Thrust-faulted areas

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If all the ocean crust is Jurassic, or younger, there’s a lot happening here onshore that is never preserved out there. It’s difficult to compare the two.” Anita said, “I believe in plate tectonics-just not in the way they’re perpetrating it for places like the East Coast. It shouldn’t be used as the immediate answer to every problem. That’s what I object to. Now that their suture zones have disappeared, people are going to microplates.” “They seem to be saying that you don’t have to see any order,” Leonard said. “Because it’s all chaos, and if it’s chaos why worry about it?” ‘What we try to do is pull the thrust plates apart and make them into some sort of recognizable geologic model,” Anita said. Leonard said, “You pull something apart to see what it might have been, not what you think it was in advance. It might have been a shelf, a basin. You work at it, and see what it was.” “The plate-tectonics boys conference room amsterdam make no attempt to do this, because they see no reason to,” Anita said. “There are too many pieces missing. Each existing piece is an entity unto itself. Everything is random pieces.” “Most people have never had an opportunity to work with thrust-faulted areas. We’ve lived with them all our lives. If we go along a fault system far enough, we can actually see the next thrust plate. Maybe I’ll have to go a hundred miles until I find out what it really looked like. You do that by making a model. You pull the thrusts apart and see what the country originally looked like. But until you’ve done that, and been faced with that problem, it’s natural to say, ‘God, these are so different. They could be conference room amsterdam zuidas microcontinents.’ You can reconstruct a large Rat piece out to the east as an original depositional basin. You can see volcanic terrane that was partly onshore, partly offshore. You can look at that as a basin, too, just sitting there, a continuous thing. You see the same thing from Georgia north. The Appalachian belts are almost continuous basins, showing different kinds of depositional patterns. They’re not exotic pieces.” “Not at all.” “Science is not a detached, impersonal thing. People will be influenced as much by someone who is a spellbinder as by someone with a good, logical story. It is spellbinding to say that these belts are exotic and were built through time by micro or macro pieces aggregated to the continent. But the fact that you’ve got seismic lines without any apparent suture lines makes you wonder what really happened. Where are those Devonian and Taconic sutures? Are they just not being recognized? Or are they in fact thrust plates?”

The fifteenhundred-foot thickness

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To put it another way, in the fifteenhundred-foot thickness of the Bloomsburg formation, there were five millimetres for each hundred and sixty years. The interstate, with its keloid configuration, was blasted into the Shawangunk quartzites, blasted into the redbeds of the Bloomsburg, along the New Jersey side. As if that was not enough for one water gap, it turned and crossed the river. In all the rock we had walked by, the rivers and streams that carried the material had been flowing west co-working space amsterdam and northwest. I looked over the bank at the inventive Delaware, going the other way. ”When did the Delaware River come into existence?” I asked Anita. She shrugged, and said, “Long ago.” I said, “Really.” She turned and looked back toward the great slot in the mountain, and said, “In the late Jurassic, maybe. Possibly the early Cretaceous. I can look it up. I didn’t pay much attention to that part of geology.” In round numbers, then, the age of the river was a hundred and fifty million years. The age of the Water Gap rock was four hundred million years. Another fifty million years before that, the Taconic mountains appeared. The river i50, the rock 400, the first ancestral mountains 450 million years before the present-these dates are so unwieldy that they might as well be off a Manchu calendar unless you sense the pace of co-working space amsterdam zuidas geologic change and draw an analogy between, say, a hundred million years of geology and one human century, with its upward-fining sequences, its laminations of events, its slow deteriorations and instant catastrophes. You see the rivers running east. Then you see mountains rise. Rivers run off them to the west. Mountains come up like waves. They crest, break, and spread themselves westward. When they are spent, there is an interval of time, and then again you see the rivers running eastward. You look over the shoulder of the painter and you see all that in the landscape. You see it if first you have seen it in the rock. The composition is almost infinitely less than the sum of its parts, the flickers and glimpses of a thousand million years.

Innumerable jigsaw puzzles

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They are like odd pieces from innumerable jigsaw puzzles. The rock column-a vertical representation of the crust at some point on the earth-holds a great deal of inferable history, too. But rock columns are generalized; they are atremble with hiatuses; and they depend in large part on well borings, which are shallow, and on three-dimensional seismic studies, which are new, and far between. To this day, in other words, there remains in geology plenty of room for the creative imagination. All tlrn more amazing is the extent to which the early geologists, who flexplek huren amsterdam travelled the Appalachians in the eighteen-twenties and thirties, not only catalogued the evident rock but also worked out stratigraphic relationships among various formations and began to see composite structure. Starting close up, with this rock type, tl1at mountain, this formation, that valley-with what they could see and know-they gradually began to form tentative regional pictures. Piece by piece over the next century and a half, they and their successors would put together logically sequential narratives. presenting the comprehensive histo1y of the mountain belt. As new evidence and insight came along, old logic sometimes fell into discard. When plate tectonics arrived, its revelations were embraced or accommodated but by no means universally accepted. The Appalachians, meanwhile, continued slowly to waste away. The debate about their origins did not. Observing the flexplek huren amsterdam zuidas valley scene, the gapped and distant ridgeline, Anita said that mountains in this region had come up and been worn down not once but a number of times: the Appalachians were the result of a series of pulses of mountain building, the last three of which had been spaced across two hundred and fifty million years -the Taconic Orogeny, the Acadian Orogeny, and the Alleghenian Orogeny. The first stirrings of the Taconic Orogeny began nearly five hundred million years ago.

Fire escapes

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We came to Broadway and Berry Street, and now she had before her for the first time in twenty-five years the old building where she had lived. It was a six-story cubical tenement, with so many fire escapes that it seemed to be faced more with iron than with the red Triassic stone. Anita looked at the building in silence. Usually quick to fill the air with words, she said nothing for long moments. Then she said, “It doesn’t look as bad as it did when I lived here.” She stared on at the building for a while before flexplek huren haarlem speaking again, and when she did speak the nervousness of the morning was completely gone from her voice. “It’s been sandblasted,” she said. “They’ve cleaned it up. They’ve put a new facing on the lower stories, and they’ve sandblasted the whole building. People are wrong. They’re wrong in what they tell me. This place looks cleaner than when I lived here. The whole neighborhood still looks all right. It hasn’t changed. I used to play stickball here in the street. This is my neighborhood. This is the same old neighborhood I grew up in. I’m not afraid of this. I’m getting my confidence up. I’m not afraid.” We moved along slowly from one block to another. A young woman crossed the street in front of us, pushing a baby carriage. “She’s wearing a wig, I promise you,” Anita said. “Her head may be shaved.” Singling out another woman among the heterogeneous people of the neighborhood, she said, “Look. See that woman with the turban? She has her hair covered on flexplek huren amsterdam wtc purpose. They’re Chassidic Jews. Their hair is shaved off or concealed so they will not be attractive to passing men.” There was a passing man with long curls hanging down either side of his head-in compliance with a dictum of the Pentateuch. “Just to be in the streets here is like stepping into the Middle Ages,” Anita said.

Basin and Range

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Tanya Atwater, a marine geologist who eventually joined the faculty of the Massachusetts Institute of Technology, was then a graduate student at the Scripps Institution of Oceanography. In a letter written to Allan Cox at Stanford, she re-creates the milieu of the time. “Seafloor spreading was a wonderful concept because it could explain so much of what we knew, but plate tectonics really set us free and flying. It gave us some firm rules so that we could predict what we should find in flexplek huren amsterdam unknown places ….F rom the moment the plate concept was introduced, the geometry of the San Andreas system was an obviously interesting example. The night Dan McKenzie and Bob Parker told me the idea, a bunch of us were drinking beer at the Little Bavaiia in La Jolla. Dan sketched it on a napkin. ‘Aha!’ said I, ‘but what about the Mendocino trend?’ ‘Easy!,’ and he showed me three plates. As simple as that! The simplicity and power of the geometry of those three plates captured my mind that night and has never let go since. It is a wondrous thing to have the random facts in one’s head suddenly fall into the slots of an orderly flexplek huren amsterdam zuidas framework.  It is like an explosion inside. That is what happened to me that night and that is what I often felt happen to me and to others as I was working out (and talking out) the geometry of the western U.S. … The best part of the plate business is that it has made us all start communicating. People who squeeze rocks and people who identify deep-ocean nannofossils and people who map faults in Montana suddenly all care about each other’s work I think I spend half my time just talking and listening to people from many fields, searching together for how it might all fit together. And when something does fall into place, there is that mental explosion and the wondrous excitement. I think the human brain must love order.” Deffeyes, meanwhile, had joined Shell before the excitement developed. Growing up in oil fields, he had grown to like them, to admire the skill and independence of the crews, the competent manner in which they lived with danger. “Like a bullfighter, you are careful. So danger is not an overwhelming risk But it is always there. And you can be crushed, burned, asphyxiated, destroyed by an explosion. A crew on a rig floor runs pipe in the hole with swift precision, and any piece of equipment can take your hand off just as fast.”

Reduced the earth

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Deffeyes said, “If you reduced the earth to the size of a baseball, you couldn’t feel that mountain. With a telephoto lens, you could convince someone it was Everest.” Even at this altitude, the air was scented powerfully with sage. There was coyote scat at our feet. In the dark, we drove back the way we had come, over the painted cattle guards and past jackrabbits dancing in the road, pitch-dark, and suddenly a Black Angus was there, standing broadside, middle of the road. With a scream of brakes, we stopped. The animal stood still, thinking, its eyes unmoving-a wall of beef. We moved slowly after that, and even more slowly when a white sphere materialized on our right in the moonless sky. It expanded some, like a cloud. Its light became so bright that zakelijke energie we stopped finally and got out and looked up in awe. A smaller object, also spherical, moved out from within the large one, possibly from behind it. There was a Saturn-like ring around the smaller sphere. It moved here and there beside the large one for a few minutes and then went back inside. The story would be all over the papers the following day. The Nevada State Journal would describe a “Mysterious Ball of Light” that had been reported by various people at least a hundred miles in every direction from the place where we had been. “By this time we decided to get the hell out of there,” a couple of hunters reported, “and hopped in our pickup and took off. As we looked back at it, we saw a smaller craft come out of the right lower comer. This smaller craft had a dome in the middle of it and two wings on either side, but the whole thing was oval-shaped.” Someone else had said, “I thought it was an optical illusion at zakelijke energie vergelijken first, but it just kept coming closer and closer so that I could see it wasn’t an illusion. Then something started coming out of the side of it. It looked like a star, and then a ring formed around it. A kind of ring like you’d see around Saturn. It didn’t make any noises, and then it vanished.”

Seven hundred and fifty million years

Afbeeldingsresultaat voor site:ilocate.nl

In this adjustment, a day equals something like seven hundred and fifty million years, and thus “all day Monday and until Tuesday noon creation was busy getting the earth going.” Life began Tuesday noon, and “the beautiful, organic wholeness of it” developed over the next four days. “At 4 P.M. Saturday, the big reptiles came on. Five hours later, when the redwoods appeared, there were no more big reptiles. At three minutes before midnight, the human race appeared. At one-fourth of a second before midnight, Christ arrived. At one-fortieth of a second before midnight, the Industrial Revolution began. We are surrounded with people zakelijke energie who think that what we have been doing for that one-fortieth of a second can go on indefinitely. They are considered normal, but they are stark raving mad.” Brower holds up a photograph of the world -blue, green, and swirling white. “This is the sudden insight from Apollo,” he says. “There it is. That’s all. We see through the eyes of the astronauts how fragile our life really is.” Brower has computed that we are driving through the earth’s resources at a rate comparable to an automobile going a hundred and twenty-eight miles an hour-and he says that we are accelerating. In like manner, geologists will sometimes use the calendar year as a unit to represent the time scale, and in such terms the Precambrian runs from New Year’s Day until well after Halloween. Dinosaurs appear in the middle of December and are gone the zakelijke energie vergelijken day after Christmas. The last ice sheet melts on December 31st at one minute before midnight, and the Roman Empire lasts five seconds. With your arms spread wide again to represent all time on earth, look at one hand with its line of life. The Cambrian begins in the wrist, and the Permian Extinction is at the outer end of the palm. All of the Cenozoic is in a fingerprint, and in a single stroke with a mediumgrained nail file you could eradicate human history. Geologists live with the geologic scale. Individually, they may or may not be alarmed by the rate of exploitation of the things they discover, but, like the environmentalists, they use these repetitive analogies to place the human record in perspective-to see the Age of Reflection, the last few thousand years, as a small bright sparkle at the end of time.

Olympic Games

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From the high ridges right down to the level of the road, there was snow all over the Ruby Mountains. “Ugh,” said Deffeyes-his comment on the snow. “Spoken like a skier,” I said. He said, ‘Tm a retired skier.” 1 He skied for the School of Mines. In other Rocky Mountain colleges and universities at the time, the best skiers in the United States were duly enrolled and trying to look scholarly and masquerading as amateurs to polish their credentials for the i952 Olympic Games. Deffeyes was outclassed even on his own team, but there came a day when a great whiteout sent the superstars sprawling on the mountain. Deffeyes’ tum for the slalom came late in the afternoon, and just as he was moving toward the gate the f hiteout turned to alpenglow, suddenly bringing into focus the well-Dmpacted snow. He shoved off, and was soon bombing. He was not hurting for weight even then. He went down the mountain like an object dropped from a zakelijke energie tower. In the end, his time placed him high among the ranking stars. Now, in the early evening, crossing Independence Valley, Deffeyes seemed scarcely to notice that the white summits of the Ruby Range-above eleven thousand feet, and the highest mountains in this part of the Great Basin-were themselves being reddened with alpenglow. He was musing aloud, for reasons unapparent to me, about the melting points of tin and lead. He was saying that as a general rule material will flow rather than fracture if it is hotter than half of its melting point measured from absolute zero. At room temperature, you can bend tin and lead. They are solid but they flow. Room temperature is more than halfway between absolute zero and the melting points of tin and lead. At room temperature, you cannot bend glass or cast iron. Room temperature is less than halfway from absolute zero to the melting points of iron and glass. “If you go down into the earth here to a depth that about equals the width of one of these fault blocks, the temperature is halfway between absolute zero and the melting point of the rock. The crust is brittle above that point and plastic below it. Where the brittleness ends is the bottom of the tilting fault block, which rests-floats, if you zakelijke energie vergelijken like-in the hot and plastic, slowly flowing lower crust and upper mantle. I think this is why the ranges are so rhythmic. The spacing between them seems to be governed by their depth-the depth of the cold brittle part of the crust. As you cross these valleys from one range to the next, you can sense how deep the blocks are.

The Great Basinin

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They are all parts of the suite that opened the Atlantic seaway. The story is very similar in the Great Basinin the West, in the Basin and Range. The earth is splitting apart there, quite possibly opening a seaway. It is not something that happened a couple of hundred million years ago. It only began in the Miocene, and it is going on today. What we are ldoking at here in New Jersey is not just some little geologic feature, like a zeolite crystal. This is the opening of the Atlantic. If you want to see happening right now what happened here two hundred million years ago, you can see it all in Nevada.”
Basin. Fault. Range. Basin. Fault. Range. A mile of relief between basin and range. Stillwater Range. Pleasant Valley. Tobin Range. Jersey Valley. Sonoma Range. Pumpernickel Valley. Shoshone Range. Reese River Valley. Pequop Mountains. Steptoe Valley. Ondographic rhythms of the Basin and Range. We are maybe forty miles off the interstate, in the Pleasant Valley basin, looking up at the Tobin Range. At the zakelijke energie vergelijken nine-thousand-foot level, there is a stratum of cloud against the shoulders of the mountains, hanging like a ring of Saturn. The summit of Mt. Tobin stands clear, above the cloud. When we crossed the range, we came through a ranch on the ridgeline where sheep were fenced around a running brook and bales of hay were bright green. Junipers in the mountains were thickly hung with berries, and the air was unadulterated gin. This country from afar is synopsized and dismissed as “desert” -the home of the coyote and the pocket mouse, the side-blotched lizard and the vagrant shrew, the MX rocket and the pallid bat. There are minks and river otters in the Basin and Range. There are deer and antelope, porcupines and zakelijke energie cougars, pelicans, cormorants, and common loons. There are Bonaparte’s gulls and marbled godwits, American coots and Virginia rails. Pheasants. Grouse. Sandhill cranes. Ferruginous hawks and flammulated owls. Snow geese. This Nevada terrain is not corrugated, like the folded Appalachians, like a tubal air mattress, like a rippled potato chip. This is not-in that compressive manner-a ridge-and-valley situation.

The oldest rock yet found on earth

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The oldest rock yet found on earth (630, 632, 648) has an age close to four billion years, some six hundred million years younger than the earth itself. After reaching back to the earliest beginnings ( 63031), the story turns around and comes forward through the Archean Eon, while island arcs accrete and small cratons form (631-33). At the end of the Archean, in the very general neighborhood of 2.5 billion years before the present, great and unrepeatable changes occur in the behavior of the earth, including the precipitation of banded iron and the beginning of modern plate tectonics (634). In the early Proterozoic Eon, seven small cratons collide, conjoin as the Canadian Shield (633, 636-38). Younger island arcs eventually drift in and dock against the shield, forming large parts of Nebraska and Colorado (638-45). These  zakelijke energie novel views into Precambrian eons are the result of advances in radiometric dating ( 645-50) and, among other things, the measurement and interpretation of magnetic and gravity anomalies (651-54), all of it anchored and restrained by well cores (654-56). More arcs accrete. A coastal plate boundary like the Andean margin of South America develops along what is now a northeasterly trend through New Mexico and Kansas (650-51). About halfway through the Proterozoic, a baffling series of great plutons (each analogous to the Sierra Nevada batholith of relatively modern times) perforates North America from one side to the other and is mysteriously unaccompanied by the building of mountains, as plutons generally are, almost by definition (652-53). A time line at i.1 billion years comes in from the eastern and western margins of the continent and converges in the active and growing Midcontinent Rift (657-58). When the spreading stops under Iowa, the granites of Pikes Peak almost unaccountably appear in Colorado, the last tectonic event in Precambrian North America (660). An editor from whose counsel I have benefitted since the early zakelijke energie vergelijken phases of this project is Sara Lippincott, of Pasadena, California, who left The New Yorker in 1993 in order to become a free-lance editor of books. When Sara lived in New York, her idea of a perfect vacation was to get in an airplane and visit Caltech.