The nineteen-seventies

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In the nineteen-seventies, she edited a book on Mesozoic mammals for the University of California Press, but her own work in geology has been at best sporadic. “In our generation,” she once remarked to me, “a woman’s place was in the home raising a family if that was what she chose to do. I brooded a little bit about this but not much. You get to be twenty-five. You kick around the options. You decide you would rather be a wife and mother than a geologist. The fact that I can talk geology with him is just gravy.” She offers her thoughts as an advocate of the geological devil to assist in the refinement of David’s ideas. “What makes you think you know that? How could you possibly infer that?” she will say to him, not always stopping short of his Celtic irascibilities. At Love Ranch, in 1910 or so, and apropos of who knows what, David’s mother asked his father, “Is it true that it is necessary to kill a Scot or agree with him?” John Love took the question seriously. After thinking it zakelijke energie vergelijken over, he answered, without elaboration, “No.” “David is not afraid of a new idea,” Jane continues. “He’s a pragmatist. He never looks back He is both ingenious and practical. On the ranch when he grew up there was no plumbing, no electricity, no automobile-and the equipment they had they repaired themselves. If he has a piece of baling wire, he can fix anything. He fixes everything from plumbing to cars. He applies the same practicality to geology. If a slide block suggests that it might go downhill, he has the physics and he knows if it will work. His talent lies particularly in his sense of cause and effect. His knowledge, experience, and curiosity extend far beyond the mere presence of a rock. He is the most creative geologist I know.” They were married in i940. Two of their four children were conceived after a summer field season zakelijke energie and born during the next one, with him off in the wild, hundreds of miles away. That, says Jane, is just one more facet of geology. On a field trip somewhere in the late nineteen-seventies, David said to me, ”I’ve been hearing about it for thirty-four years.” The summer field season begins in June and ends about four months later, during which time she seldom saw much of him in their early years, a condition she regards as follows: “My father was a lawyer in Providence. After that junior year in Wyoming, the thought of being married to a lawyer in Providence gave me claustrophobia.”

The whole world

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After her two sons were born and became old enough to coin phrases, they called her Dainty Dish and sometimes Hooty the Owl. They renamed their food, calling it, for example, dog. They called other entrees caterpillar and coyote. The kitchen stool was Sam. They named a Christmas-tree ornament Hopping John. It had a talent for remaining unbroken. They assured each other that the cotton on the branches would not melt. David decided that he was a camel, but later changed his mind and insisted that he was “Mr. and Mrs. Booth.” His mother  zakelijke energie described him as “a light-footed little elf.” She noted his developing sense of scale when he said to her, “A coyote is the whole world to a flea.”
One day, he asked her, “How long does a germ live?” She answered, “A germ may become a grandfather in twenty minutes.” He said, “That’s a long time to a germ, isn’t it?” She also made note that while David was the youngest person on the ranch he was nonetheless the most adroit at spotting arrowheads and chippings.
When David was five or six we began hunting arrowheads and chippings. While the rest of us labored along scanning gulches and anthills, David rushed by chattering and picking up arrowheads right and left. He told me once, “There’s a god of chippings that sends us anthills. He lives in the sky and tinkers with the clouds.”
The cowboys competed with Homer in the entertainment of Allan and David. There was one who-as David remembers him”could do magic tricks with a lariat rope, making it zakelijke energie vergelijken come alive all around his horse, over our heads, under our feet, zipping it back and forth around us as we jumped up and down and squealed with delight.” Somber tableaux, such as butche1ings, were played out before them as well. Years later, David would write in a letter:

The North Platte River

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“Eventually,” of course, is now. The North Platte River now flows into the rocks of the Medicine Bow Mountains, comes out again to cross the Hanna Basin, and then runs through the Seminoe Mountains and the Granite Mountains. It is joined by the Sweetwater River on the crest of the Granite Mountains. Irrespective of modern topography, the pattern of the iivers is Miocene. On the Laramie Plains, the Laramie River behaves for a while in a deceptively conventional manner. It establishes itself as the centerpiece of the basin, pretending to be the original architect of the circumvallate scene, but then takes a sharp right and, like a bull with lowered head, charges the Laramie Range. The canyon it has made is deep and wild. Water roars through it. When, in the exhumation, the river got down to the mountains, it packed the abrasive power to cut them in half. In fact, there is no obvious relationship between most of the major rivers in Wyoming and the landscapes they traverse. While rivers elsewhere, running in their dendritic patterns like the veins in a leaf, shape zakelijke energie vergelijken in harmony the landscapes they dominate, almost all the rivers of the Rockies seem to argue with nature as well as with common sense. At Devil’s Gate, on the Oregon Trail, the Sweetwater River flows into a hill of granite and out the other side. The Wind River addresses itself to the Owl Creek Mountains and flows right at them. It, too, breaks through and comes out the other side. It, too, flowed across the totally buried mountains in the Miocene, and descended upon them during the exhumation. The anomaly is so startling that early explorers, and even aborigines, did not put one and one together. To the waters on the south side of the mountains they gave the name Wind River. The waters on the north side they called the Bighorn. Eventually, they discovered Wind River Canyon. On the zakelijke energie east Rank of the Laramie Range is a piece of ground that somehow escaped exhumation. Actually contiguous with Miocene remains that extend far into Nebraska, it is the only place between Mexico and Canada where the surface that covered the mountains still reaches up to a summit.

The Hog Back

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The Hog Back was a knife-edged spur plunging off the Beaver Divide, which separates waters that flow east into the Platte from waters that flow north into the Wind, Bighorn, and Yellowstone rivers. The Hog Back was Frontier sandstone and Mowry shale, which had accumulated flat in the Cretaceous sea, and here, in subsequent time, had been bent upward sharply to make the jagged edge the travellers descended. Its shales were slick with bentonitic gumbo.
At the top of Beaver Mountain we saw the Wind River Range stretching white in the distance. The driver rough-locked the back wheels and we started down. It was a scramble for the horses to keep out of the way. There were sudden turns in the road and furrows cut by the freight wagons that almost threw the careening stage on its side. One of the horses fell, but was dragged along by the others kantoor per uur rotterdam until it finally regained its feet. We finally reached a place where the slope was less steep, the rough lock was taken off, and the driver began again to try to make tie down the hills. The little leaders ran like rats and the heavier wheelers were carried along while the coach swung from side to side in the gullies.
Twenty-six hours out of Rawlins, the stage reached Hailey. Breakfast was waiting, and in Miss Waxham’s opinion could have gone on waiting-“the same monstrous biscuits and black coffee.” A rancher named Gardiner Mills arrived-“short, dark, of caustic speech” -and handed her a big fur overcoat to top her own and keep her warm in his springy buckboard. He had come to take the new schoolmarm the remaining ten miles to his Red Bluff Ranch, and into the afternoon they travelled northwest under six-hundredfoot walls of rose, vermilion, brick, and carmine-red Triassic rock. Near a big spring under the red bluff were the  kantoor per uur almere low buildings of the ranch.
The corral and bunkhouse, grain and milk house were log structures off to one side. When we drove up to the gate, and two little narrow-chested large-pompadoured girls came out the walk to meet us, all my fears as to obstreperous pupils were at an end.

The real agency

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No one who had seen them upon the track of our present glaciers could hesitate as to the real agency by which all these erratic masses, literally covering the country, have been transported. I have had the pleasure of converting already several of the most distinguished American geologists to my way of thinking.” Henry David Thoreau took Agassiz’s book out of the Harvard library and returned it a few weeks later-perhaps unread. Apparently, Thoreau never knew that Walden Pond was a glacial kettle, had no idea that he lived among moraines and drumlins, icetransported hills. Although he and Agassiz were co-working space rotterdam acquainted and shared the same part of Massachusetts for sixteen years, there is in Thoreau’s work no discussion of glaciation. Thoreau evidently never suspected that all his N ausets and Chesuncooks, Merrimacks and Middlesex ponds had been made and shaped by ice. Agassiz was so caught up in glacial and general geology that he would try to teach it to stagecoach drivers. He believed that anyone, given a little help, could understand the nature of the earth. In Boston, in order to make his case perfectly and avoid the rockslides of his Franco-Germanic accent and syntax, he announced that he would give a series of lectures in French on the Epoque Glaciaire. People paid to hear it, and he preserved their admiration in recrystallized mots justes. When he spoke of the Jura, the Pennine Alps, and the boulders in the valleys between, no one was as co-working space almere moved as Agassiz. His great range of expression did not exclude tears. With his large forehead, full lips, aquiline nose, and shoulder-flowing hair, he all but held a baton in his hand with which to conduct the movements of the ice. One Saturday a month, he met with his friends for a late, seven-course lunch from which no one was in a hurry to go home.

In Precambrian, Cambrian

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In Precambrian, Cambrian, and much of Ordovician time, rivers ran southeastward off the American continent into the Iapetan ocean. Then the continental shelf bent low, and the Martinsburg muds poured into the depression from the east. Whether they were coming from Africa, Europe, or some accretionary, displaced, hapless Taiwan is completely unestablished, but what is not unestablished is the evidence preserved in the sediment-sand waves, ripple marks, crossbedded point bars-showing currents that flowed west and northwest. In later rock, such evidence is everywhere, showing eastern American rivers flowing toward what is now the middle of the continent all through the rest of Paleozoic time. As each successive orogeny produced another uplift in the east, fresh rivers would pour from it, building their depositional wedges, their minor and major deltas, but running always in a westerly direction. The last orogeny was pretty much spent about two hundred and fifty million years ago, in the Permian. For some tens of millions of years after that, the mountains were reduced by weather in a co-working space amsterdam tectonically quiet world. Then, in early Mesozoic time, “earth forces” began to pull the terrain apart. According to present theory, the actual split, deep enough to admit seawater, came at some point in the Jurassic. The Atlantic opened. On the American side of the break, extremely short steep rivers flowed into the new sea, but for the most part the drainages of what is now the eastern seaboard continued to flow west. By Cretaceous time, the currents had reversed, assuming the present direction of the Penobscot, the Connecticut, the Hudson, the Delaware, the Susquehanna, the Potomac, the James. Rivers come and go. They are younger by far than the rock on which they run. They wander all over their valleys and sometimes jump out. They reverse themselves and occasionally co-working space nijmegen disappeartheir behavior differentiated by textures in the solid earth below. The tightly folded Appalachians are something like the ribs of a washboard.

The turnabout

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The turnabout was at hand, however. Charles Lyell, the most outstanding British geologist of the nineteenth century, closely read the Etudes sur les Glaciers and found himself enlightened. “Lyell has adopted your theory in toto!!!” a friend wrote to Agassiz. “On my showing him a beautiful cluster of moraines, within two miles of his father’s house, he instantly accepted it, as solving a host of difficulties that have all his life embarrassed him.” Charles Darwin hurried out into the countryside to see for himself if there were “marks left by extinct glaciers.” He wrote to a friend, “I assure you, an extinct volcano could hardly leave more evident traces of its activity and vast powers ….T he valley about here and the site of the inn at which I am now writing must once have been covered by at least eight hundred or a thousand feet in co-working space rotterdam thickness of solid ice! Eleven years ago I spent a whole day in tl1e valley where yesterday everything but the ice of the glaciers was palpably clear to me, and I then saw nothing but plain water and bare rock.” The scientific dons of Cambridge continued stubborn, but-as would happen witl1 the theory of plate tectonics in the years following the revelations of the nineteen-sixties-geologists in expanding numbers accepted the glacial picture, and before long tlrnre was a low percentage that did not entlmsiastically subscribe. Delivering an address in i862 to the Geological Society of London, Sir Roderick Murchison declared without shame that he, too, now saw the picture. He sent a copy of his address to Agassiz witl1 a note that said, “I have had the sincerest pleasure in avowing that I was wrong in opposing as I did your grand and original idea of my native co-working space almere mountains. Yes! I am now convinced that glaciers did descend from the mountains to the plains as they do now in Greenland.”
Greenland is eighty-five per cent capped with ice. Anyone who doubts that we live in a glacial epoch need only note the great whiteness that Greenland contributes to a map. “The ice melted here eighteen thousand years ago,” Anita said, with a nod toward the roadside in Ohio. “It melted twelve thousand years ago in Wisconsin and Maine. If you ask a penguin in the Antarctic, the Ice Age hasn’t stopped yet.”

Appalachian sinuosity

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Some people believe that in this Appalachian sinuosity we are seeing the coastline of the Precambrian continent -North America in the good old days, when the Taconic Orogeny was off in the future and these big, scalloped bends were the bays of Iapetan seas. Signify what they may, their repetitive formality through two thousand miles does not suggest the random impacts of exotic terranes, nor, for that matter, does it suggest the ragged margins of crashing continents. The Great Valley, as the most prominent axial feature of the Appalachians, also seems inconvenient to the narrative of colliding lands, because the soft black slates and shales and the dissolving carbonates that conference room rotterdam make up the valley from end to end were all moved a great many miles northwest, and if random New Zealands and the odd Madagascar were shoving at different times in different places, one would expect the formations to be considerably offset. One would imagine that miscellaneously disturbed rock-folded, faulted, shuffled, thrusted, disarrangedwould be much too chaotically bulldozed to emerge through erosion as an integral, elongate, and geometrically formal valley. Similar thoughts come to mind with regard to the Precambrian highlands in their sinuous journey from the Great Smokies to the Green Mountains, and the Piedmont as well: the consistent, curving, parallel stripes of the conference room almere Appalachian ensemble. Anita, for the moment, was more interested in tangible limestone than in how it had been shoved and deformed. Eight miles west of Bloomsburg, she saw a limestone outcrop that looked good enough to sample. It was a quarter of a mile off the interstate, and we walked to it. She dropped some acid on it. Vigorously, the outcrop foamed. “It’s upper Silurian limestone,” she said. “I shouldn’t be able to tell you that without running the conodonts, but I know.” “What if you’re wrong?” “Then I’m wrong, aren’t I? They pay me to do the best I can. Geologists are detectives. You work with what you have.”

The sedimentary wedge

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The sedimentary wedge that has come off the Rockies is thickest there by the mountain front, and gradually thins to the east. Kansas and Nebraska are like pieces cut from a wheel of cheese-lying on their sides, thick ends to the west. Altitude in itself suggests the volume of material. Kansas and Nebraska are three thousand feet higher in the west than in the east. We were running on the summits of the Poconos-uneven but essentially level topography, the Pocono equivalent of Alpine minarets. Where we saw stratified rock in roadcuts, it seemed level enough to stop a bubble. For the most part, it was Catskill sandstone, red as borscht, from latest Devonian and earliest Mississippian time. The summits of the Poconos were not only cragless, they ran on under the scrub oaks as far as the eye could see. There were peat bogs. There was a great deal of standing water. The landscape was bestrewn with hummocky lumps of gravel. “There’s no way that streams brought all that co-working space rotterdam gravel up here,” Anita said. “Religious farmers say it’s evidence of the Great Flood.” If so, the Great Flood was frozen. These were morainal gravels, outwash gravels. Interstate 80 marks almost exactly the Wisconsinan ice sheet’s line of maximum advance in the Poconos.
We made a short digression from the interstate to see-in some Devonian siltstone-a tidal flat that was stuffed with razor clams. The surface of the rock had a Fulton Market look. It was a pai5ley of conglomerate clams. Three hundred and seventy-five million years old, they resembled exactly their modem counterparts. “Things haven’t changed much,” Anita said as she got back into the car. We drove on into Hickory Run State Park, where we walked through heavy woods toward a clear space ahead. We seemed to be approaching a body of co-working space almere water. Its edge resembled a shore, and its seventeen acres were surrounded by conifers, whose jagged silhouettes invoked a northern pond. In place of water, however, the pond consisted of boulders-thousands of big boulders, some of them thirty feet long, nearly all of them red rock weathered dusty rose, and all of them accordant with a horizontal plane, causing them to seem surreally a lake of red boulders. DAD, MOM, HARRY, and GEORGE had been there in i970 with a can of acrylic spray. JOE VIZZARD came some years later. Dozens of others had daubed the rocks on days ranging backward to i935, when the park was established. The big red-boulder expanse was difficult to cross, however, and its sorry guestbook was confined to one comer. The boulders were stunningly beautiful-in their lacustrine tranquillity, their lovely color, their spruce-rimmed absence of all but themselves. We walked out some distance, stepping from one to another multiton red potato.

West of Chicago

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West of Chicago and through most of Illinois, you would have been wading on clean sand, the quiet margin of the Canadian craton, which remained above the sea. The limy bottom apparently resumed in Iowa and went on into eastern Nebraska, and then, more or less at Kearney, you would have moved up onto a blistering-hot equatorial beach and into low terrain, subdued hills, rock that had been there a thousand million years. It was barren to a vengeance with a hint of life, possibly a hint of life-rocks stained green, stained red by algae. Wyoming. Past Laramie, you would have come to a west-facing beach and, after it, tidal mudflats all the way to Utah. The waters of the shelf would now begin to deepen. A hundred miles into Nevada was the continental slope and beyond it the blue ocean. If you had turned around and gone back after thirty million years-well into Ordovician time, say four hundred and sixty million years ago-the shelf edge would still have been near Elko, Nevada, and the gradually rising clean-lime seafloor would have reached at least to Salt Lake City. Across Wyoming, there may have been low dry land or possibly flexplek huren rotterdam continuing sea. The evidence has almost wholly worn away, but there is one clue. In southeastern Wyoming, a diamond pipe came up about a hundred million years ago, and, in the tumult that followed the explosion, marine limestone of late Ordovician age fell into the kimberlite and was preserved. In western Nebraska, you would have crossed dry and barren Precambrian terrain and by Lincoln have reached another sea. Iowa, Illinois, Indiana. The water was clear, the bottom uneven-many shallows and deeps upon the craton. In Ohio, the sea would have begun to cloud, increasingly so as you moved on east, silts slowly falling onto the lime. In Pennsylvania, as you approached the site of the future Delaware Water Gap, the bottom would have fallen away below you, and where it had earlier been close to the surface it would now be many tens of fathoms down. “The carbonate platform collapsed,” Anita said. “The continental shelf went flexplek huren almere down and formed a big depression. Sediments poured in.” Much in the way that a sheet of paper bends downward if you move its two ends toward each other in your hands, the limestones and dolomites and the basement rock beneath them had subsided, forming a trough, which rapidly filled with dark mud. The mud became shale, and when the shale was drawn into the heat and pressure of the making of mountains its minerals realigned themselves and it turned into slate. We moved on west a couple of miles and stopped at a roadcut of ebony slate. Anita said, “Twelve thousand feet of this black mud was deposited in twelve million years. That’s a big pile of rock.”