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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.

Progressive changes

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We saw painted on a storm sewer a white blaze of the Appalachian Trail, which came down from the mountain in New Jersey, crossed the river on the interstate, and returned to the ridgetop on the Pennsylvania side. There were local names for the sides of the gap in the mountain. The Pennsylvania side was Mt. Minsi, the New Jersey side Mt. Tammany. The rock of the cliffs above us was cleanly bedded, stratified, and had been not only deposited but also deformed in the course of the eastern orogenies. Regionally, it had been pushed together like cloth on a table. The particular fragment of the particular fold that erosion had left as the sustaining rock of the co-working space almere mountain happened to be dipping to the northwest at an angle of some forty-five degrees. As we walked in that general direction, each upended layer was somewhat younger than the last, and each, in the evidence it held, did not so much suggest as record progressive changes in Silurian worlds. “The dip always points upsection, always points toward younger rocks,” Anita said. “You learn that the first day in Geology I.” “Do you ever get tired of teaching ignoramuses?” I asked her. She said, “I haven’t worked on this level since I don’t know when.” Near the road and the river, at the beginning of the outcrop, great boulders of talus had obscured the contact between the mountain quartzite and the underlying slate. To move on through the gap, traversing the interior of the mountain, was to walk from early to late Silurian time, to examine an assembly of rock that had formed between 435 and 410 million years before the present. The first and oldest co-working space amsterdam quartzite was conglomeratic. Its ingredients had lithified as pebbles and sand. Shouting to be heard, Anita said, “In those pebbles you can see a mountain storm. You can see the pebbles coming into a sandbar in a braided river. There is very little mud in this rock. The streams had a high enough gradient to be running fast and to carry the mud away. These sands and pebbles were coming off a mountain range, and it was young and high.”

Unemployment

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Fortunately, her husband was even less interested in the water resources of Louisiana than she was in the unemployment interviews. They decided they needed Ph.D.s to improve their chances of working somewhere else. They enrolled at Ohio State, and in eastern Pennsylvania took up the summer field work that led to their dissertations. They did geologic mapping and biostratigraphy among the ridges of the folded Appalachians-noting the directional trends of the various formations (the strike) and their angles of dip, along a narrow band of deformation from the flexplek huren almere Schuylkill Gap near Reading to the Delaware Water Gap, and on toward the elbow of the Delaware River where Pennsylvania, New Jersey, and New York conjoin. The most recent ice sheet had reached the Water Gap-where the downcutting Delaware River had sawed a mountain in two-and had filled the gap, and even overtopped the mountain, and then had stopped advancing. So the country of their dissertations was filled with fossil tundra, with kames and eskers, with periglacial boulders and the beds of vanished lakes, with erratics from the Adirondacks, with a vast imposition of terminal moraine. Like the outwash of Brooklyn and the tills of Indiana, this Pennsylvania countryside helped to give Anita her sophistication in glacial geology, which was consolidated at Ohio State, whose Institute of Polar Studies trains specialists in the field. Glacial evidence was not, however, what drew her particular attention. The Wisconsinan ice was flexplek huren amsterdam modem, in the long roll of time, in much the way that Edward VII is modem compared with a hominid skull. The ice melted back out of the Water Gap seventeen thousand years ago. Anita was more interested in certain stratigraphic sequences in rock that protruded through the glacial debris and had existed for several hundred million years. She would crush this rock, separate out certain of its components, and under a microscope at fifty to a hundred magnifications study its contained conodonts, hard fragments of the bodies of unknown marine creatures-hard as human teeth, and of the same material. At a hundred magnifications, some of them looked like wolf jaws, others like shark teeth, arrowheads, bits of serrated lizard spine-not unpleasing to the eye, with an asymmetrical, objet-trouve appeal.

Plate tectonics

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Her father was Russian, and his name in the old country was Herschel Litvak. In Brooklyn, he called himself Harry Fishman, and sometimes Harry Block. According to his daughter, English names meant nothing to Russian Jews in Brooklyn. She grew up Fishman and became in marriage Epstein and Harris, signing her geology with her various names and imparting some difficulty to flexplek huren nijmegen followers of her professional papers. With her permission, I will call her Anita, and let the rest of the baggage go. Straightforwardly, as a student, she went into geology because geology was a means of escaping the ghetto. “I knew that if I went into geology I would never have to live in New York City,” she once said to me. “It was a way to get out.” She was nineteen years old when she was graduated from Brooklyn College. She remembers how pleased and astounded she was to learn that she could be paid “for walking around in mountains.” Paid now by the United States Geological Survey, she has walked uncounted mountains. After the level farmlands of northwestern Ohio, the interstate climbed into surprising terrain-surprising enough to cause Anita to suspend her attack on plate tectonics. Hills appeared. They were steep in pitch. The country resembled New England, a confused and thus beautiful topography of forested ridges and natural lakes, stone fences, bunkers and bogs, cobbles and boulders under maples and oaks: Indiana. Rough and semi-mountainous, this corner of Indiana was giving the hummocky lie to the reputed flatness of the Middle West. Set firmly on the craton-the Stable Interior Craton, unstirring core of the continent-the whole of Middle America is structurally becalmed. Its flexplek huren arnhem basement is coated with layers of rock that are virtually flat and have never experienced folding, let alone upheaval. All the more exotic, then, were these abrupt disordered hills. Evidently superimposed, they almost seemed to have been created by the state legislature to relieve Indiana. Not until the nineteenth century did people figure out whence such terrain had come, and how and why. “Look close at those boulders and you’ll see a lot of strangers,” Anita remarked. “Red jasper conglomerates. Granite gneiss. Basalt. None of those are from anywhere near here. They’re Canadian. They have been transported hundreds of miles.”

The papers

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The papers themselves had straightforward scientific titles, some of which-perhaps only in the afterlight of their great effect -seem to resound with the magnitude of the subject: “History of Ocean Basins,” “Rises, Trenches, Great Faults, and Crustal Blocks,” “Sea-Floor Spreading and Continental Drift,” “Seismology and the New Global Tectonics.” From Berkeley, Princeton, San Diego, New York, Canberra, Cambridge (England), there were about twenty primal contributions which, taken together, can be said to have constituted the plate-tectonics revolution. Now flexplek huren almere plate tectonics is widely taken for granted. When I was in high school, there was essentially no television in America, and four years later television had replaced flypaper. When I was in high school, in the nineteen-forties, the term “plate tectonics” did not exist-albeit there was one remarkably prescient paragraph in our physical-geology textbook about the motions and mechanisms of continental drift. Today, children in schoolrooms just assume that the story being taught them is as old as the hills, and was told by God himself to their teacher in 4004 B.C. The story is that everything is moving, that the outlines of continents by and large have nothing to do with these motions, that “continental drift” is actually a misnomer, that only the world picture according to Marco Polo makes much sense in the old-time browns and greens and Rand McNally blues. The earth is at present divided into some twenty crustal segments called plates. Plate flexplek huren amsterdam boundaries miscellaneously run through continents, around continents, along the edges of continents, and down the middle of oceans. The plates are thin and rigid, like pieces of eggshell. In miles, sixty deep by nine thousand by eight thousand are the dimensions of the Pacific Plate. “Pacific Plate” is not synonymous with “Pacific Ocean,” which wholly or partly covers many other plates. There are virtually no landmasses associated with some plates-the Cocos Plate, the Nazca Plate. Some plates are almost entirely land-the Arabian Plate, the Iranian Plate, the Eurasian Plate, a large part of which used to be known as the (heaven help us) China Plate. (Jokes may be invisible to some geologists. Harry Hess, who in ig6o opened out the new story with his “History of Ocean Basins,” began it with these words:

Verbal gifts

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The least of his many verbal gifts was a slow-cooled lucidity, a sense of the revealing phrase, and his Illustrations of the Huttonian Theory of the Earth, published in i802, was the first fully clear and persuasive statement of what the theory was about. It is testimony to Playfair’s efficacity that the opposition stiffened. “According to the conclusions of Dr. Hutton, and of many other geologists, our continents are of indefinite antiquity, they have been peopled we know not how, and mankind are wholly unacquainted with their origin,” wrote the Calvinist geologist Jean Andre Deluc in i809. “According to my conclusions, drawn from the same source, that zakelijke energie of facts, our continents are of such small antiquity, that the memory of the revolution which gave them birth must still be preserved among men; and thus we are led to seek in the book of Genesis the record of the history of the human race from its origin. Can any object of importance superior to this be found throughout the circle of natural science?” As geologists built the time scale, their research and accumulating data imparted to Hutton’s theory an obviously increasing glow. And in the early eighteen-thirties Charles Lyell, who said in so many words that his mission in geology was “freeing the science from Moses,” gave Hutton’s theory and his sense of deep time their largest advance toward universality. In three volumes, he published a work whose full title was Principles of Geology, Being an Attempt to Explain the Former Changes of the Earth’s Suiface, by Reference to Causes Now in Operation. Lyell was so anti-neptunist, so anticatastrophist that he out-Huttoned Hutton both in manner and in form. He not only subscribed to the zakelijke energie vergelijken uniformitarian process-the topographical earth building and destroying and rebuilding itself through time-but was finicky in insisting that all processes had been going on at exactly the same rate through all ages. Principles of Geology was to be the most enduring and effective geological text ever published. The first volume was eighteen months off the press when H.M.S. Beagle set sail from Devonport with Charles Darwin aboard. “I had brought with me the first volume of Lyell’ s Principles of Geology, which I studied attentively; and the book was of the highest service to me in many ways.

A mineral system

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A theory is thus formed with regard to a mineral system. In this system, hard and solid bodies are to be formed from soft bodies, from loose or incoherent materials, collected together at the bottom of the sea; and the bottom of the ocean is to be made to change its place …t o be formed into land …. Having thus ascertained a regular system in which the present land of the globe had  zakelijke energie been first formed at the bottom of the ocean and then raised above the surface of the sea, a question naturally occurs with regard to time; what had been the space of time necessary for accomplishing this great work? … We shall be warranted in drawing the following conclusions; 1st, That it had required an indefinite space of time to have produced the land which now appears; 2dly, That an equal space had been employed upon the construction of that former land from whence the materials of the present came; Lastly, That there is presently laying at the bottom of the ocean the foundation of future land. . . .
As things appear from the perspective of the twentieth century, James Hutton in those readings became the founder of modern geology. As things appeared to Hutton at the time, he had constructed a theory that to him made eminent sense, he had put himself on the line by agreeing to confide it to the world at large, he had provoked not a few hornets into flight, and now-like the experimental physicists who would one day go off to check on Einstein by photographing the edges of solar eclipses-he had best do some additional travelling to see if he was right. As he would express all this in a chapter heading when he ultimately wrote his book, he zakelijke energie vergelijken needed to see his “Theory confirmed from Observations made on purpose to elucidate the Subject.” He went to Galloway. He went to Banffshire. He went to Saltcoats, Skelmorlie, Rumbling Bridge. He went to the Isle of Arran, the Isle of Man, Inchkeith Island in the Firth of Forth. His friend John Clerk sometimes went with him and made line drawings and watercolors of scenes that arrested Hutton’s attention. In ig68, a John Clerk with a name too old for Roman numerals found a leather portfolio at his Midlothian estate containing seventy of those drawings, among them some cross sections of mountains with granite cores.

Collapsed and condensed

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As the great clouds collapsed and condensed, they formed a compact rock in large part consisting of volcanic glass. It was so thick-as much as three hundred metres thick-that crystals formed slowly in the cooling glass. “When you bury a countryside in that much rock so hot it welds, that is the ultimate environmental catastrophe,” Deffeyes remarked. ‘Tm glad there hasn’t been one recently.” The province, stung like that, sat still here for twenty-two million years, with volcanism continuing only on its periphery, while erosion worked on the tuff, making draws and gulches, modest valleys and unspectacular hills, but not extensively altering the essentially level plain. There was no repetition of the foaming, frothing outpourings that had completely changed many tens of thousands of square miles of the face of the earth, but so  zakelijke energie much disturbance arising from and within the underlying earth was obviously precursive of disturbances to follow, when the plains of welded tuff and some thousands of feet below them began to rift into crustal blocks and become the Basin and Range. The basins filled immediately with water, and life came into the lakes. “Late-Miocene fossils are the earliest we have wherever we have found fossils in those lakebeds,” Deffeyes said. “So Basin and Range faulting can be dated to the late Miocene-about eight million years ago.” Gradually, as the rain shadow lengthened, the lakes “turned chemical”-became saline or alkaline (bitter)-and eventually they d1ied up. There are basalt flows in the Basin and Range that are also post-Miocene-lavas that poured out on the surface well after the block faulting had begun, like the Watchungs of New Jersey. There are ruins of cinder cones-evidence of fairly recent local action-and, in the basins and on the ranges, widespread falls of light ash from volcanoes beyond the province. You see, too, the stream deltas, shoreline terraces, and wave-cut cliffs of big lakes that came into the Great Basin after Pleistocene glaciation began. The change in world climate that made ice in the north temporarily preempted the rain shadow and dropped into the Great Basin torrents from the sky. In a region where evaporation had greatly exceeded precipitation, the zakelijke energie vergelijken reverse was now the case, and the big lakes in time connected the basins and made islands of the ranges-Lake Manlius (its bed is now, in part, Death Valley); Lake Lahontan, near Reno (its bed is now, in part, the Humboldt and Carson sinks); and Lake Bonneville. Lake Bonneville grew until it was the size of Lake Erie.

The Sierra

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The Sierra is rising on its east side and is hinged on the west, so the slope is long to the Sacramento Valley-the physiographic province of the Great Valley-flat and sea-level and utterly incongruous within its flanking mountains. It was not eroded out in the normal way of valleys. Mountains came up around it. Across the fertile flatland, beyond the avocados, stand the Coast Ranges, the ultimate province of the present, the berm of the ocean-the Coast Ranges, with their dry and straw-brown Spanish demeanor, their shadows of the live oaks on the ground. If you zakelijke energie vergelijken were to make that trip in the Triassic-New York to San Francisco, Interstate 80, say roughly at the end of Triassic timeyou would move west from the nonexistent Hudson River with the Palisades Sill ten thousand feet down. The motions that will open the Atlantic are well under way (as things appear in present theory), but the brine has not yet come in. Behind you, in fact, where the ocean will be, are several thousand miles of land-a contiguous landmass, fragments of which will be Africa, Antarctica, India, Australia. You cross the Newark Basin. It is for the most part filled with red mud. In the mud are tracks that seem to have been made by a twoton newt. You come to a long, low, north-south-trending, black, steaming hill. It is a Row of lava that has come out over the mud and has cooled quickly in the air to form the dense smooth textures of basalt. Someday, towns and landmarks of this extruded hill will in one way or another take from it their names: Montclair, Mountainside, Great Notch, Glen Ridge. You top the rise, and now you can see across the rest of the basin to the Border Fault, and-where Whippany and Parsippany will be, some thirty miles west of New York-there is a mountain front perhaps seven thousand feet high. You climb this range and see more and more mountains beyond, and they are the folded-and-faulted Appalachians, but middle-aged and a little rough still at zakelijke energie the edges, not caterpillar furry and worndown smooth. Numbers do not seem to work well with regard to deep time. Any number above a couple of thousand years-fifty thousand, fifty million-will with nearly equal effect awe the imagination to the point of paralysis.

Een lastig dilemma

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In het oude Babylon klommen mensen die voor een lastig dilemma stonden in een donkere nacht op het dak van de plaatselijke tempel om de hemel te observeren. De Babyloniërs geloofden dat de sterren hun lot bepaalden en hun toekomst voorspelden. Ze keken naar de sterren om te beslissen of ze moesten trouwen, de akkers moesten omploegen of een oorlog moesten beginnen. Hun filosofische geloofsopvattingen werden vertaald naar uiterst praktische handelingen. Geloven met een heilig boek, zoals het jodendom en het christendom, vertelden een ander verhaal: ‘De sterren liegen. God, die de sterren heeft geschapen, heeft de volledige waarheid onthuld in de Bijbel. Laat de sterren dus voor wat ze zijn en lees de Bijbel!’ Ook dat was een praktische aanbeveling. Als mensen niet wisten met wie ze moesten trouwen, wat voor werk ze moesten gaan doen en of ze een oorlog moesten beginnen, lazen ze de Bijbel en volgden de adviezen daarin op. Toen kwamen de humanisten, met weer een compleet nieuw verhaal: ‘De mens heeft God uitgevonden, de Bijbel geschreven en  zakelijke energie die vervolgens op duizend verschillende manieren geïnterpreteerd. Mensen zijn dus zelf de bron van alle waarheid. Je kunt de Bijbel wel lezen als een inspirerend literair kunstwerk, maar het hoeft niet. Als je voor een dilemma staat, luister dan naar jezelf en volg de stem van je innerlijk.’ Daarbij gaf het humanisme gedetailleerde praktische instructies over het luisteren naar jezelf en beval het technieken aan als naar zonsondergangen kijken, Goethe lezen, een dagboek bijhouden, diepe gesprekken voeren met goede vrienden en democratische verkiezingen houden. Eeuwenlang volgden ook wetenschappers deze humanistische richtlijnen. Als natuurkundigen onzeker waren over een eventueel huwelijk keken ze ook naar zonsondergangen en probeerden ze in contact te komen met zichzelf. Als scheikundigen nadachten over een problematische nieuwe baan, schreven ze ook in hun dagboek en voerden ze lange gesprekken met goede vrienden. Als biologen twijfelden tussen oorlog voeren of de vrede tekenen, gingen ze ook stemmen bij democratische verkiezingen. Als hersenwetenschappers boeken schreven over hun verbluffende ontdekkingen, zetten ze vaak een inspirerend citaat van Goethe op de eerste bladzijde. Dat was de basis voor de moderne alliantie tussen wetenschap en zakelijke energie vergelijken humanisme, die de wankele balans tussen het moderne yang en het moderne yin in stand hield -tussen rede en emotie, tussen het laboratorium en het museum, tussen de lopende band en de supermarkt.