to look at that spot through the telescope. See the place in nature. See its relation to the rest of the formations. Then look at the specimens in the box. Read the labels. Put two and two together as you go along this parapet. And by the time you've reached number 15 Telescope, you should have a good comprehensive idea of what that canyon stands for.
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For they are the facts. You hook the facts together. Now, I took over 75 years of scientific research to wrest these stories from the rocks of Grand Canyon. Place it up there in that manner, so that you can get it in 20 minutes. If you will think on what you see. In other words, we want you to have the joy of discovering for yourselves.
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We point out the fact, you reason on it. However, though once a day this time of the year, the man on duty here has to hook up these telescopes for you, to give you a Grand Canyon story. And today, of course, that duty happens to be mine, as well as my pleasure. But I always maintain that despite the long years of experience.
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And I've been here over 22 years, and I happen to be park naturalist too, that despite those long years of experience, for me to give you a Grand Canyon story in the short time and allotted, seems a tremendous task. Oh, it's a terrific story, to try to compress it, into the short time they expect us to give it.
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We have, however, broken it down into four main phases, so that we might present it easily, and so that you might grasp it easily. Now, the first phase answers your question; what happened? Did the earth crack open? Did glaciers cut it? What made that terrific gorge out there? The second great phase is Earth's history and Earth's building, as exposed to view in those canyon walls.
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The third great phase is the record of life, through the ages, as found in the form of fossils in the canyon formations. And the fourth great phase is the canyon today, now, as it influences living things. Now you people keep those four main phases in mind as we progress, see? Number one, then, what made it? Number one telescope
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there points to the river three miles away from you in an airline. And of course, you are not a bit impressed with the river. No, I don't blame you. It looks like a muddy, insignificant little creek down there, doesn't it? But, oh, how you are fooled. You're seeing that river three miles away. And at that particular spot, the river is over 300 ft wide.
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And you know how long a city block is. And it's low water now, too. By the way; she will cover those white banks down there when the floods come down. And that little creek down there happens to be one of the world's most dangerous rivers. Now, no fooling. You see, other rivers have been servants to man. Highways of commerce, trade, communication.
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But not to the Colorado River. Now, what happens to be the second longest river in the United States? It is over 2000 miles in length. And that little creek down there has one dangerous rapid for every day in the year. Now, that's 365 cataloged dangerous rapids. Oh, she has a lot more than that. But those are the dangerous ones.
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And that little creek down there cuts 26 distinct canyons. 26 of them. 19 of which are major canyons. While Grand Canyon out here, of course, is the largest and the most spectacular of them all. The final major canyon it passes through on its way to the Gulf of California is Black Canyon. And in Black Canyon today is located Hoover Dam.
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And from up here, three miles away, you can see the river is muddy. Oh, it's very, very muddy. So muddy, in fact, that we fellows say, "it's too thick to drink and too thin to plow." And that's literally true. For listen, by any point in this canyon, and this canyon is 217 miles long, one canyon, by any point in it
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that river is carrying an average of a half a million tons of earth every 24 hours. Now, can you people grasp a half a million tons? Think of it in terms of five ton trucks, and you might get an idea of how muddy that river is. Now that, of course, happens to be just the average flow. Well, she carries much more than that in times of flood.
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The record was September 13th, 1927, when one flood came through that canyon, and when that river carried 27,600,000 tons. By any point in the canyon, in 24 hours time. Now that's more than a million tons an hour. Literally moving land. You see, that river is growing through this canyon at a speed of from two and a half to 12 miles an hour, depending on the flood waters.
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It has a drop of nine feet to the mile, and this canyon is 217 miles long. And because of that speed, the river cannot drop that load in this canyon. Oh, it must carry it outward. And only, of course when the river reached sea level at the Gulf of California, there the river slowed up, and there it was able to drop its burden,
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and there it dropped It. There it built its delta many, many miles an extent and many thousands of feet deep. There that river, by the way, was building rock formations for the future, just as some of the rock formations out there, in the canyon walls, was built in the past by ancient muddy rivers. Now, I've just given you the explanation of the river because in my estimation, that is vitally, vitally important.
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Oh, you must know something about that river, because that river cut this canyon. Now, how might I explain it to you briefly, un-technically and without hair splitting? Oh, I might attempt it in this manner. There are five great eras in Earth's history. Only five. No need for me becoming scientific, is there? And telling you they are
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the Archaeozoic, Proterozoic, Paleozoic. Mesozoic and Cenozoic, see? Those are just scientific names. Now you people think of them as five chapters in Earth's history. In other words, the history of the Earth written in five chapters. We are living in the fifth chapter. It is the present, still going on. Now visualize this; sometime after the close of the fourth chapter, the Mesozoic,
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the land in this entire region out here, was comparatively low above sea level, not as high as it is now. And through that low land there meandered a lazy, slow, sluggish, dying, moving river on its way to the sea. Now that was the Colorado River, and geologists tell us this is a young canyon out here, a young canyon just several million years old.
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Oh, that's young, before I'm through, you'll be surprised. And then the land in this region slowly started to rise to dome-up, oh, so slowly. You just couldn't measure it. Any human being's lifetime. In fact, it may still be rising right here. But we don't live long enough to measure that rise and that slow rising of the land enabled the river to maintain its original course.
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You see, if the land would have come up quickly, it would have blocked that river out there, and the river would have had to flow around the base of this gigantic dome, which is Grand Canyon, or it will look flat to you out there, I know. But it isn't. You must come uphill from, no matter what direction, to come to Grand Canyon.
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Well, now the river and the canyon is not doing that. Cutting and flowing around the base of the dome. It is part way up and around the dome, proving the slow rising of the land. And as the land came upward, it did something else, it gave speed to that lazy river. And speed, of course spells power. Now, the material that that river was given to carry in the form of sand, silt, gravel, boulders, they became the tools that that power used.
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And as the land came upward, the river ground and pounded and abraded and scoured and cut down through it faster, as it hit the softer layers of rock; slower as it hit the harder, until out there today, she is a mile below the rims. But don't lose sight of the fact I told you this started after the close of the fourth chapter of earth's history.
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You now are working on the completion of the third chapter. The fourth was once above our heads. Here almost again as high as that canyon is deep. Hence that river has cut through almost two miles of Earth's crust, exposing to view, all of Earth's history in this region. For the river down below there, is cutting through ancient black rocks.
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All the oldest rocks known to man. Wherever they are found on the face of the earth, they are number one. Number one in the scheme of things out there, no rocks any older beneath those rocks, in the bottom of this canyon where they go down, down to the magma layer, the molten rock layer upon which the Earth's crust rests.
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So you see, then, as you people stand here and look out with just a little bit of inspiration, you suddenly begin to realize that you are doing more, oh, much more than just looking. You're looking back through the ages. Now that's how the river cut the canyon. But at no time was that river as wide as from this rim to that north rim over there, ten miles away.
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No, the river probably was not much wider than it is today. It cut a narrow and straight canyon downward. But other forces are at work, eating away the canyon walls on the sides. Gravitation pulls down the loose particles, the trees growing along the edges of the cliffs, out here, their roots get into cracks of rocks, pry off pieces down they fall. Water getting into the cracks of rock in the wintertime and freezing.
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Now, you people know what freezing water will do. Cliffs snap off and down they fall. Now eventually they get into the river in one form or another. And that river flowing so fast through this canyon cannot drop that load here. Oh, one 20 minute rainfall in this region will remove more land than an entire season's rainfall in a more vegetated region.
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You notice out there afterwards the plants do not grow close together. Land wears away very, very rapidly here. That's what is widening Grand Canyon. And number two telescope. They're pointing to bent and twisted rock. Proof of land movements. Mother nature, in the beginning, puts the rock layers down horizontal: sea bottoms, lake bottoms, river deltas. Windblown sands. Stress and strains in the Earth's crust.
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break them. Slipped them by each other. See that point over there? Hopi Point is 180 ft higher than this point, where the Earth's crust snapped and slipped 180 ft, right straight across Grand Canyon, making that side canyon over there. Oh, notice that white band or cliff below the rim opposite you over there. Now keep your eyes on that white band.
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Now follow it to your right. Way at the head of that side canyon over there, where the rim is higher on the left then on the right. Right opposite you, drop below the rim to the white band, right where the snow is. Notice the white bands that way, instead of being that way, it's that way. Making the famous Bright Angel Fault.
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Or these movements will bend the rock layers or it will over thrust them, or it will break the Earth's crust into blobs, and it will tilt the blacks up into mountain ranges. So when you see rock layers tilted or bent, you know there's been crustal movement at that place. However, though, to you know, since I've been on the job here, I found that that's mighty hard for most people to believe that land moves.
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The Spaniard, you know, called it Terra Firma Farm land. You and I think of everlasting rocks and everlasting mountains. And there is no such thing as mountain ranges where a way to complete level plains, rocks disintegrate into sands and silts and gravels and mud are redeposited recently defied re thrust up into mountain ranges again to be again re worn down.
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And as I always say in my later moments, the land she do move, she do that just because we don't see it move in our own lifetime. We don't believe it moves, you see. But if you live in an earthquake country, you know she moves up. Nobody in California today.
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Actually get a rise out of people from California, especially the fellows from Berkeley in they say, oh, California. We don't call them right quakes. We call them adjustments there. And.
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I have to make people laugh just a little bit. You ought to be up here looking at yourself. See this little.
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Do you ever stop to think we're the only animals that can laugh? Let us know what we're laughing about, Sure. You might as well take advantage of it and prove right. Here we are, 7073ft above sea level, right here. We are literally on the top of a mountain. Yet this afternoon, if you people will look carefully in the rocks at your feet outside.
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You will see sea shells in the rocks, which will prove to you that you are now walking on what was once the bottom of an ancient sea. Yet you are on the top of a mountain. The land came upward in this region, and when you're in the bottom of this canyon, climbing up the trails, you will pass through seven separate, distinct layers of limestone, which will prove to you that this region has been above and below seas at least seven times.
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That's not counting on my little rock once above my head. Or you know I found so many people believe that seas come up over the land. You know, that's not so. We measure from sea level. It is the land that rises and falls. So then, fact number one, the river, its speed, its carrying power is force aided by fact.
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Number two, the uplift of the region made Grand Canyon. Now, of course, it all happened very recently. Two. Let's start at the beginning of things. Before the river and before the canyon was here. Let's take up Earth's history as exposed to view. And number three telescope. The approach to the ancient black rocks in the bottom of this canyon.
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And what you see down there is the base or roots of what was once a mighty mountain range in this region. We mountain range over six miles high. And we think of Mount Everest in Asia today. And those rocks were under that mountain range so far. And we're subjected to such terrific pressure and pressure, you know, generates heat so that those rocks down there are no more, no more, as they once were, or they are completely changed or a little particles floating up on it to resist that pressure and heat.
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They are known as change rock, metamorphic rock that geologists call them. And during the ages, that mountain range wore to a complete level playing. And the land in this region slowly slipped beneath an ancient freshwater sea. Completing chapter one the off years owing. Now, when the land came out of that ancient sea, it had another layer on it.
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The second chapter of life's history, seen through number four. Telescope there. And that layer of rock is also very, very old. But strange to say, it was not subjected to its greatest pressure and heat as the first rock. Hence, it still retains its original character as sands and silts and gravels and mud. And the land was low above sea level.
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And then terrific stresses and strains in this region broke the entire region up into gigantic great blocks, and then tilted those blocks up on end, making a second range of Black Mountains in this region. And during the ages, that mountain range wore off to almost a complete level plain. And again, the land slowly slipped beneath an ancient sea.
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Completing chapter two with appropriate what was going. Now, can you people grasp that two mighty mountain ranges in this region completely wearing away? And we think of everlasting rocks and everlasting mountains. Oh, we build monuments to our heroes. Tombstones to our dead. Three, four, five, 600 years from now. And you can't read them. You see, the trouble always is with us.
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Always. We are attempting to measure in our threescore and ten. And it just can't be done. Who? Listen. Number five. Telescope here. Points to the greatest single geological story in the entire canyon. For at this spot, the third chapter of its history, the Paleozoic rests smack on the first chapter of the Zoe. The second chapter in between or profile of Zoe.
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A mountain range of over 12,000ft has been worn completely away at this spot, leaving not a trace of meaning an absence of 500 million years. One spot in the canyon. In other words, it took 500 million years for the second geological here to form. Come up on the sea, be thrust into a mighty mountain range, and then to where?
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Completely away at this spot, leaving not a trace of scientists from all over the world come to Grand Canyon just to see this. Not the scenery out there, but this the Great Unconformity, as it is called. In other words, there you have an island, the first chapter of rocks sticking through the second chapter, upon which the third chapter formed.
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Oh, there's a sample of that rock on the bench there by the window. And the bottom part of it is brown. Chapter one the Office or Zoe? The upper part of it is gray. Chapter three The Paleozoic. Now, afterwards, you people take your finger. You take your finger. Place it where the two meet on that rock and spend an absence of 500 million years.
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Right. With your finger. That's enough to make anybody put on the brakes, And then, from the great green platform, 3200ft down to the top of the rim on which we now walk is all of the third chapter. And during the third chapter, there were many, many changes in this region. Halfway up the canyon, up there, you see that sheer red cliff or wall?
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We looked down at it here, by the way, and that cliff wall down there is over 555ft in height or thickness. There are caves and overhangs in that layer of rock, so large that you can tuck the Washington Monument in out of the rain, and that one layer of rock alone. Now, that was once the great oozy mud on the bottom of an ancient sea.
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It has no hardened turn to stone and is known as limestone. Seen through this telescope here. Now, when the land came out of that ancient sea, with that layer on it, it again was low above sea level. And then ancient rivers carrying mud, just like the Colorado River is carrying mud today. They dropped there much in this region, or it became a flood plain region.
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And it built up that series of little red cliffs and slopes above the sheer red wall to beneath that great white band or cliffs below the rim. Now that's all made of hardened river muds known as shales and the Great White Band, or cliff below the rim, running the entire length of the canyon out there tells us that the wind, the wind blew for ages in this region and blew sand until we had a condition here.
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Much like the Great Libyan or Great Sahara Desert of Africa, or it was a land of windblown sand dunes and practically not much else. And it rested on an ancient sea that lie to the northwest of us. And again, the land in this region slowly slip beneath that ancient sea, and the waves and the currents in the sea lapped off the tops of the sand dunes and spread the sand out into that great white band on the bottom of itself.
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It became the bottom of a sea. It has no heart and turned to stone, and is known as sandstone. And in that cliff today, by the way, you can still see the ancient sand dune lines, the long windward slopes, and the short leaf slopes bearing planes that geologists call them. Now, while that sand rested on the bottom of that sea, things living and dying in the sea settled to the bottom, on top of the sand, and built up another layer of great organic mud, which now was hardened, turned to stone, and is the limestone on which you and I now walk on the rims of Grand Canyon.
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Completing chapter three, the Paleozoic scene, through this telescope here. Now, how do you people begin to get an idea of land building and wearing away? Now, chapter four. The Mesozoic was once above our heads here. But because this is high land, land ways away from the high parts and has been worn off the top of Grand Canyon.
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But all around us, in the low parts, we still have it. Number 11 telescope. They approach to see the mountain 28 miles away. That low up flat table and peeking above the scallop ridge in the distance on the right. That is a remnant of the fourth chapter of its history. It has a gravel cap on the top of it, preventing it from eroding away rapidly.
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And you people on the bus this afternoon, when you get to Desert View at the tower, you will see it very close at hand. And you will also, by the way, be looking out over the Painted Desert and the Petrified Forest and the rocks of the Painted Desert and the Petrified Forest on the rocks of the fourth geological era, which once extended this way up and over our heads.
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Zion National Park in southern Utah, its canyon is caught in the rocks of the fourth chapter. Now the fifth chapter, which is the present, is not forming here. Land is wearing away. But as I stand here and I look to the west, I see a blue mountain range against the sky. The Trumble Range, 85 miles away, or Pine Mountain Range, that mountain ranges of the fifth and present chapter of Earth history.
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It is recently it volcanic Bryce Canyon National Park in southern Utah. Each canyon is cut in the rocks of the fifth chapter. And when you people get to Desert View this afternoon at the tower, you will be able to look south of us. And 50 miles south of us you will see another blue mountain range with snow capped peaks.
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The San Francisco Range at Flagstaff and Williams. And that mountain range is also of the fifth and present chapter of Earth's history. It was recent. It is volcanic, in fact, is rather an interesting highlight for you to carry away with you. Some of that activity south of us between Flagstaff and Grand Canyon here, has been so recent that beneath the volcanic ash layers of Sunset Crater, we have found Indian house ruins buried.
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And in digging out those house ruins, we found some of the roof beams. The roof beams were still preserved, and in cutting the roof beams across and sandpaper in the ends of them, there were the tree rings in the beams. And the tree rings gave up this secret. The tree rings told us that the Indians had cut those beams to build their house in 1046 A.D., and some of that action has taken place since the time of Christ.
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All of its history in the Grand Canyon region. Exposed to your view. And as I always say, show me another spot like you. You can do it. So here then, as nowhere else, Mother Nature literally opened up her history book of Earth's history for you and me to read all chapter upon chapter, paragraph upon paragraph, and illustrated with the life that once lived in those dim, distant past ages in the form of fossils.
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All right, let us take up life through the ages and download those ancient black rocks in the bottom of this canyon. No life. No life was ever found in those rocks. Wherever they are found on the face of the earth, no life was ever found in them. It is not believed that life ever existed at that time. However, if it did exist, it would have been completely destroyed due to the terrific pressure and heat to which those rocks have been subjected.
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But in the beginning, layers of the second chapter of life's history. Number seven telescope. Here they you see the first traces of living things entering Earth's picture. Oh, a little single celled, plant like life known as algae. You people know it is the green scum on ponds today. All that, all the living in that ancient sea consisted of tiny globules of jelly and living together in colonies.
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It made a jelly fied mass which caught the lime in the water and built up limestone reefs. And then you come up to the beginning layers of the third chapter of life's history. Number eight telescope here and there. Now, lo and behold, you find the first traces of animal life entering the picture. All the little crab like creature known as a trail of bite.
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And, you know, I think that's interesting, Plants come first, Animals that live on plants afterwards. You couldn't put them around the other way, could you? Think it over. And then as you come up those canyon walls, layer by layer, higher and higher, all you see life becoming higher and higher and more and more complicated. Preserved in the rocks in the form of fossils.
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Oh, you're coming a little higher. And now you're finding two fish. You come a little higher. And now, for the first time, you are finding land plants, ferns and cones, ancestors to alpine trees. Before that, all life in water. Now life is leading water, coming up on land. You come a little higher to those layers of hardened river muds out there.
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And there you find the tracks of those creatures that lived in water and on land. Amphibians that call you see where they left the water, climbed up on the muddy banks, left their tracks in the mud, which now is hardened and turned to stone. Oh, there's some excellent examples of those tracks built in the wall right there next to the opening and on the bench over there.
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And then? And then you come up to the fourth chapter of Earth's history, which once covered our heads and which is the Painted Desert to the east of us. It is also represented by the Gobi Desert of Mongolia. The purpose of the Argentine and their. Oh, you find those gigantic lizards known as dinosaurs, creatures weighing many, many tons in weight, consuming thousands of pounds of food a day.
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Oh, having enormous tails and little heads in front. In fact, I've even heard it said they used over 90% of their brain to wag their tail. Yeah, and didn't have sense enough to live today. Now, here's where I get the kick out of it. I don't know whether you people will or not. There are only five chapters in Earth's history.
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That's all the is. There isn't any more. We just now briefly came up through all four of them. And not a warm blooded animal has made its appearance on the face of the earth. All cold blooded creatures. It's only in the fifth. And that's the present that warm blooded animals appear. It is known as the Age of Mammals.
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And now listen. The present sentence now being written. Geologically speaking, we man first enters its picture. Oh, we are the youngest of living things. And you know, I sometimes wonder if any of my listeners subconsciously, of course, have an inflated ego and.
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Or a superiority complex, whether they will lose that and become humble when they grasp the story that Grand Canyon has to tell. Who? Listen. I told you this was a young canyon out here just several million years old. And there is the Great Unconformity, an absence of 500 million years in the ancient black rocks in the bottom of this canyon by radioactive disintegration of metals is 1,500,000,000 years old.
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Now, Cro-Magnon man, the first true man in the man that you and I would recognize as a man. So he had a chin. He had a chin. The fellows before that did not have a chin. Yes. Even though the chin was the first thing was civilized. Come to think of it, he's been sticking around ever since to and then he was rather good looking, according to our standards, taller than we were.
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He made those wonderful drawings in the caves of France and Spain. The scientist called him Homo sapiens man. The wise or wise man. Now, he added, respected between 25 and 40,000 years ago. And as you people stand on the rim of Grand Canyon and look out over it and then think, think of your threescore and ten. Do you get what I mean?
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I mean, you suddenly begin to realize that our lives just like the click of a camera, shut up. In the scheme of things, up there. And as I always say, I'm sure your resolve to live by the wayside as you travel through life. Oh you bet. Think it over before it's too late. You can do that. Maybe it is too late with this atom bomb.
00;39;12;25 - 00;39;45;16
I wonder what you intend on then. The canyon is another story. It's 217 miles long, has an average width of ten miles, and is a mile in depth. Can you visualize it? What does it mean? It means it's a barrier. Before that canyon was cut, the smaller creatures intermingled. They were the same species. But when the canyon was cut, those corner on the North rim, across the canyon over there found themselves separated from their brethren on this side.
00;39;45;19 - 00;40;13;04
They over there found themselves 1000 to 2000ft higher than their brethren on this side. A changing environment over there. They had to adapt themselves to it or die. Until today, they have changed the squirrel on the North Rim. Of course, the canyon over there has a pure white tail and black belly pods. That squirrel on this side has a great tail and white belly pods.
00;40;13;06 - 00;40;38;11
The stripes on the chipmunks back have changed. The porcupines. The pack rats. The puppet gophers. The reptiles. They no longer could cross Grand Canyon. It became a barrier. Not a physical barrier, but a climatic barrier. The ocean is a barrier to us today. Right opposite the station. On the top. Over there. If you look carefully, you see the hotel Grand Canyon Lodge, just ten miles away.
00;40;38;13 - 00;41;06;17
Now you want to go there in your automobile. Do you know what you must do? Travel each 25 miles to desert you, then 32 miles to the trading post of Cameron Cross. The Painted Desert sacred, the Echo Cliffs. Of course, this river at Navajo Bridge and Marble Canyon scraped off a million cliffs. Of course. House Rock Valley. Go through the Kaibab Forest and you will have traveled 215 miles in your automobile to reach that spot.
00;41;06;23 - 00;41;30;24
Just ten miles away. She went to bury the canyon. All you can cross here on your back. But it takes you two days. You have to spend the night at Phantom Ranch in the bottom of the canyon. And then you wonder whether you ever get over it or not. To to leave an impression one way or the other.
00;41;30;27 - 00;41;56;19
Then the canyon has another story. It's a mile in depth, 50 miles south of us on the San Francisco Peaks, the highest peaks in Arizona, 12,655ft in height. Now, what does that mean? It means just this. That of the seven climatic life zones of the world, there are only seven from the equator to the poles. Six of them are represented right here in the Grand Canyon region.
00;41;56;22 - 00;42;16;22
The only one missing is the humid tropical zone of the equator. We have all the rest down in the palm of this canyon. It is always hot, as a rule, 20 to 30 degrees hotter than this rim, 30 to 30 5 to 40 degrees hotter than the North Rim. Across the canyon, on the North Rim, across the canyon over there.
00;42;16;29 - 00;42;54;28
We have over 210 inches of snow in the wintertime. They're snowed in for months out of the year. The Ranger's patrol on skis and snowshoes. While on this rim, we only have 96in of snow. And in between, down in the bottom of the canyon, it never snows right within a radius of ten miles. Oh, I might qualify that statement by telling you that if it happens to be an exceptionally cold winter's night and snow falls, you might find a little powdered snow on that great green platform 3200ft down.
00;42;55;01 - 00;43;18;13
But by 9:00 in the morning, it's all gone. So for ordinary people, we should never snows in the bottom of the canyon. Very, very rarely do they have frost at Phantom Ranch. They broke pomegranates down there. Hence, the plants and animals that live at the bottom of this canyon are not the plants and animals you find living on this rim or that rim over there.
00;43;18;16 - 00;43;39;01
They are the plants and animals of that dry, hot, arid region of Sonora, Mexico. They are the cat claw, the mesquite, the number one yucca, the saltbush, the tropical walnut lizard, the pink rattlesnake. You don't find them on the. Why last forest you see on the top over there is not the forest you are driving through or walking through on this side.
00;43;39;03 - 00;44;04;08
That forest over there is a forest of Canada for spruce and quaking aspen. Now listen. It's only 14 miles by trail from the bottom of the canyon to the top of the North Rim. Yet, if you wish to travel through those climatic life zones at sea level, you would have to travel from central Mexico to southern Canada to pass through them.
00;44;04;11 - 00;44;33;17
Where? Here you can do it by 14 miles of trail. And if that doesn't satisfy you, just 30 miles south of the rim, the foothills of the Frisco Peaks, you go up into those foothills and there you get a hot zone and life zone, just like the Hudson Bay region of Canada. Go up into the San Francisco Peaks of Flagstaff, 50 miles south of us, above timberline, and there you get an Arctic alpine zone, just like the Arctic Circle, right within a radius of 50 miles.
00;44;33;19 - 00;44;56;29
Now, the facts of those two stories are shown in the end, two telescopes there and the end two cases inside. So you see, there are stories behind Grand Canyon. Get some of those stories before you go away. Then when you sit by your fireside, you'll remember Grand Canyon. You can't shake it off because you're going to get thoughts or concepts here you would not ordinarily get anywhere else.
00;44;57;06 - 00;45;19;07
You may have five left, 1 or 2 with you, have I? Did you get that feeling of duration, timelessness of time, mountains where in a way season a year seven different times or you'll get others. Now each one of these is the fact you people reason on these facts. Hook up together and check that story I just told you.
00;45;19;09 - 00;45;38;26
Now you're in one of your national parks, and your national parks have been set aside so that there shall always be a bit of wilderness in these United States, not only for us, but for our children and our children's children yet to come. And you know, we need the wilderness. The good old book admonishes us to go out into the wilderness.
00;45;38;28 - 00;46;04;27
The prophets went out into the wilderness. So we fellows say to you, come on out into your wilderness, and we believe you will get the strength of the mountains, and your cares and your worries will fall from you like the leaves from the trees. And you will go home re-created, not recreated. Thank you.
2026 marks 100 years of National Park Service Interpretation at Grand Canyon National Park. In honor of this anniversary, here's Louis Schellbach's introductory geology talk. Throughout his talk, he references geologic details once viewed through a series of mounted binoculars on the parapet at Yavapai Observation Station (now Yavapai Geology Museum). Schellbach served as the park's Chief Naturalist from 1941–1957.