The Brevard Zone

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I remembered Leonard Harris-one day at their home in Laurel, Maryland-saying, “The Brevard Zone is the sort of fault you would see in any thrust belt. With the plate-tectonic model, anybody can write a history of an area without having been there. These people have no way to evaluate what they’re doing. They just make up stories.” “Plate-tectonic interpretations often start where data stop,” Anita had said. “These people will just float microplates around. If the West is made of microplates, where the hell was the landmass that produced the pieces?” “They want to be science-fiction writers,” Leonard said. “That’s what they want to do. They really look at it in a science-fiction mode. I have never been able to do that. If you don’t know what caused something, you don’t know; and that’s the way it is.” “Yeah, but it’s a much more romantic way to look at things,” she said. “And it certainly does tum students on.” “People love it.” “It allows them to play all kinds of games without the necessity and painstaking dogwork of gathering facts. It allows them to write papers conference room amsterdam without killing themselves getting data.”
People want the science-fiction story. It’s easier to believe that pieces of the world move than it is to see a sand grain move. The principal problem about interpreting the Appalachians is that there have been no available subsurface data in the Blue Ridge and Piedmont. All interpretations, up until i979, were based on what people thought was a rooted system. Their ideas were based on offshore data, where they had 3-D-you know, seismic data, magnetic data -and these data were more or less applied onshore. The concepts were developed from the ocean to the land. Now that we are beginning to get subsurface data on land, we are testing their concepts. A lot of what people have been saying is not hanging together. Some of what they have said has hung together.” I said to them, “One would gather from the seismic lines that for a continent-to-continent collision you’d have to go pretty far east to find the suture.” “I don’t think you can go far east enough,” Anita said. “The oceanic basin is out there.” “When you start working on the shore and you look offshore, you’ve got an immediate problem,” Leonard said. “They tell us that the oldest ocean crust that has ever been found is Jurassic. Onshore, we conference room amsterdam have everything that’s ever been built-from the Precambrian on up. We have a continuum. We have something that has been preserved much longer. We have rock that is nearly four billion years old. So we have a problem relating.

The narrow floodplain

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There was a fine view. On the narrow floodplain and river terraces of New Jersey, where I-80 would be, there were cultivated fields and split-rail fences, corn shocks in autumn, fresh furrows in spring. Anita and I came to the end of the Bloomsburg, or as far as it went in the outcrops of the gap. “These are coarse basal sands,” she said of one final layer. “They were deposited in channels and point bars through lateral accretion as the stream meandered.” In all, there were fifteen hundred feet of the formation, reporting the disintegration of high Silurian worlds. Ten or twelve years after the tum of the century, a Bergdoll touring car pulled into the porte cochere of Water Gap House and the chauffeur stepped out, leaving co-working space maastricht Theodore Roosevelt alone in the open back while a photograph arrested his inscrutable face, his light linen suit, his ten-gallon paunch and matching hat. This must have been a high moment for the resort community, but just as Teddy (1858-1919) was in his emeritus years, so, in a sense, was the Water Gap. A fickling clientele preferred Niagaras with falls. An intercity trolley had been added to the scene. Two miles downstream-in what had been George Inness’s favorite foreground-was a new railroad bridge that looked like a Roman aqueduct. Rails penetrated the gap on both sides of the river. There was a golf course-dramatic in its glacial variations on precipitous tills pushed by the ice up the side of the broken mountain-where Walter Hagen, in 1926, won the Eastern Open Championship. Soon thereafter, the tournament was played for the last time. Walter Hagen was not coming back, and neither was the nineteenth century. The perennial Philadelphians were now in Maine. In 1931, Kittatinny House burned up co-working space amsterdam like a signal fire. Freight trains wailed as they rumbled past the embers. In 1960 came the interstate-a hundred and sixty years after the first wagon road. As a unit of earth history, a hundred and sixty years could not be said to be exactly nothing-although, in the gradually accumulated red rock beside the river, ninety-four thousand such units were represented.

The early Appalachian geologists

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The early Appalachian geologists, in their horse-drawn buggies, their suits and ties, developed a sense of physiography that tuned them to the land, and when they saw long sugarloaf hills they had learned to suspect that there was dolomite within, and when they looked up at coxcomb ridges they felt the presence of Cambrian sandstones, and of Cambrian shales in the valleys beyond. The higher, harder ridges would be thick, Silurian quartzites, more often than not, while flourishing green lowlands with protruding ribs of rock would owe their shape and their fertility to limestones assembled in Ordovician seas. There were knolls in the valleys. Inside the knolls were shales. Shale breaks up easily but flexplek huren maastricht will not dissolve like limestone, so the shales became blisters in the limestone valleys. Of the two carbonate rocks, limestone is a good deal more soluble than dolomite, and that was why dolomite would retain itself in sugarloaves above the limestone valleys. Once the early geologists had developed this sense of the substrate, they shook the reins and moved with dispatch, filling in the first American geologic maps with a general accuracy that is impressive still. Identifying what is there scarcely describes what happened to put it there, however. The history of the earth may be written in rock, but history is not coherent on a geologic map, which shows a region’s uppermost formations in present time, while indicating little of what lies farther down and less of what is gone from above. At a given place-a given latitude and longitude-the appearance of the world will have changed too often to be recorded in a single picture, will have been, say, at one time below fresh water, at another under brine, will have been flexplek huren amsterdam mountainous country, a quiet plain, equatorial desert, an arctic coast, a coal swamp, and a river delta, all in one Zip Code. These scenes are discernible in, among other things, the sedimentary characteristics of rock, in its chemical composition, magnetic components, interior color, hardness, fossils, and igneous, metamorphic, or depositional age. But as parts of the historical narrative these items of evidence are just phrases and clauses, often wildly disjunct.

Distant transport

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But such distant transport, while it characterizes continental ice sheets wherever they have moved, accounts for a low percentage of the rock in glacial drift. The glacier cuts and fills. Continuously, it plucks up material and sets it down, plucks it up, sets it down. It taketh away, and then it giveth. A diamond may travel from Quebec to Indiana, some dolomite from Lake George to the sea, but most of what is lifted is dropped nearby-boulders from New Jersey in Prospect Park. “Glacial geology is simple to deal with,” Anita said, “because so much of what the glacier created is preserved. Also, you can go places and see the flexplek huren breda same processes working. You can go to Antarctica and see continental glaciation. There’s alpine glaciation in Alaska.” This warm clear summer day was now approaching noon, and Prospect Park was quiet and unpeopled. It was all but deserted. Anita as a child had come here often. She remembered people and picnics everywhere she looked, none of this ominous silence. “I suppose it isn’t safe,” she said, and we moved on toward Williamsburg. As we drew close, she became even more obviously nervous. “They tell me it’s just the worst slum in the world now,” she said. “I don’t know if I should tell you to roll up all the windows and lock the doors.” “We would die of the heat.” “This is a completely unnatural place,” she went on. “It’s a totally artificial environment. Cockroaches, rats, human beings, and pigeons are all that survive. At Brooklyn College, my instructors had difficulty relating geology to the lives of people in this artificial world. In the winter, maybe you froze your ass off waiting for the subway. Maybe that was a way to begin discussing glaciation. In the city, let me tell you, no one knows from geology.” We flexplek huren haarlem went first to her high school. It appeared to be abandoned and was not. It was a besooted fortress with battlements. Inside were tall cool hallways that smelled of polish and belied the forbidding exterior. She had walked the halls four years with A’s on her report cards and been graduated with high distinction at the age of fifteen. We went to P.S. 37, her grade school.

How science works

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That is how science works. Ideas range from the solidly accepted to the literally half-baked-those in the process of forming, the sorts of things about which people call each other up in the middle of the night. All science involves speculation, and few sciences include as much speculation as geology. Is the Delaware Water Gap the outlet of a huge lake all other traces of which have since disappeared? A geomorphologist will tell you that, in principle, the idea is O.K. You have to deal with partial information. In oil drilling, you had better be ready to act shrewdly on partial information. Do physicists do that? Hell, no. They want flexplek huren maastricht to have it to seven decimal places on their Hewlett-Packards. The geologist has to choose the course of action with the best statistical chance. As a result, the style of geology is full of inferences, and they change. No one has ever seen a geosyncline. No one has ever seen the welding of tuff. No one has ever seen a granite batholith intrude.” Since I was digging his sample pits, I felt enfranchised to remark on what I took to be the literary timbre of his science. “There’s an essential difference,” he said. “The authors of literary works may not have intended all the subtleties, complexities, undertones, and overtones that are attributed to them by critics and by students writing doctoral theses.” “That is what God says about geologists,” I told him, chipping into tlrn sediment with his broken shovel. “You may recall Archelaus’s explanation of earthquakes,” he said cryptically. “Earthquakes were caused by air trapped in underground caves. It shook the earth in its effort to escape. Everyone knew flexplek huren amsterdam then that the earth was flatulent.” Deffeyes said he had asked his friend Jason Morgan-whose paper “Rises, Trenches, Great Faults, and Crustal Blocks” defined the boundaries of the plates-what he was going to do for an encore. Morgan said he didn’t know, but possibly the most exciting thing to do next would be to prove the theory wrong. That would be a reversal comparable to the debunking of Genesis. I remembered Eldridge Moores, of the University of California at Davis, telling me what it had been like to be in graduate school at the height of the plate-tectonics revolution, and how he had imagined that the fervor and causal excitement of it was something like landing on Guadalcanal in the middle of the action of “a noble war.”

Five-pound ingot

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For a short while, he would have a five-pound ingot of raw silver on the floor, propping open the door. When he was finished with his pond, he would withdraw the cyanide and turn it into a marketable compound known as Prussian blue. He would cover his pond with dirt and sow it with crested wheat. And now, :finishing up his sampling at the mine in the mountains, he filled a large burlap bag with ore he would take home to improve his technique of extraction. The smaller samples he had taken were for assays of silver in various parts of the slope. ‘Tm nothing but a ragpicker,” he said. “A scavenger armed zakelijke energie with a fortythousand-dollar X-ray machine.” The wind picked up another cloud of dust off the dump and blew it into his face. He mooed. “That may feel like dirt to you, but it feels like money to me,” he said. “How much money would you say that felt like?” I asked him. He took out a Magic Marker and began to do metric conversions, geometry, and aiithmetic on the side of a new canvas bag. “Well, this section of the dump is at least fifteen thousand cubic metres,” he said. ‘That is the most conservative figure. At two hundred dollars a ton, that works out to about three million dollars, left here in the side of the hill.” “What are those red stakes up there?” “Somebody seems to think they’re finding new ore. I’m interested in the old stuff, down here.” “If you’ve got good silver in those bags, what zakelijke energie vergelijken about Eocene? What if they decide they still own you? What if they go to the sheriff?” “Eocene doesn’t own me, and Eocene doesn’t own the contents of my head. The law has long since decided that. But if anybody comes after me I want you to go to jail cheerfully rather than surrender your notes.”

Eighteenth-century geology

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At the other end of the scale is the Holocene, the past ten thousand years, also called the Recent-Cro-Magnon brooding beside the melting ice. (The Primitive and Secondary eras of eighteenth-century geology are long since gone from the vocabulary, but oddly enough the Tertiary remains. The term, which is in general use, embraces nearly all of the Cenozoic, from the Cretaceous Extinction to the end of the Pliocene, while the relatively short time that follows-the Pleistocene plus the Holocene-has come to be called the Quaternary. The moraines left by ice sheets are Quaternary, as are the uppermost zakelijke energie basin fillings in the Basin and Range.) It was at some moment in the Pleistocene that humanity crossed what the geologist-theologian Pierre Teilhard de Chardin called the Threshold of Reflection, when something in people “turned back on itself and so to speak took an infinite leap forward. Outwardly, almost nothing in the organs had changed. But in depth, a great revolution had taken place: consciousness was now leaping and boiling in a space of super-sensory relationships and representations; and simultaneously consciousness was capable of perceiving itself in the concentrated simplicity of its faculties. And all this happened for the first time.” Friars of another sort-evangelists of the environmental movement-have often made use of the geologic time scale to place in perspective that great “leap forward” and to suggest what our reflective capacities may have meant to Mother Earth. David Brower, for example, the founder of Friends of the Earth and emeritus hero of the Sierra Club, has tirelessly travelled the United States delivering what he himself refers to as “the sermon,” and sooner or later in every zakelijke energie vergelijken talk he invites his listeners to consider the six days of Genesis as a figure of speech for what has in fact been four and a half billion years.

A hundred per cent

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I once dreamed about a great fire that broke out at night at Nasser Aftab’s House of Carpets. In Aftab’s showroom under the queen-post trusses were layer upon layer and pile after pile of shags and broadlooms, hooks and throws, para-Persians and polyesters. The intense and shrivelling heat consumed or melted most of what was there. The roof gave way. It was a night of cyclonic winds, stabs of unseasonal lightning. Flaming debris fell on the carpets. Layers of ash descended, alighted, swirled in the wind, and drifted. Molten polyester hardened on the cellar stairs. Almost simultaneously there occurred a major zakelijke energie accident in the ice-cream factory next door. As yet no people had arrived. Dead of night. Distant city. And before long the west wall of the House of Carpets fell in under the pressure and weight of a broad, braided ooze of six admixing flavors, which slowly entered Nasser Aftab’s showroom and folded and double-folded and covered what was left of his carpets, moving them, as well, some distance across the room. Snow began to fall. It turned to sleet, and soon to freezing rain. In heavy winds under clearirlg skies, the temperature fell to six below zero. Celsius. Representatives of two warring insurance companies showed up just in front of the fire engines. The insurance companies needed to know precisely what had happened, and in what order, and to what extent it wa Aftab’s fault. If not a hundred per cent, then to what extent was it the ice-cream factory’s fault? And how much fault must be-regrettably-assigned to God? The problem was obviously too tough for the Chicken Valley Police Department, or, for that matter, for any orfunary detective. It was a problem, naturally, for a field geologist. [One shuffled in zakelijke energie vergelijken eventually. Scratched-up boots. A puzzled look. He picked up bits of wall and ceiling, looked under the carpets, tasted the ice cream. He felt the risers of the cellar stairs. Looking up, He told Hartford everything it wanted to know. For him this was so simple it was a five-minute job.

Hook Mountain

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There were oaks and maples on top of Hook Mountain, and, in the wall of the roadcut, basal rosettes of woolly mullein, growing in the rock. The Romans drenched stalks of mullein with suet and used them for funeral torches. American Indians taught the early pioneers to use the long flannel leaves of this plant as innersoles. Only three miles west of us was the Border Fault, where the basin had touched the range, where the stubby remnants of the fault scarp are now under glacial debris. Deffeyes said that the displacement along the fault-the eventual difference between two points that had been adjacent when the faulting began-exceedej fifteen thousand feet. Of course, this happened over several millions of years, and the mountains fronting the basin were all the while eroding, so they were never anything like fifteen thousand zakelijke energie vergelijken feet high. Generally, though, in the late Triassic, there would have been about a rrlile of difference, a mile of relief, between basin and range. In flash floods, boulders came raining off the mountains and piled in fans at the edge of the basin, ultimately to be filled in with sands and muds and to form conglomerate, New Jersey’s so-called Hamber Creek Conglomerate-multicircled, polka-dotted headcheese1 rock, sometimes known as puddingstone. Here where the basin met the range, the sediments piled up so much that after all of the erosion of two hundred million years what remains is three miles hick. “I was in a bar once in Austin, Nevada,” Deffeyes said, “and there was a sudden torrential downpour. The bartender began nailing plywood over the door. I wondered why he was doing that, until boulders came tumbling down the main street of the town. When you start pulling a continent apart, you have a lot of consequences of the same event. Faulting produced this basin. Sediments filled it in. Pull things apart and you produce a surface vacancy, which is faulting, and a subsurface vacancy, which causes upwelling of hot mantlJ that intrudes as sills or comes out as lava flows. In the Old Geology, you might have seen a sill within the country rock and said, ‘Ah, the sill came much later.’ With the New Geology, you see that all this was happening more or less at one time. The continent was splitting apart and the ultimate event was the opening of the Atlantic. I( you look at the foldb elt in northwest Africa, you see the other side of the New Jersey story. The folding there is of the zakelijke energie same age as the Appalachians, and the subsequent faulting is Triassic. Put the two cohtinents together on a map and you will see what I mean. Fault bldcks like this one are still in evidence, but discontinuously, from rf:he Connecticut Valley to South Carolina.

Ocean-crustal rock

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Moores is an ophiolitologist, an expert on ocean-crustal rock, which asks or answers large questions when it is found detached and lying on continents. An introduction to the nature and complexity of ophiolites (476-5u) is followed by subflashbacks to Cyprus (5ll19) and Greece (519-26), where Moores has done research for decades and where transported rock of the ocean floor stands as mountains. With the exception of some veneer, this is not sedimentary rock derived from continents and laid down in the sea; this is igneous rock from magma chilled at ocean spreading centers, and rock of the mantle below. A large zakelijke energie piece of it, an exotic terrane, is a part of California known in geology as the Smartville Block (47980, 484-91, 502, 504, 506). Son of a gold miner, Moores grew up in the almost alpine setting of Crown King, Arizona (526-35), and now lives in the Great Central Valley of California (535-44), whose geologic story has few (if any) parallels among valleys of the world. The Coast Ranges, with their own odd story (544-54), are only a few miles west of Moores’ home in Davis. A long set piece on world ophiolites and global tectonics-a narrative of maps in motion, of evolving and dissolving lands, including every plate and continent (554-70)-is the result of a heady conversation in the Louis Martini winery in the Napa Valley. San Francisco geology is introduced in the roadcuts of the approaching Interstate 80 and pursued on foot among the hills of the city (570-81). A set piece that traverses California the long way, north-south, is about the San Andreas system, which is actually a family of faults (581-603). Among them is the Hayward Fault, which could be a source of considerable trauma for San Francisco, Oakland, Berkeley, and all other Bay Area cities, not to mention Hayward ( 600-2). Crossing the Craton describes Nebraska by visiting Colorado, because in Colorado you see the basement of Nebraska bent up into the air. The fact that the journey takes place in the company of a geochronologist from the University of Kansas can only enhance the description. Between zakelijke energie vergelijken Chicago and Cheyenne, the most arresting geophysical feature is the Midcontinent Rift (624, 628-29, 636, 651, 654-55, 658-59), which opened about a fourth of the way back through the histo1y of the earth-i.1 billion years-and serves as an abyssal edge for a look down through deeper and deeper time.