Established tectonic velocities

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Conversely, it is possible to use established tectonic velocities to chart the tracks of hot spots with respect to the overriding plates. Given just one position and one date (the present will do), it is possible to say where, under the world, a hot spot would have been at any time across a dozen epochs. W. Jason Morgan, a geophysicist at Princeton, has sketched out many such tracks and reported them in various publications. Morgan can fairly be described as an office geologist who spends his working year indoors, and he is a figure of first importance in the history of the science. In ig68, at the age of thirty-two, he published one of the last of the primal papers that, taken together, constituted the plate-tectonics revolution. Morgan had  been zakelijke energie trained as a physicist, and his Ph.D. thesis was an application of celestial mechanics in a search for fluctuations in the gravitational constant. Only as a postdoctoral fellow was he drawn into geology, and assigned to deal with data on gravity anomalies in the Puerto Rico Trench. Fortuitously, he was assigned as well an office that he shared for two years with Fred Vine, the young English geologist who, with his Cambridge colleague Drummond Matthews, had discovered the bilateral symmetry of the spreading ocean floor. This insight was fundamental to the revolutionary theory then developing, and sharing that office with Fred Vine drew Morgan into the subject-as he puts it-“with a bang.” A paper written by H. W. Menard caused him to begin musing on his own about great faults and fracture zones, and how they might relate to theorems on the geometry of spheres. No one had any idea how the world’s great faults-like, say, the zakelijke energie vergelijken San Andreas and Queen Charlotte faultsmight relate to one another in a system, let alone how the system might figure in a much larger story. Morgan looked up the work of field geologists to learn the orientations of great faults, and found remarkable consistencies across thousands of miles.

Cheyenne to Bombay

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When Hollywood took up the story, though, and prepared to spread it from Cheyenne to Bombay, the valley that Shane would ride into seemed an almost automatic choice. Its floor, as he slowly moved across it, was generally as flat as the bottom of a lake. Incongruous in its center were forested buttes, with clear cold streams running past them. In many places, the flatness was illusory, for there was random undulation and, for no apparent reason, a lyrical quilting of stands of dark pine and broad open stretches of pale-green sage. There were ponds, some of them zakelijke energie vergelijken warm enough to hold trumpeter swans for the winter; and lying against the higher mountains were considerable lakes. Mountains were everywhere. On three sides of the valley, they went up in fairly stiff gradients-the Mt. Leidy Highlands, the Gros Ventre Mountains, the Snake River Range. On the western sidewithout preamble, without foothills, with a sharp conjunctive line at the meeting of flat and sheer-were the Tetons, which seemed to have lifted themselves rapidly past timberline in kinetic penetration of the sky. The Tetons resemble breasts, as will any ice-sculpted horn-Weisshorn, Matterhorn, Zinalrothorn-at some phase in the progress of its making. Hollywood cannot resist the Tetons. If you have seen Western movies, you have seen the Tetons. They have appeared in the background of countless pictures, and must surely be the most tectonically active mountains on film, drifting about, as they will, from Canada to Mexico, and from Kansas nearly to the coast. After the wagon trains leave Independence and begin to move westward, the Tetons soon appear on the distant horizon, predicting the beauty, threat, and promise of the quested land. After the wagons have been moving for a month, the Tetons are still out there ahead. Another fortnight and the Tetons are a little closer. The zakelijke energie Teton Range is forty miles long and less than ten across-a surface area inverse in proportion not only to its extraordinary ubiquity but also to its grandeur. The Tetons-with Jackson Hole beneath them-are in a category with Mt. McKinley, Monument Valley, and the Grand Canyon of the Colorado River as what conservation organizations and the Washington bureaucracy like to call a scenic climax.

Private circulation

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People like that came along with such frequency that David’s mother eventually assembled a chronicle called “Murderers I Have Known.” She did not publish the manuscript, or even give it much private circulation, in her regard for the sensitivities of some of the first families of Wyoming. As David would one day comment, “they were nice men, family friends, who had put away people who needed killing, and she did not wish to offend them-so many of them were such decent people.” One of these was Bill Grace. Homesteader and cowboy, he was one of zakelijke energie vergelijken the most celebrated murderers in central Wyoming, and he had served time, but people generally disagreed with the judiciary and felt that Bill, in the acts for which he was convicted, had only been “doing his civic duty.” At the height of his fame, he stopped at the ranch one afternoon and stayed for dinner. Although David and Allan were young boys, they knew exactly who he was, and in his presence were struck dumb with awe. As it happened, they had come upon and dispatched a rattlesnake tlmt day-a big one, over five feet long. Their mother decided to serve it creamed on toast for dinner. She and their father sternly instructed David and Allan not to use the word “rattlesnake” at the table. They were to refer to it as chicken, since a possibility existed that Bill Grace might not be an eater of adequate sophistication to enjoy the truth. The excitement was too much zakelijke energie for the boys. Despite the parental injunction,
gradually their conversation at the table fished its way toward the snake. Casually-while the meal was going down-the boys raised the subject of poisonous vipers, gave their estimates of the contents of local dens, told stories of snake encounters, and so forth. Finally, one of them remarked on how very good rattlers were to eat. Bill Grace said, “By God, if anybody ever gave me rattlesnake meat I’d kill them.” The boys went into a state of catatonic paralysis. In the pure silence, their mother said, “More chicken, Bill?” “Don’t mind if I do,” said Bill Grace.

Out here

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“Out here, Uncle Sam is a gnat under a blanket compared to Uncle Pete. The Union Pacific had the best of it. This Miocene Ogallala formation was the youngest of the high-plains deposits that lapped onto the mountain front. It’s subtle and seems academic until you try to build a railroad. This is the only place in the whole Rocky Mountain front where you can go from the Great Plains to the summit of the mountains without snaking your way up a mountain face or going through a tunnel. This one feature had more to do with the building of the West than any other factor. I don’t diminish the importance of the Oregon Trail, but here you had everything going for you. This point hasn’t been made before.” When the railroad was built, it was given (by the federal govemment) fifty per cent of the land in a forty-mile swath along its route-in checkerboard fashion, one square mile in every two. Uncle Pete is so big that he has spun off, among many things, the Rocky Mountain Energy Company, the Upland Industries Corporation, the Champlin Petroleum Company, and enough unmined uranium to send zakelijke energie Wyoming to the moon. In Cheyenne, the Union Pacific station and the state capitol face each other at opposite ends of Capitol Avenue. The Union Pacific station came out of the Laramie Range, forty miles west, and, like the range itself, is sheathed in the russet Pennsylvanian sandstone and has a foundation of Precambrian granite. At least as imposing as the capitol, it is a baronially escutcheoned mountain of grandeur. Indians, of course, had used the gangplank for who knows how long before General Dodge surprised them on the Laramie summit. They had crossed it on their journeys from the Great Plains to the Laramie Basin and on up to hunting grounds in the Medicine Bow Mountains. And the Indians, from the beginning, were themselves following a trail. Buffalo discovered the gangplank. “It was a buffalo trail,” Love said. “Buffalo were the real zakelijke energie vergelijken trailmakers-trails you wouldn’t believe. They were as good as the best civil engineers. It remains true today. If you’re in Yellowstone, in the backcountry, and you have trouble finding your way across swamps, mountains, and thermal areas, you look for a buffalo trail and you’ll get through.” Beside Interstate 80 on the gangplank, a sign said, “GAME CROSSING.”

The oldest river

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Wyoming, at first glance, would appear to be an arbitrary segment of the country. Wyoming and Colorado are the only states whose borders consist of four straight lines. That could be looked upon as an affront to nature, an utterly political conception, an ignoring of the outlines of physiographic worlds, in disregard of rivers and divides. Rivers and divides, however, are in some ways unworthy as boundaries, which are meant to imply a durability that is belied by the function of rivers and divides. They move, they change, and they go away. Rivers, almost by definition, are young. The oldest river in the United States is called the New River. It has existed (in North Carolina, Virginia, and West Virginia) for a little more than one and a half per cent of the history of the world. In epochs and eras before there ever was a Colorado River, the zakelijke energie vergelijken formations of the Grand Canyon were crossed and crisscrossed, scoured and dissolved, deposited and moved by innumerable rivers. The Colorado River, which has only recently appeared on eaith, has excavated the Grand Canyon in very little time. From its beginning, human beings could have watched the Grand Canyon being made. The Green River has cut down through the Uinta Mountains in the last few million years, the Wind River through the Owl Creek Mountains, the Laramie River through the Laramie Range. The mountains themselves came up and moved. Several thousand feet of basin fill has recently disappeared. As the rock around Rawlins amply shows, the face of the country has frequently changed. Wyoming suggests with emphasis the page-one principle of reading in rock the record of the earth: Surface appearances are only that; topography grows, shrinks, compresses, spreads, disintegrates, and zakelijke energie disappears; every scene is temporary, and is composed of fragments from other scenes. Four straight lines-like a plug cut in the side of a watermelon-should do as well as any to frame Wyoming and its former worlds. A geologist who grew up in Wyoming has grown up among
mountains that in terms of plate-tectonic theory are the least explainable in the world.

Kelleys Island

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Kelleys Island stands high because it is a piece of the structural arch. While the Wisconsinan ice sheet was excavating the Great Lakes, reaming out whole networks of streams and carrying away the prominent features of their valleys, it bevelled but could not destroy the resistant structural arch. An engulfed ridge stood up from the bottom of the primal lake. With the weight of the ice gone, all of northern America slowly rebounded. A large part of the water gradually drained away, leaving Kelleys Island dry in the air, sixty feet above the level of Lake Erie. We passed the island cemetery, its names recorded in limestone. We came to the north shore, where the beginnings of a quarrying operation had revealed how the ice had cut its kantoor per uur almere tracks into the rock. “GLACIAL GROOVES STATE MEMORIAL.” It was as if a giant had drawn his fingers through an acre of soft butter. The grooves were parallel. They were larger than the gutters of bowling lanes. Aggregately, they suggested the fluted shafts of Greek columns. Their compass orientation .was n01theast-southwest -the established glide path of the moving ice. Nowhere had we seen or would we see more emphatic evidence of continental glaciation, with the obvious exception of the Great Lakes themselves. “If you were to hydraulically flush northern Ohio-wash off the soil from the bedrock-you’d see a hell of a lot of these grooves,” Anita said. “In several hundred years, these won’t be here. Limestone is soft enough to be grooved and hard enough to resist weather for a few hundred years. In shale, grooves like these would go quickly. The ice, carrying boulders in its underside-carrying those amphibolites and red jaspers in the people’s houses-tore the hell out of this island. When Agassiz saw things like this, he went bananas.” There have been kantoor per uur amsterdam glacial geologists, even in the late twentieth century, who have believed that such impressive grooves were gouged by boulders rolling in the Flood. Exceptions notwithstanding, Louis Agassiz’s theory of continental glaciation, like the theory of plate tectonics, achieved with extraordinary swiftness its general acceptance in the world. As Thomas Kuhn has demonstrated in The Structure of Scientific Revolutions, when a novel theory becomes relatively established it defines the patterns of amplifying research for many years and even centuries-until a new theory comes along to overturn the old, until an Einstein appears, outreaching the principles of Newton. Conceivably, the theory of plate tectonics will one day experience a general reformation.

Cambrian sandstone

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Some remnant Cambrian sandstone formed a blister in the valley. The interstate drifted around it in a westerly way and toward the foot of still another endless mountain-Bald Eagle, the last ridge of the deformed Appalachians. After the Cambrian sandstone, the Ordovician dolomite, there was Silurian quartzite in the gap that broke through the mountain. Its strata dipped steeply west. The rock had bent again, and again we were moving upward through history. Now, though, the dip of the strata would reverse no more. In a dozen miles of ever younger rock, we climbed through the Paleozoic era almost from beginning to end. We went up through time at least three hundred million years and up through the country more than a co-working space almere thousand vertical feet, the last ten miles uphill all the way, from Bald Eagle Creek to Snow Shoe, Pennsylvania-the longest steady grade on I-80 east of Utah-while light, wind-driven snow began to fall. We had come to the end of the physiographic province of the folded-and-faulted mountains, and the long ascent recapitulated Paleozoic history from the clean sands of the pre-tectonic sea to the dense twilight of Carboniferous swamps. We came up through the debris of three cordilleras, through repetitive sandstones and paper shales-Silurian paper shales, Devonian paper shales, Mississippian paper shales-crumbling on their shelves like acid-paper books in libraries. The shales were so incompetent that they would long since have avalanched and buried the highway had they not been benched-terraced in the manner of Machu Picchu. In other roadcuts, Catskill Delta sandstones, beet-red and competent, were sheer. We had gone through enough hard co-working space amsterdam ridges and soft valleys for me not just to sense but to see the Paleozoic pageant repeatedly played in the rock. For all the great deformity and complexity, the mountains now gone had left patterns behind. The land rising and falling, the sea receding and transgressing, the ancestral rivers losing power through time had not just obliterated much of what went before but had always imposed new scenes, and while I, for one, could not hold so many hundreds of pictures well related in my mind I felt assured beyond doubt that we were moving through more than chaos. The strata at the foot of the ten-mile hill had been nearly vertical. Gradually, through the long climb, they levelled out. They leaned backward, relaxed, one degree every two million years, until in the end they were Rat-at which moment the interstate left the deformed Appalachians and itself became level on the Allegheny Plateau.

North America

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Anita said, choosing North America’s most eminent example, “The Gulf of Mexico is a big geosyncline, if you want. The big birdfoot delta of the Mississippi River is one hell of a sedimentary pile. Drill twenty-two thousand feet down and you’re still in the Eocene. The crust will take about forty thousand feet of sediment-that’s the elastic limit. Then it regurgitates the sediment, which begins to rebound. The sediment is also heated up, melted. Water, gas, and oil come out of the rock. Sedimentary layers move up with thermal drives as well as with isostasy. Sedimentary layers also move laterally, and are thus thrust sheets. In Cambra-Ordovician time, fifty million years or so before the Taconic mountains came up, the continent was to the west of co-working space nijmegen us here, the coastline was in central Ohio, and to the east of us, where the Atlantic shelf is now, stood an island arc like Japan. There are volcaniclastic sediments of that age from Newfoundland to Georgia-just about the length of Japan. The present coast of Asia is the Ohio coastline in that story. Picture the sediment that is pouring off the Japanese islands into the Sea of Japan. The Martinsburg slates were shed not from the continent-not from Ohio-but mainly from the east, from the island arc offshore. You pile up forty thousand feet of sediment and it pops. The Martinsburg popped. The Taconic mountains came up. Once the process starts, it keeps itself going. You push up a mountain range, erode it into the west. The material depresses the crust. It is low-density material and it is brought down into the regime of high-density material. When enough has been piled on, the low-density material comes back up. That is how orogenic waves co-working space arnhem propagate themselves, each mountain mass being cannibalized to produce a new mountain mass to the west. But I still don’t know what started the process.” Historical geologists, in the olden days, pieced together that narrative. Economic geologists, in their pragmatic way, cared less. In describing the minable Martinsburg-the blue-gray true unfading slate-C. H. Behre, Jr., wrote in i933, “Sedimentary rocks are often compressed from the sides through what may be loosely described as shrinking of the crust of the earth; how this shrinking is brought about is, for the present purpose, beside the point. It has the wellrecognized effect, however, that layers or bedding planes are wrinkled or thrown into ‘folds.’ “

The peneplain

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Until about i970, the picture in vogue of the early Cenozoic American East was of a vast peneplain, a flat world of scant relief, with oxbowed meandering rivers heading almost nowhere. The assault of water on the ancestral mountains was thought to have worn down the whole topography close to sea level. The peneplain then rose up, according to the hypothesis, and rivers dissected it, flushing out the soft rock and leaving hard rock high, in the form of remarkably level ridges-as flat as the peneplain, of which they were thought to be remnants. Where the rivers of the peneplain had flowed across the tops of buried ridges, they cut down through them as the ridges came up-making gaps. That was the history as it was taught for three-quarters of a century. It was known as the hypothesis of the Schooley Peneplain, after co-working space almere Schooley Mountain, in New Jersey, which looks like an aircraft carrier. The Schooley Peneplain is out of vogue. It is an emeritus idea. It has been replaced by a story out of steady-state physics having to do with the relationship of level ridgelines to certain degrees of slope. A graduate student once remarked to me that old hypotheses never really die. He said they’re like dormant volcanoes.
Under the carbonate valleys and quilted farms, the rock was buried from view. The beauty of the fields against steep-rising forests, the shimmer of April green, was not doing much for Anita. She was in need of a lithic fix. Her fingers tapped the wheel. She reminded me of a white-water fanatic on a meandering stretch of flat river. “No wonder I never did geology in this part of Pennsylvania,” she said again. It had co-working space amsterdam been a long time between rocks. “I’d really like to go to Iran someday,” she went on, desperately. “The Zagros Mountains are another classic fold-and-thrust belt. The thing about the Zagros is that there’s no vegetation. You can see everything. They’re a hundred per cent outcrop.”

The plate-tectonics

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“The plate-tectonics people have certain set patterns that they expect to see,” Anita said. “They kind of lock themselves in. If something doesn’t fit the theory, they’ll find some sort of reason. They’ll say that something is missing, or that it was subducted, or that it has not yet been found in the subsurface. They make things fit.” “Do you believe that ocean crust is subducted into trenches, that it melts and then comes up behind the trenches as volcanoes and island arcs?” I asked her. “That is straightforward,” she said. “And I have no doubt that one edge of the Pacific Plate is grinding northwest through California. What I object to is plate tectonics taken as absolute gospel. To stuff that I know about, it’s been overapplied-without attention to geologic details. It’s been misused terribly. It has misrepresented facts. It has oversimplified the world. The Atlantic spreading open I absolutely believe. How long it has been spreading open I don’t know. I don’t really believe that North America and South America were conference room almere up against one another. The whole Pacific margin is thrusting from west to east, but there is no continent colliding with it. I don’t see that plate tectonics explains all of these things. I think tectonics on continents is different from tectonics in oceans, and what works in oceans is often misapplied on land. As a result, there is less understanding of regional geology. The plate-tectonic model is so generalized and is used so widely that people do not get good regional pictures anymore. People come out of universities with Ph.D.s in plate tectonics and they couldn’t identify a sulphide deposit if they fell over it. Plate tectonics is not a practical science. It’s a lot of fun and games, but it’s not how you find oil. It’s a cop-out. It’s what you do when you don’t want to think.” Before the plate-tectonics revolution, back in the penumbra of the Old Geology, mountains (as has been noted) were thought to be driven upward from a deep-seated source known as a geosynclinea profound downwarp of the crust, a long trough below the sea, which conference room amsterdam sediments fell into. East of North America, for example, the muds that would become Martinsburg slates first became rock in a geosyncline. The great trough trended northeast, like the mountains it would produce.