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Geochemistry

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Now, with regard to my dart in the map, he said, “If you are interested in geochemistry, the composition of the oil from those seeps has not been studied. Is it Paleozoic highsulphur oil? Mesozoic low-sulphur oil? Tertiary low-sulphur oil? One needs to know the quality of the oil and the depth of the reservoir rock.” His tone seemed to exclude both emotion and opinion. “If you’re interested in geophysics, what kinds of seismic reflections do you get from rocks below the volcanics?” he went on. “Can they be interpreted in a way that works out the prevolcanic structures? In terms of volcanic chemistry, what kinds of alteration of these Eocene volcanic rocks have occurred because of thermal activity and migration of oil into these rocks? None of this has ever been explored. In the regional context, a geologist cannot ignore the possibilities where that dart hit. A scientist, as a scientist, does not determine what should be the public policy in terms of exploration for oil and gas.” No rock could be more volcanic than the rock of Yellowstone Gorge-rose-and-burgundy, burnt-sienna, yellowcake-yellow Yellowstone¬†zakelijke energie vergelijken Gorge-where petroleum comes out of the walls with hot water and steam. In i939, when the National Park Service was digging abutments for a bridge downriver from the gorge, the National Park Service struck oil. Several workers, overcome by fumes of sulphur, died. These nagging facts notwithstanding, it was conventional wisdom in geology that where you found volcanics you would not find oil. In the nineteen-sixties, Love went out for a wider look For example, he went on horseback into the Yellowstone backcountry carrying a four-foot steel rod. Twenty miles from the trailhead, he found swamps that were something like tar pits. When he jammed the rod into a swamp, a cream-colored fluid welled up. He put it in a bottle. In a day’s time, the mixture had separated, and much of it was clear amber oil. In pursuing this project, the environmentalist within him balked, the user of resources preferred the resources somewhere else, but the scientist rode on with the rod. He knew he would bring scorn upon himself, but he was not about to stifle his science for anybody’s beliefs or opinions. He did lose friends, including zakelijke energie some Friends of the Earth. He lost friends in the Wilderness Society and the Sierra Club as well. To them, the Yellowstone oil was only the beginning of the threat he might be raising. The Designated Wilderness Areas of the United States had been selected on the assumption that they were barren of anything as vital as petroleum. “I will admit that it bothers me that I have provoked the wrath of organizations like the Sierra Club,” Love remarked that day in the cabin. “My great-uncle John Muir founded the Sierra Club, and here I am, being a traitor.”

Cycles of death

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An event of the brevity and magnitude of a great basalt flood is an obvious shock to the surface world. “We don’t know what flood basalts do to the atmosphere,” Morgan remarked one day in i985, showing me a chronology he had been making of the great flood basalts that not only filled every valley “like water” and killed every creature in areas as large as a million square kilometres but also may have spread around the world lethal effects through the sky. Morgan’s time chart of flood basalts matched almost exactly the cycles of death tlrnt are currently prominent in the dialogue of massextinction theorists, including the flood basalts of the Deccan Plateau, which are contemporaneous with the death of the dinosaursthe event that is zakelijke energie known as the Cretaceous Extinction. The perforations made by hot spots may be analogous to the perforations in sheets of postage stamps. Plume tracks might weaken the plates through which they pass, so that tens of millions of years later the plates would break apart along those lines. Madeira, for example, first drew the line where Greenland broke away from Canada. The Kerguelen Hot Spot, in the Indian Ocean, may have helped India break away from Antarctica. The Crozet Hot Spot, also in the Indian Ocean, seems to have helped Madagascar get away from Africa. In the interior of the southern supercontinent of three hundred million years ago, a hot spot punched out the line that is now the north coast of Brazil. The same line is the Gold Coast and Ivory Coast of Africa. The hot spot now stands in the Atlantic as the island St. Helena. The oldest rocks in Iceland are at the eastern and western extremes of the island, because Iceland is a hot spot whose track comes down from the northwest and at present intersects the zakelijke energie vergelijken Mid-Atlantic Ridge where Europe and America diverge. Iceland, for the time being, is spreading with the Atlantic. A hundred million years ago, the Mt. Etna Hot Spot was under the Ukraine, and seems to have cleaned off the Ukrainian Shield. A hot spot has made Ascension Island, on the South American Plate beside the Mid-Atlantic Ridge, fourteen hundred miles east of Brazil. It spent a hundred and ten million years under Africa after starting off from the Bahamas in early Jurassic time, when the transatlantic crossing was instantaneous, because there was no Atlantic.

Down toward the beaches

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Down toward the beaches flow sluggish rivers across a featureless plain. Folded and faulted schists and gneisses are bevelled under the plain, preserving in their deformation compressive crustal movements that have long since driven skyward uncounted ranges that have worn away. The Helikian beaches in their tum disappear, in burial becoming sandstone, which in the heat and pressure of more folding mountains is altered to quartzite. The mountains dissolve, and still another quiet plain vanishes below waves. The water advances into this piece of the world that will one day form as Jackson Hole. It lies close to the latitude of Holocene Sri Lanka-or Malaya, or Panama-and is moving toward the equator. The water is warm zakelijke energie vergelijken but not always quiet or clear. Blue-green algae build mounds in the shallows. There is a drop in sea level. Polygonal mud cracks become ceramic in the tropical sun. The sea returns. The water is virtually transparent, and the skeletons of billions of creatures form a pure blue-gray limestone. Like Debussy’s engulfed cathedral, the site comes up now and again into the light and air, but for the most part seas stay over it. Sands accumulatebroad, deep sands-but they preserve almost no fossil record, so not even David Love will ever say with certainty whether they are underwater or out in the air. (What he cannot say with certainty he will readily say without certainty, provided the difference is clear. He prefers not to be, as he likes to put it, “a man walking with one foot on each side of a fence.” He thinks that some of those sands were terrestrial dunes and coastlines, reddened as oxides in the air.) Jackson Hole is close to the equator, and zakelijke energie phosphates form in the shallow evaporating sea. Tidal flats appear-wide red flats, thickened by slow rivers coming from an uplift far to the east. In the muds are small tracks and tiny bones of dinosaurs. Rapidly-and possibly as a result of the breaking up of the earth’s only continent-the region travels north, moving about a thousand miles in thirty million years. Big dunes form upon the flats: dry, windblown dunes-a Sahara in salmon and red, at the precise latitudes of the modem Sahara.

The first horses on earth

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These things were very real, very practical. If you’re in bedrock, caliche, or gumbo, the going is hard. Caliche is lime precipitate at the water table-you learn some geology the hard way. There was nothing else zakelijke energie vergelijken to be interested in. Everything depended on geology. Any damn fool could see that the vegetation was directly responsive to the bedrock. Hence birds and wildlife were responsive to it. We were responsive to it. In winter, our life was governed by where the wind blew, where snow accumulated. We could see that these natural phenomena were not random-that they were controlled, that there was a system. The processes of erosion and deposition were things we grew up with. An insulated society does not see how important terrain is to someone who has to understand it in order to live with it. Much of it meant life or death for the animals, and therefore survival for us. If there was one thing we learned, it was that you don’t fight nature. You live with it. And you make the accommodations-because nature does not accommodate.” In the driest months, he saw mud cracks so firm a horse could step on them without breaking their polygonal form. When he saw the same patterns in rock, he had no difficulty discerning that the zakelijke energie rock had once been mud and that the cracks within it were the preserved summer of a former world. In the Chalk Hills (multicolored badlands), getting down from his mount, he
found the tiny jaws and small black teeth of what he eventually learned were Eocene horses-the first horses on earth, three hands tall. Among the figures that appeared on the horizon and slowly approached the ranch-and sometimes stayed indefinitely-were geologists. The first he met were from the United States Geological Survey. Others worked for oil companies. The oilmen were well dressed and had shiny boots that caught his eye. Some of these people were famous in the science-for example, Charles T. Lupton, a structural geologist who had located the wildcats of the Cat Creek Anticline and discovered the oil of Montana. He did something like it in the Bighorn Basin. David particularly remembers him on two counts: first, that he “talked about the outside world,” and, second, that he came in off the range with fragments of huge ammonites-index fossils of the late Cretaceous-and demonstrated by extrapolation that these spiral cephalopods had approached the size of wagon wheels. Lupton’s obituary in the Bulletin of the American Association of Petroleum Geologists says, “Always he had a word to say to the children of his friends.”

The subsummit surface

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Moving even farther from the interstate on the subsummit surface, we came upon a granite pyramid, sixty feet high, sixty feet wide at the base. It had been designed by the architect H. H. Richardson and weighed six thousand tons-enough to prevent its blowing over. We stood in its lee. The wind was coming in pulses that made percussions in the ears. The incongruity of this monument was in direct proportion to its stark isolation. It was Uncle Pete’s version of Interstate So’s Abraham Lincoln. It commemorated the brothers Oakes and Oliver Ames-Massachusetts shovel-makers, railroad zakelijke energie financiers-whose Credit Mobilier of America made construction contracts with itself in enjoying the fruits of subsidy of the Union Pacific Railroad. If you belonged to the United States Congress, you could buy shares of Credit Mobilier stock for fifty per cent of their value. Near the apex of the east side of the pyramid was Oliver’s face in a portrait plaque, sculptured in 1881 by Augustus SaintGaudens, whose William Tecumseh Sherman stands in Manhattan’s Grand Army Plaza and Robert Gould Shaw in Boston Common. Saint-Gaudens’ plaque of Oakes Ames was on the west side of the pyramid, facing the wind. The monument had been built beside the Union Pacific at the railroad’s highest point, but the railroad’s highest point was somewhere else now; the alignment had been changed in 1901, and the track was three or four miles away. The original roadbed had become so indistinct that a geologist was required to point out where it had been, which he did. Oakes’ nose had been shot off with a high-powered rifle. Oliver’s nose had been zakelijke energie vergelijken shot away, too, and a large part of his face. Love remarked that Greek, Roman, and Saracen vandals broke off the noses from pieces of sculpture. Probably the Vandals did, too. Back on the interstate and just west of Abraham Lincoln, the rock became younger again, as we left the Precambrian range core and encountered the same Pennsylvanian red sandstone that had leaned on the mountain on the other side. It was rich red, and the cuts were very big as the road plunged through them in christie turns, running down the mountains through Telephone Canyon. Somewhere overhead had been the first telephone wire ever strung across the Rockies. The President of the United States, with a dozen horses and companions, rode up Telephone Canyon on his way to Cheyenne in i903. His mustache was an airfoil with a fineness ratio that must have impressed the Wright brothers.

Various hiatuses

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Through the eighteen-nineties, there are various hiatuses in the resume of John Love, but as cowboy and homesteader he very evidently prospered, and he also formed durable friendships-with Chief Washakie, for example, and with the stagecoach driver Peggy Dougherty, and with Robert LeRoy Parker and Harry Longabaugh (Butch Cassidy and the Sundance Kid). There came a day when Love could not contain his developed curiosity in the presence of the aging chief. He zakelijke energie vergelijken asked him what truth there was in the story of Crowheart Butte. Had Washakie really eaten his enemy’s heart? The chief said, “Well, Johnny, when you’re young and full of life you do strange things.” Robert LeRoy Parker was an occasional visitor at Love’s homestead on Muskrat Creek, which was halfway between Hole-in-theWall and the Sweetwater River-that is, between Parker’s hideout and his woman. Love’s descendants sometimes stare bemusedly at a photograph discovered a few years ago in a cabin in Jackson Hole that had belonged to a member of the Wild Bunch. The photograph, made in the middle eighteen-nineties, shows eighteen men with Parker, who is wearing a dark business suit, a tie and a starchy white collar, a bowler hat. Two of the bunch are identified only by question marks. One of these is a jaunty man of middle height and strong zakelijke energie frame, his hat at a rakish angle-a man with a kindly face, twinkling shrewd eyes, and a mustache growing over his mouth like willows bending over a brook. It may be doubtful whether John Love would have joined such a group, but when you are young and full of life you do strange things. At Red Bluff Ranch, Mrs. Mills once twitted Mr. Love for being Scottish when other Scots were around and American in the presence of Americans. For a split second, Mr. Love thought this over before he said, “That leaves me eligible for the Presidency.” Out of Mr. Love’s buggy came a constant supply of delicacies and exotic gifts-including candy, nuts, apples-which he came by who knows where and liberally distributed to all. Miss Waxham began to look upon him as “a veritable Santa Claus”; and, predictably, at Christmastime Santa appeared.

High-country geology

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This is about high-country geology and a Rocky Mountain regional geologist. I raise that semaphore here at the start so no one will feel misled by an opening passage in which a slim young woman who is not in any sense a geologist steps down from a train in Rawlins, Wyoming, in order to go north by stagecoach into country that was still very much the Old West. She arrived in the autumn of i905, when she was twenty-three. Her hair was so blond it looked white. In Massachusetts, a few months before, she had graduated from Wellesley College and had been awarded a Phi Beta Kappa key, which now hung from a chain around her neck. Her field was classical studies. In addition to her skills in Latin and Greek, she could handle a horse expertly, but never had she made a journey into a region as remote as the one that lay before her. Meanwhile, kantoor huren per uur amersfoort Rawlins surprised her: Rawlins, where shootings had once been so frequent that there seemed to be-as citizens put it-“a man for breakfast every morning”; Rawlins, halfway across a state that was spending per annum far more to kill wolves and coyotes than to support its nineteen-year-old university. She had expected a “backward” town, a “frontier” town, a street full of badmen like Big Nose George, the road agent, the plunderer of stagecoaches, who signed his hidden-treasure maps “B. N. George.” Instead, this October evening, she was met at the station by a lackey with a hand
cart, who wheeled her luggage to the Ferris Hotel. A bellboy took over, his chest a constellation of buttons. The place was three stories high, and cozy with steam heat. The lights were electric. There were lace kantoor huren per uur enschede curtains. What does it matter, she reflected, if the pitchers lack spouts?
One spring day about three-quarters of a century later, a fourwheel-drive Bronco approached Rawlins from the east on Interstate 80. At the wheel was David Love, of the United States Geological Survey, supervisor of the Survey’s environmental branch in Laramie, and-to an extent unusual at the highest levels of the science-an autochthonous geologist.

Carboniferous sandstone

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It was rippled Carboniferous sandstone. We were still in rock of that age, but gradually and imperceptibly we had been losing altitude since we climbed the Allegheny front. The eastern rim of the plateau had been more than two thousand feet above sea level, and by now we were down to half that, as we moved farther away from the ancestral mountains and their wedge of sediment thinned. We had co-working space amersfoort come into the continent’s province of supreme tectonic calm, the Stable Interior Craton, where a thin veneer of sediment lies flat upon the stolid fundament, where the geology-even by geological standards-is exceptionally slow. “This is the most conservative part of the U.S.,” Anita said. ”I’ve often thought about it. The wildest, craziest people are in the most tectonically active places.” And yet the craton stirs. There is no part of the face of the earth that vertically and laterally does not move. The bedding planes in Midwestern rock, which appear to be absolutely level, do in fact dip. They will descend across a great many miles and then rise, arching over the far rim of a vast and shallow bowl, and then subtly dip again to form a similar bowl: the Findlay Arch, the co-working space enschede Michigan Basin, the Kankakee Arch, the Illinois Basin. Anita called the arches “basement highs.” She said Hudson Bay is a continental basin, slowly filling up. The basins of the Midwest are filled to the brim with level ground. They are products of the creaking motions of the craton, in response perhaps to plays of force from deep within the mantle-a process that, in the general phrase, is “not well understood.” They represent a degree of tectonic activity about as lively as the setting in of rigor mortis. This has not always been the regional story. There are roots of long-gone mountains deep in the rock of the stable craton, but it has not had an orogeny in a thousand million years. “What has the Midwest been doing since then? It’s been sitting around doing nothing,” Anita said. “It has just sat here hohumming.” Shallow seas may have quietly arrived and departed, and coal beds formed in the ground, but in all that time there has been¬†no occurrence that can begin to rival in scope or total change the advent from the north of walls of marching ice.

The various orogenies

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It may have been crushed and pounded in the various orogenies, and metamorphosed, too, but it was nonetheless thought to be securely glued where it first had formed as rock. The belt was supposed to have been the fixed starting block from which, somehow, thrusting had proceeded northwest. The idea had come up through the Old Geology and been incorporated into the substance of plate tectonics. Then, in i979, Vibroseis rumbled into the country and showed that from Quebec to the Blue Ridge the entire belt was deracinated. The Great Smokies and the Skyline Drive, Camp David and the Reading Prong, the Berkshires and the Green Mountains-all of it had moved, at least a few tens of miles and as much as a hundred and seventy-five miles, northwest. Using the new data, Leonard meticulously drew a palinspastic reconstruction of North American rock, showing it as it had appeared before it was co-working space apeldoorn shoved and deformed. He chose a cross section that had been shot more or less from Knoxville to Charleston and out to sea. The reconstruction showed that the rock of the Ridge and Valley-the folded-and-faulted, deformed Appalachians-had been squeezed so much that its breadth had been reduced about sixty miles. The supposedly rooted Blue Ridge had been moved inland from what is now the coast. Rock of the present Piedmont had come from three hundred miles out in the present sea. This left Africa out in the cold and plate-tectonic theory in no small need of a substitute for what had been-and in co-working space breda many classrooms would continue to be-the world’s most “classical” example of a continent-tocontinent suture. With patience geological, the believers restyled their belief, apparently according to the criterion “If at first it doesn’t fit, fit, fit again.” There was suggestive help from the West. A great deal of land out there had not been there when the carbonate rocks sloped away to ocean-crustal deeps in Ordovician time.

Coal-streaked roadcuts

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We moved on through miles of coal-streaked roadcuts, and topographically to somewhat higher ground, where the coal seams were thicker. “As you go westward and upsection, you get more coal, because the rivers, growing older, became more sluggish,” Anita
said. “The floodplains became broader. There was more ponded water. There was more area for vegetation to grow and accumulatelike the lower Mississippi Valley today.” About five miles east of Clearfield, we co-working space amersfoort stopped at a long, high throughcut full of coal. Draglines were working on both sides of the road. We chipped out some samples with rock hammers. The samples had integrity. “This is a hell of a coal,” Anita remarked. “Good commercial coal. To make it, there would have been about three thousand feet of Pennsylvanian stuff on top of it, which has been removed by erosion. Three thousand feet is the amount of overburden that will produce coal of this rank.” Stirred within by all these free B.t.u.s (twelve thousand per pound), I flailed at the cut with my rock hammer and filled a bag with good commercial coal, to take home and bum in my stove. Anita commented that coal co-working space enschede dust was blacking my face. I wiped at it with a bandanna, and asked her, “Did I get it all?” She said, “Good enough for government work.” And we headed up the road.
When the final great pulse of mountain building folded eastern Pennsylvania, the deep burial and tectonic crush may have done wonders for the coal seams there, but all the oil in the country rock was burned black and destroyed. Conodonts were blackened, too. As Anita’s many samplings would prove, conodonts become lighter in color and hue in a westward trend across the state-from black to cordovan to dusky orange to brightening levels of yellow.