The terminal moraine

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Did it cut from above through country now gone and lying as mud in tl1e sea? Did it work its way through the mountain as two streams, eroding headward from either side, the one finally capturing the other? Was there once a great lake spilling over the mountain and creating the gap as its outlet? The big-lake idea has attracted no support. It is looked upon less as a hypothesis than as a theoretically possible but essentially foolish guess. There was for a time an ice-defended lake between the mountain and the Wisconsinan glacier. When the ice melted, the lake ran out through the Water Gap, leaving in evidence its stream deltas and seasonally banded bottom deposits. However, Glacial Lake Sciota, as it is called, was eight miles long and two hundred feet deep and could not have cut a gap through much of anything but sugar. The ice arrived twenty-three thousand years before the present. The terminal moraine is only ten miles south of the gap. Nonetheless, the ice front was something like two thousand feet thick, for it went over the top of the mountain. It totally plugged and must have widened the Water Gap. It gouged out the riverbed and left there
afteiward two hundred feet of gravel. Indians were in the Minisink when the vegetation was tundra. Ten thousand years ago, when the vegetation changed from tundra to forest, Indians in the Minisink experienced the change. The styles in which  flexplek huren eindhoven they fractured their flint-their jasper, chert, chalcedony-can be correlated to Anatolian, Sumerian, Mosaic, and Byzantine time. Henry Hudson arrived in the New World about four hundred years before the present. He was followed by Dutch traders, Dutch colonists, Dutch miners. They discovered ore-grade copper in the Minisink, or thought they did. Part fact, part folklore, it is a tradition of the region that a man named Hendrik Van Allen assessed Kittatinny Mountain and decided it was half copper. The Dutch crown ordered him to establish a mine, and to build a road on which the ore could be removed. The road ran up the Minisink and through level country to the Hudson River at Esopus Creek (Kingston, New York). A hundred miles long, it was the first constructed highway in the New World to cover so much distance. It covers it still, and is in flexplek huren rotterdam many places scarcely changed. When Van Allen was not busy supervising the road builders, he carried on an elite flirtational minuet with the daughter of a Lenape chief. The chief was Wissinoming, his daughter Winona.

The fault

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The fault offset the water table, and the consequent release of artesian pressure sent grotesque fountains of water, sand, and gravel spurting into the air. Yet the dam at Hebgen Lake held-possibly because the lake’s entire basin subsided, in places as much as twenty-two feet. Seiche waves crossed its receding surface. A sei .che is a freshwater tsunami, an oscillation in a bathtub. The surface of Hebgen Lake was aslosh with them for twelve hours, but the first three or four were the large ones. Entering lakeside bungalows, they drowned people in flexplek huren eindhoven their beds. When a volcano lets fly or an earthquake brings down a mountainside, people look upon the event with surprise and report it to each other as news. People, in their whole history, have seen comparatively few such events; and only in the past couple of hundred years have they begun to sense the patterns the events represent. Human time, regarded in the perspective of geologic time, is much too thin to be discerned-the mark invisible at the end of a ruler. If geologic time could somehow be seen in the perspective of human time, on the other hand, sea level would be rising and falling hundreds of feet, ice would come pouring over continents and as quickly go away. Yucatans and Floridas would be under the sun one moment and underwater the next, oceans would swing open like flexplek huren rotterdam doors, mountains would grow like clouds and come down like melting sherbet, continents would crawl like amoebae, rivers would arrive and disappear like rainstreaks down an umbrella, lakes would go away like puddles after rain, and volcanoes would light the earth as if it were a garden full of fireflies. At the end of the program, man shows up-his ticket in his hand. Almost at once, he conceives of private property, dimension stone, and life insurance. When a Mt. St. Helens assaults his sensibilities with an ash cloud eleven miles high, he writes a letter to the New York Times recommending that the mountain be bombed.

A thousand million years ago

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About a thousand million years ago, a continent of unknown dimensions was rifted apart, creating an ancestral ocean more or less where the Atlantic is now. The older ocean has been called Iapetus, because Iapetus was the father of Atlas, for whom the Atlantic is named. Some geologists, who may feel that tl1eir science is dangerously clever, are snappish about Iapetus. They prefer to say protoAtlantic. The ancestral ocean existed a great ·deal longer than the Atlantic has, but gradually, across some two hundred and fifty million years in the Paleozoic era, it closed. Moving toward each other, the great landmasses on either side buckled and downwarped the continental shelves and then came together in a crash no less brutal than slow-a continent-to-continent collision marked by an alpine welt, which has reached its old age flexplek huren eindhoven as the Appalachian Mountains. In the Mesozoic era, two hundred and ten million years ago, rifting began again, pulling apart certain segments of the mountain chain, creating fault-block basins-remnants of which are the Connecticut River Valley, central New Jersey, the Gettysburg battlefields, the Culpeper Basin-and eventually parting the earth’s crust enough to start a new ocean, which is now three thousand miles wide and is Detail from “Delaware Water Gap,” by George Innes, z859. Collection of the Montclair Art Museum still growing. Meanwhile, a rhythm of glaciation has been established in what is essentially the geologic present. Ice sheets have been forming on either side of Hudson Bay and have spread in every direction to cover virtually all of Canada, New England, New York, and flexplek huren rotterdam much of New Jersey, Pennsylvania, and the Middle West. The ice has come and gone at least a dozen times, in cycles that seem to require about a hundred thousand years, and, judging by other periods of glaciation in the earlier history of the earth, the contemporary cycles have only begun. About fifty more advances can be expected. Some geologists have attempted to isolate the time in all time that runs ten thousand years from the Cro-Magnons beside the melting ice to the maternity wards of the here and now by calling it the Holocene epoch, with the implication that this is our time and place, and the Pleistocene-the “Ice Age” -is all behind us. The Holocene appears to be nothing more than a relatively deglaciated interval. It will last until a glacier two miles thick plucks up Toronto and deposits it in Tennessee. If that seems unlikely, it is only because the most southerly reach of the Pleistocene ice fields to date stopped seventy-five miles shy of Tennessee.

The best characterization

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The best characterization of the hypothesis which I have heard was the remark made at the 1922 meeting of the Geological Society of America at Ann Arbor. It was this: “If we are to believe Wegener’s hypothesis we must forget everything which has been learned in the last seventy years and start over again.”
Through the nineteen-thirties, and particularly after the Second World War, paleomagnetic data accrued, and, as it presented its story of kaleidoscopic environments changing through time in any given place, academic geologists sketched on globes and maps their curves of apparent polar wander. Here is zakelijke energie where the poles were at the end of the Silurian; this is where they went from there. Rocks of identical age, sampled in various parts of the world, indicated as much in their imprisoned compasses. Some geologists-little cells of them in South Africa, the odd don or two at Cambridge-preferred the other explanation, but they were few, and in geology departments around the world everybody would annually crowd in to hear Lucius P. Aenigmatite, Regius Professor of Historical Geology, give his world-renowned lecture ridiculing continental drift. Oil geologists, when they had found what they were looking for in deep sandstones put down by ancient rivers, naturally yearned to know in what direction those rivers had flowed. They had long since learned empirically that if you wanted to zakelijke energie vergelijken find the direction of the stream you had to use different pole positions for well cores of different ages. Whether this was the result of polar wander or continental drift did not much matter to the flying red horse. Other geologists satisfied themselves by deciding that the paleomagnetic compasses were unreliable, notwithstanding that oil companies were using them to make money. Certain English geologists produced confusion by embracing continental drift and then drawing up narratives and maps that showed continents moving all over the earth with respect to a fixed and undriftable England. By the late nineteen-fifties, paleomagnetic evidence had piled up so high that it demanded improved explication. India, for example, yielded data that put it out of harmony with the rest of the world with respect to polar wander. Either there was an inexplicable series of anomalies in the data or India itself had moved, coming up from the Southern Hemisphere and completely crossing the equator, rapidly, and at a rate of speed (as much as twenty-two centimetres a year) completely out of synchronization with the rate at which the equator’s position had differed in other terrains.

The ordinary manner

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If, in examining our land, we shall find a mass of matter which had been evidently formed originally in the ordinary manner of stratification, but which is now extremely distorted in its structure and displaced in its position,-which is also extremely consolidated in its mass and variously changed in its composition,-which therefore has the marks of its original or marine composition extremely obliterated, and many subsequent veins of melted mineral matter interjected; we should then have reason to suppose that here were masses of matter which, though not different in their origin from those that are gradually deposited at the bottom of the ocean, have been more acted upon by subterranean heat and the expanding power, that is to say, have been changed in a greater degree by the operations of the mineral region.
In that long sentence lies the discovery of metamorphic rock. But just as metamorphism will turn shale into slate, sandstone into quartzite, and granite into gneiss, Hutton had zakelijke energie turned words into pumice. Unsurprisingly, his insights did not at once spread far and wide. They received a scattered following and much abuse. The attacks were theological, in the main, but, needless to say, geological as well-particularly with regard to his elastic sense of time. Even when people began to agree that the earth must be a great deal older than six thousand years, calculations were conservative and failed to yield the reach of time that Hutton’s theory required. Lord Kelvin, as late as i899, figured that twenty-five million years was the approximate age of the earth. Kelvin was the most august figure in contemporary science, and no one stepped up to argue. Hutton published his Theory of the Earth in i 795, when almost no one doubted the historical authenticity of Noah’s Flood, and all species on earth were thought to have been zakelijke energie vergelijken created individually, each looking at the moment of its creation almost exactly as it did in modern times. Hutton disagreed with that, too. Writing a treatise on agriculture, he brought up the matter of variety in animals and noted,

The Oyster Club

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In Hutton’s description, it had once been molten, exhibiting “the liquefying power and expansive force of subterranean fire.” Hutton’s insight was phenomenal but not infallible. He saw marble as having once been lava, when in fact it is limestone cooked under pressure in place. Item by item, as the picture coalesced, Hutton did not keep it entirely to himself. He routinely spent his  zakelijke energie evenings in conversation with friends, among them Joseph Black, the chemist, whose responses may have served as a sort of fixed foot to the wide-swinging arcs of Hutton’s speculations-about the probable effect on certain materials of varying ratios of temperature and pressure, about the story of the forming of rock. Hutton was an impulsive, highly creative thinker. Black was deliberate and critical. Black had a judgmental look, a lean and somber look. Hutton had dark eyes that flashed
with humor under a far-gone hairline and an oolitic forehead full of stored information. Black is regarded as the discoverer of carbon dioxide. He is one of the great figures in the history of chemistry. Hutton and Black were among the founders of an institution called the Oyster Club, where they whiled away an evening a week with their preferred companions-Adam Smith, David Hume, John Playfair, John Clerk, Robert Adam, Adam Ferguson, and, when they zakelijke energie vergelijken were in town, visitors from near and far such as James Watt and Benjamin Franklin. Franklin called these people “a set of as truly great men …a s have ever appeared in any Age or Country.” The period has since been described as the Scottish Enlightenment, but for the moment it was only described as the Oyster Club. Hutton, who drank nothing, was a veritable cup running over with enthusiasm for the achievements of his friends. When Watt came to town to report distinct progress with his steam engine, Hutton reacted with so much pleasure that one might have thought he was building the thing himself. While the others busied themselves with their economics, their architecture, art, mathematics, and physics, their naval tactics and ranging philosophies, Hutton shared with them the developing fragments of his picture of the earth, which, in years to come, would gradually remove the human world from a specious position in time in much the way that Copernicus had removed us from a specious position in the universe. A century after Hutton, a historian would note that “the direct antagonism between science and theology which appeared in Catholicism at the time of the discoveries of Copernicus and Galileo was not seriously felt in Protestantism till geologists began to impugn the Mosaic account of the creation.”

Maximum tilt

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When a mountain range comes up into the air, a whole lot comes up with it. The event that had lifted the Oquirrhs-the stretching of the crust until it broke into blocks-was only among the latest of many episodes that have adjusted dramatically the appearance of central Utah. As we could plainly see from the interstate, the rock now residing in that striped mountainside had once been brutally shoved around-shoved, not pulled, and with such force that a large part of it had been tipped up more than ninety degrees, to and well beyond the zakelijke energie vergelijken vertical. Overturned. Such violence can happen on an epic scale. There is an entire nation in Europe that is upside down. It is not a superpower, but it is a whole country nonetheless-San Marino, overturned. Basin and Range faulting, on its own, has never overturned anything. The great fault blocks have a maximum tilt of thirty degrees. The event that so deformed the rock in the Oquirrhs took place roughly sixty million years agofifty-two million years before the Oquirrhs came into existenceand it was an event that made alpine fresh compressional mountains, which had their time here under the sun and were disassembled by erosion, taken down and washed away; and now those crazily upended stripes within the Oquirrhs are the evidence and fragmental remains of those ancestral mountains, brought up out of the earth and put on view as a component of new mountains. The new mountains-the mountains of the Basin and Range-are packages variously containing rock that formed at one time or another during some five hundred and fifty million years, or an eighth of the earth’s total time. It was thought until recently that older rock was in certain of the ranges, but improved techniques of dating have shown that not to be true. Seven-eighths of the earth’s time is lost here, gone without evidence-rock that disintegrated and went off to be recycled. One-eighth, for all that, is no small amount of earth history, and zakelijke energie as the great crustal blocks of the Basin and Range have tipped their mountains into the air, with individual faults offset as much as twenty thousand feet, they have brought to the surface and have randomly exposed former seafloors and basaltic dikes, entombed rivers and veins of gold, volcanic spewings and dunal sands-chaotic, concatenated shards of time.

Generally dramatic

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The change is generally dramatic as one province gives way to another; and halfWay across Pennsylvania, as you leave the quartzite ridges and carbonate valleys of the folded-and-faulted mountains, you drop for a moment into Cambrian rock near the base of a long climb, a ten-mile gradient upsection in time from the Cambrian into the Ordovician into the Silurian into the Devonian into the Mississippian (generally through the same chapters of the earth represented in the walls of the Grand Canyon) and finally out onto the Pennsylvanian itself, the upper deck, the capstone rock, of the Allegheny Plateau. Now even the Exxon map shows a new geology, roads running every which way like shatter lines in glass, following the crazed geometries of this deeply dissected country, whereas, before, the roads had no choice but to run northeast-southwest among the long ropy trends of zakelijke energie the deformed mountains, following the endless ridges. On these transcontinental trips, Karen has driven as much as a thousand miles in a day at speeds that she has come to regard as dangerous and no less emphatically immoral. She has almost never slept under a roof, nor can she imagine why anyone on such a journey would want or need to; she “scopes out” her campsites in the late-failing light with strong affection for national forests and less for the three-dollar campgrounds where you roll out your Ensolite between two trailers, where gregarious trains honk like Buicks, and Harleys on instruments climb escarpments in the night. The physiographic boundary is indistinct where you shade off the Allegheny Plateau and onto the stable craton, the continent’s enduring core, its heartland, immemorially unstrained, the steady, predictable hedreocraton-the Stable Interior Craton. There are old mountains to the east, maturing mountains to the west, adolescent mountains beyond. The craton has participated on its edges in the violent creation of the mountains. But it remains intact within, and half a nation wide-the lasting, stolid  zakelijke energie vergelijken craton, slowly, slowly downwasting. It has lost five centimetres since the birth of Christ. In much of Canada and parts of Minnesota and Wisconsin, the surface of the craton is Precambrian-earthbasement rock, the continental shield. Ohio, Indiana, Illinois, and so forth-the greater part of the Midwest-is shield rock covered with a sedimentary veneer that has never been metamorphosed, never been ground into tectonic hash–sandstones, siltstones, limestones, dolomites, flatter than the ground above them, the silent floors of departed oceans, of epicratonic seas. Iowa. Nebraska.