Exotic terranes

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A schedule of arrivals of incoming exotic terranes will account-as a simple continent-to-continent collision cannot do-for the long spreads of time between one and another of the Appalachian mountain-building pulses. As someone once compacted it for me, “you sweep the New Zealands and Madagascars out of the ocean and then you close it with the Alleghenian Orogeny.” Disagreeing interpreters see terranes of highly varied dimension. Nominated as the terrestrial remains of one exotic block is the whole of New England from Williamst own eastward, arriving in the Ordovician to lift the Taconic mountains. Exotic terranes and their effects represent only one of the responses of plate-tectonic theorists to the embarrassment caused by the failure of Exhibit A among intercontinental collisions to exhibit a finite suture. Another response conference room leeuwarden has been the notion that when two continents collide there is every possibility that one will split the other, like an axe blade entering cedar; if so, you would find the invaded country rock both above and below the invader. The concept is known as flake tectonics. Its message to Vibroseis is to stop
shaking and go home. With a little erosion and flake tectonics, you can have the native rock reaching far under the rock from across the sea. Even so, the bunching of exotic terranes seems to solve more problems than flake tectonics does. Exotic terranes not only explain the intervals of time involved in the Taconic, Acadian, Alleghenian orogenies, they suggest as well why Taconic deformation occurred in the nmthem but not the southern Appalachians. Shortening collisional boundaries, they restore some dignity to the Brevard suture. Anita turned on the windshield wipers and wiped an April shower. Beside the interstate, the Pocono Devonian roadcuts were of much the same age and character as ones we had seen before. We conference room eindhoven passed them by. “Better not to do geology in the rain,” Anita said. “It’s unfair to the rocks.” With regard to the possibility of exotic terranes having added themselves to eastern North America, she said, “If you stretch out the overthrusts in the Appalachians, they show that-before the mountain building began-the continent was much larger than it is now, not smaller.”

The scientist

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The scientist has something to do, and is almost certain to do it, if he lingers there for any considerable period. He may not have quite decided how Niagara comes to be where it iswhether it was originally in the same place, or down at the mouth of the St. Lawrence; but he will find himself joining in the scientific speculations of the past half-century, as to whether the Water Gap changed to be what it is at the Flood; or whether some immense freshet broke through the barriers once standing across the way and let out what had been the waters of an immense inland lake.” By 1877, Kittatinny House was five stories high. Harper’s Weekly, at the end of the season, ran a wood engraving of the Water Gap in color by Granville Perkins, who had co-working space leeuwarden taken enough vertical license to outstretch El Greco. Under the enlofted mountain, a woman reclined on the riverbank with a pink parasol in her hand. A man in a straw boater, dark suit, was stretched beside her like a snake in the grass. In the crossbedding and planar bedding of the Bloomsburg rocks, as we slowly traced them forward through time, there had been evidence of what geologists call the “lower upper flow regime.” That was now becoming an “upper lower flow regime.” When people were bored with the river, there were orchestras, magicians, lecturers, masquerade balls. They could read one another’s blank verse:
Huge pile of Nature’s majesty! how oft The mind, in contemplation wrapt, has scann’d Thy farm serene and naked; if to tell, That when creation from old chaos rose, Thou wert as now thou art; or if some cause, Some secret cause, has rent thy rocky mantle, And hurl’d thy fragments o’er the plain below. The pride of man may form conceptions vast, Of all the fearful might of giant power That rent the rampart to its very base, Giving an exit to Lenape’s stream, And wildly mixing with woods and waters. A mighty scene to set enchantment free, Burst the firm barrier of eternal rock, If by the howling of volcanic rage, Or foaming terror of Noachian floods. Let fancy take her strongest flight. . . . But, as for us, let speculations go, And be the food of co-working space eindhoven geologic sons; Who from the pebble judge the mountain’s form …
Anita said the rock had been weakened here in this part of the mountain. The river, cutting through the formations, had found the weakness and exploited it. “Wherever a water gap or a wind gap exists, there is generally tectonic weakness in the bedrock,” she went on. “The rock was very much fractured and shattered. There is particularly tight folding here.”

The morning shadow

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It stands in the morning shadow of the Annieopsquotch Mountains, of the Green Mountains, of the New Jersey Highlands, of the Berkshire, Catoctin, and Great Smoky Mountains, which are fraternal in structure and composition and are all of Precambrian age. The lookoff where we stood was a part of that Appalachian complex. It was crystalline rock above a thousand million years old-and the rock in the valley was younger, and in the Kittatinny younger still. (Geologists avoid the word “billion” because in one part and another of the Englishspeaking world the quantity it refers to differs by three orders of magnitude. A billion in Great Britain is a million million.) We were looking from the New Jersey Highlands into another segment of the cordillera-the beginnings of the physiographic Ridge and Valley Province, the folded-and-faulted deformed Appalachians, the long ropy ridges of the eastern sinuous welt, which Edmund Wilson had once written off as “fairly unimportant creases in the earth covered with trees.” “Geology repeats itself,” Anita remarked, and she went on to say that anyone who could understand the view before us would have come to flexplek huren leeuwarden understand in a general way the Appalachians as a whole-that what we were looking at was the fragmental evidence and low remains of alpine massifs immeasurably high and wide, massifs which for the most part had stood behind us to the east, and were now largely disintegrated and recycled into younger rock that is tens of thousands of feet deep and wedges out to the west in everdiminishing quantity until what covers Ohio is a thin veneer. The appearance of a country is the effect primarily of water, running off the landscape, cutting out valleys, dozing wantonly as glacier ice. The sculpturing is external. But it is influenced and can even be controlled by the rock within: by the relative strength, not to mention the solubility, of successive strata, and by the folds and faults-the structure-that the rock has been given. Figuring out the Appalachians was Problem i in American geology, and a difficult place to begin, for it was scarcely a matter of layer-cake legibility, like the time scale in the walls of the Grand Canyon. It was flexplek huren eindhoven a compressed, chaotic, ropy enigma four thousand kilometres from end to apparent end, full of overturned strata and recycled rock, of steep faults and horizontal thrust sheets, of folds so tight that what had once stretched twenty miles might now fit into five.

Ocean Parkway

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North over the outwash plain we followed Ocean Parkway five miles-broad, tree-lined Ocean Parkway, with neat houses in trim neighborhoods, reaching into shaded streets. Ahead, all the while, loomed the terminal moraine, suggesting, from a distance, an escarpment, but actually just a fairly steep hill. Eastern Parkway defines its summit, two hundred feet high. Two hundred feet of till. Near Prospect Park you begin to climb. One moment you are level on the plain and the next you are nose up, gaining altitude. There are cemeteries in every direction: Evergreens Cemetery, Lutheran Cemetery, Mt. Carmel, Cypress Hills, flexplek huren groningen Greenwood Cemetery-some of the great necropolises of all time, with three million under sod, moved into the ultimate neighborhood, the terminal moraine. “In glacial country, all you have to do is look for cemeteries if you want to find the moraine,” Anita said. “A moraine is poor farmlandsteep and hummocky, with erratics and boulders. Yet it’s easy ground to dig in, and well drained. An outwash plain is boggy. There’s a cemetery over near Utica Avenue that’s in the outwash. Most people prefer moraine. I would say it’s kind of distasteful to put your mother down into a swamp.” Ebbets Field, where they buried the old Brooklyn Dodgers, was also on the terminal moraine. When a long-ball hitter hit a long ball, it would land on Bedford Avenue and bounce down the morainal front to roll toward Coney on the outwash plain. No one in Los Angeles would ever hit a homer like that. We detoured through Prospect Park, which is nestled into the morainal front. and is studded with big erratics on raucously irregular ground. It looks much like Pokagon Park, in Indiana, with the difference that the erratics there flexplek huren den haag are from the Canadian Shield and these were from the New Jersey Palisades. Pieces of the Adirondacks have been found ill Pennsylvania, pieces of Sweden on the north German plains, and no doubt there is Ticonderoga dolomite, Schenectady sandstone, and Peekskill granite in the gravels of Canarsie and the sands of Coney Island.

Uinta Mountains

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I asked him if he thought the Uinta Mountains could be explained in terms of plate theory. The Uintas are a range in the Rockies, seven hundred miles from the sea, and they run east-west, unlike virtually all other ranges for thousands of miles around them. If the Western cordilleras were raised by colliding plates, how did the Uintas happen to come up at right angles to the other mountains? He said, “You must have been talking to a Rocky Mountain geologist.” He said nothing else for a time, while he tapped at the earth I had uncovered and captured a perfect sample. Then he said, “The north side of the Uintas is a spectacular mountain wall. Glorious. You come upon it and suddenly you see structurally the boundary of the range. But you don’t see what put it there. The Uintas are mysterious. They are not a basin-range fault block, yet they have come up nearly vertically, with almost no compression evident. You just stand flexplek huren leeuwarden there and watch them go up into the sky. They don’t fit our idea of plate tectonics. The Rockies in general will be one of the last places in the world to be deciphered in terms of how many hits created them, and just when, and from where.” The article in Geology was based on a questionnaire that was circulated toward the end of the nineteen-seventies. The results indicated that forty per cent of geologists had come to feel that plate theory was “essentially established,” while a roughly equal number preferred to qualify a bit and say that it was “fairly well established.” Eleven per cent felt that the theory was “inadequately proven.” Seven per cent said they had accepted continental drift before i940. Six per cent thought plate tectonics would be “still in doubt” in the late nineteen-eighties. And one flexplek huren eindhoven geologist predicted that the theory would eventually be rejected. “At any given moment, no two geologists are going to have in their heads exactly the same levels of acceptance of all hypotheses and theories that are floating around,” Deffeyes said. “There are always many ideas in various stages of acceptance.

The little stream

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The little stream was a jumble of boulders, testimony of the floods, with phreatophytes around the boulders like implanted spears. Deffeyes obviously was happy and without a fear in the world. When a swift-rising wind blew dust in his face, he mooed. Working in cold sunshine with his orange-and-black conical cap on his head, he appeared to be the Gnome of Princeton, with evident ambition to escalate to Zurich. To make a recovery operation worthwhile, he said, he would have to get five ounces of silver per ton. The figures would tum out to be better than that. Before long, he would have a little plasticlined pond of weak cyanide, looked after by a couple of technicians, down where the ore from this mine had been milled. A blue  zakelijke energie streak in the tailings there would come in at fifty-eight ounces a tonricher than any tailings he had ever found in Nevada. “You put cyanide on that ore, the silver leaps out of it,” he would say. “I have enough cyanide there to kill Cincinnati. People have a love-hate relationship with cyanide. Abelson showed that lightning acts on carbon dioxide and other atmospheric components to make hydrogen cyanide, and hydrogen cyanide polymerizes and later reacts with water to form amino acids, which are the components of proteinsand tl1at may be how life began. Phil Abelson is an editor at Science. He’s a geochemist, and he worked on the Manhattan Project. To get the silver out of here at an acceptable price, you need small-scale technology. You need miniaturized equipment, simple techniques. In the nineteenth century, they made sagebrush fires to heat the brine to dissolve tl1e silver chloride. When mercury picked up the silver, they knew they had ‘the real stuff’ from the squeak. A mercury-and-silver mixture is what the dentist uses, and when he mashes it into your tooth it makes the same squeak.” Deffeyes’ methodology would depend on more than sagebrush and sound. In time, he would have a portable laboratory zakelijke energie vergelijken there, size of a two-hole privy, and in it would be, among other things, a silver single-ion electrode and an atomic-absorption spectrophotometer. He could turn on a flame, close two switches, and see at once the amount of silver in a sample.

A paragraph in literature

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Ignoring its geology, I guess I don’t know a paragraph in literature that I prefer to the one Joseph Conrad begins by saying, “Going up that river was like travelling back to the earliest beginnings of the world, when vegetation rioted on the earth and the big trees were kings.” He says, moments later, “This stillness of life did not in the least resemble a peace. It was the stillness of an implacable force brooding over an inscrutable intention. It looked at you with a vengeful aspect. I got used to it afterwards; I did not see it anymore; I had no time. I had to keep guessing at the channel; I had to discern, mostly by inspiration, the signs of hidden banks; I watched for sunken stones.” Metaphorically, he travelled back to the Carboniferous, when the vegetal riot occurred, but scarcely was that the beginning of the world. The first zakelijke energie plants to appear on land, ever, appeared in the Silurian. Through the Ordovician and the Cambrian, there had been no terrestrial vegetation at all. And in the deep shadow below the Camb1ian were seven years for every one in all subsequent time. There were four billion years back there-since the earliest beginnings of the world. There were scant to nonexistent fossils. There were the cores of tl1e cratons, the rock of the continental shields, the rock of the surface of the moon. There were the reefs of the Witwatersrand. There was the rock that would become the Adirondack Mountains, the Wind River summits, the Seward Peninsula, Manhattan Island. But so little is known of this seveneighths of all history that in a typical two-pound geological textbook there are fourteen pages on Precambrian time. The Precambrian has attracted geologists of exceptional imagination, who see families of mountains in folded schists. Uranium-lead, rubidium-strontium, and potassium-argon radiometric dating have helped them to sort out their Kenoran, Hudsonian, Grenvillean orogenies, their Aphebian, Hadrynian, Paleohelikian time. Isolating the first . two billion years of the life of the earth, they called it the Archean Eon. In the middle zakelijke energie vergelijken Archean, photosynthesis began. Much later in the Precambrian, somewhere in Helikian or Hadrynian time, aerobic life appeared. There is no younger rock in the United States than the travertine that is forming in Thermopolis, Wyoming. A 2.7-billionyear-old outcrop of the core of the continent is at the head of Wind River Canyon, twenty miles away. Precambrian-4,560 to 544 million years before the present.

The blind men and the elephant

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The blind men and the elephant are kept close at hand mainly to slow down what some graduate students refer to as “arm waving” -the delivery, with pumping elbows, of hypotheses so breathtakingly original that the science seems for the moment more imaginative than descriptive. Where it is solid, it is imaginative enough. Geologists are famous for picking up two or three bones and sketching an entire and previously unheard-of creature into a landscape long established in the Picture. They look at zakelijke energie mud and see mountains, in mountains oceans, in oceans mountains to be. They go up to some rock and figure out a story, another rock, another story, and as the stories compile through time they connect-and long case histories are constructed and written from interpreted patterns of clues. This is detective work on a scale unimaginable to most detectives, with the notable exception of Sherlock Holmes, who was, with his discoveries and interpretations of little bits of grit from Blackheath or Hampstead, the first forensic geologist, acknowledged as such by geologists to this day. Holmes was a fiction, but he started a branch of a science; and the science, with careful inference, carries fact beyond the competence of invention. Geologists, in their all but closed conversation, inhabit scenes that no one ever saw, scenes of global sweep, gone and gone again, including seas, mountains, rivers, forests, and zakelijke energie vergelijken archipelagoes of aching beauty rising in volcanic violence to settle down quietly and then forever disappear-almost disappear. If some fragment has remained in the crust somewhere and something has lifted the fragment to view, the geologist in his tweed cap goes out with his hammer and his sandwich, his magnifying glass and his imagination, and rebuilds the archipelago.

Geology Department

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Deffeyes became excited as we approached Hook Mountain. The interstate had blasted into one toe of the former peninsula, exposing its interior to view. Deffeyes said, “Maybe someone will have left some zeolites here. I want them so bad I can taste them.” He jumped the curb with his high-slung Geology Department vehicle, got out his hammers, and walked the cut. It was steep and competent, with brown oxides of iron over the felt-textured black basalt, and in it were tens of thousands of tiny vugs, a high percentage of them filled with pearl-lustred crystals of zeolite. To take a close look, he opened his hand lens-a small-diameter, ten-power
Hastings Triplet. “You can do a nice act in a jewelry store,” he suggested. “You whip this thing out and you say the price is too high. These are beautiful crystals. Beautiful crystals imply slow growth. You don’t get in a hurry and make something that nice.” He picked up the sledge and pounded the cut, necessarily smashing many crystals as he broke their matiix free. “These crystals are like Vietnamese villages,” he went on. “You have to destroy them in order to preserve them. They contain zakelijke energie vergelijken aluminum, silicon, calcium, sodium, and an incredible amount of imprisoned water. ‘Zeolite’ means ‘the stone that boils.’ If you take one small zeolite crystal, of scarcely more than a pinhead’s diameter, and heat it until the water has come out, the crystal will have an internal surface area equivalent to a bedspread. Zeolites are often used to separate one kind of molecule from another. They can, for example, sort out molecules for detergents, choosing the ones that are biodegradable. They love water. In refrigerators, they are used to adsorb water that accidentally gets into the Freon. They could be used in automobile gas tanks to adsorb water. A zeolite called clinoptilolite is the strongest adsorber of strontium and cesium from radioactive wastes. The clinoptilolite will adsorb a great deal of lethal material, which you can then store in a small space. When William Wyler made The Big Country, there was a climactic chase scene in which the bad guy was shot and came clattering down a canyon wall in what appeared to be a shower of clinoptilolite. Geologists were on the phone to Wyler at once. ‘Loved your zakelijke energie movie. Where was that canyon?’ There are a lot of zeolites in the Alps, in Nova Scotia, and in North Table Mountain in Colorado. When I was at the School of Mines, I used to go up to North Table Mountain just to wham around. Some of the best zeolites in the world are in this part of New Jersey.”

The Williamsburg section of Brooklyn

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Anita Harris grew up in the Williamsburg section of Brooklyn and frankly went into geology in order to get out of the city. Within the profile of her is a profile of New York City geology (157-67). Her international reputation is mainly the result of paleontol9gical discoveries that have enhanced the search for oil. I accompanied her as she collected carbonate rocks from New Jersey to Indiana. In the zakelijke energie context of Appalachian history-among mountains that are thought by many to represent the suturing of two continents-her cautionary remarks about plate theory are given unrestrained expression, notably on pages 147-49, 217-32, and 274-75. Rising from the Plains is primarily about Wyoming, which includes within its borders an exceptional range of geology. It’s about the roadcuts of the interstate but also about Jackson Hole and the Tetons and the Powder River Basin and the Wind River Basin and the Laramie Range and David Love and his father and especially his mother, who educated her children at Love Ranch, a very long ride from neighbors, in the geographical center of Wyoming. She was born in 1882 and died long before I would have had a chance to meet her, but she is probably the most arresting personality I have encountered in the course of my professional work. You will find the story of the Laramide Orogeny-the rising of the Rocky Mountains-on pages 310-12, the burial and exhumation of the Rockies on pages 313-16, a set piece on the geologic history of Jackson Hole and the Tetons (understand a fragment …) on pages 366-78, and a set piece on the theory of geophysical hot spots (such as Yellowstone, Hawaii, Bermuda, Iceland, Tristan da Cunha, Mt. Cameroon) on pages 388-403, preceded by a passage on the tension between field geology and “black-box geology” (380-86). Sometimes it is said of geologists that they reflect in their zakelijke energie vergelijken professional styles the sort of country in which they grew up. Nowhere could that be better exampled than in the life of a geologist born in the center of Wyoming. The passages on Love Ranch and the years of David Love’s upbringing are on pages 281-82, 287-94, 299-308, and 332-56.