I have a feeling that the hot-spot ideas have been somewhat enlarged beyond the facts. The term itself probably means different things to different people. To me, a hot spot is an area of abnormally high temperature gradients, so high that it can be interpreted as having an igneous mush down below. In the Snake River Plain, the volcanics do get older east to westin a broad sense, yes. But when you get down to details you get down to discrepancies. We don’t know all the ages we should, on the various sets of volcanics. We need to learn them, and plot them up in geographic and time perspective. We will-but to my satisfaction we zakelijke energie have not, yet. I would like to see a lot more regional information. In northwest Wyoming, volcanism began in the early Eocene, fifty-two million years ago. You got the Absaroka volcanic centers. Volcanic debris from them was spread by water and wind across the Wind River Basin, the Green River Basin. Then what happened? Everything went blah. The Yellowstone-Absaroka hot spot abruptly terminated at the end of Eocene time. Where the hell did that hot spot go? Twenty-five to thirty million years later, it was reactivated in the same place. What was that plume doing for all those millions of years? How do you reactivate a plume? We need answers to this sort of thing, and we don’t have them. If the plume theory is correct, you’ve got to answer those questions.”
The hail over the interstate turned to snow, and we passed a Consolidated Freightways tandem trailer lying off the shoulder with twenty-six wheels in the air-apparently overturned (a day or two before) by the wind. Abruptly, the weather changed, and we climbed the Rock Springs Uplift under blue-and-white marble skies. As we moved on to Green River and Evanston-across lake deposits zakelijke energie vergelijken and badlands, and up the western overthrust-the sun was with us to the end of Wyoming. On the state line was a flock of seagulls, in the slow lane, unperturbed, emblematically announcing Utahthese birds that saved the Mormons. Mormon traffic, heading home, did not seem intent on returning the favor.
He knows geology from having found it out himself. He has set an example of the way geology is done-one hell of an example. To compete with Dave, you’d have to do a lot of walking.” Love once picked up a mail-order catalogue and saw an item described as “Thousand Mile Socks.” He sent for them skeptically but later discovered that there was truth in the catalogue’ s claim. They were indeed thousand-mile socks. He had rapidly worn them out, but that was beside the point. Years ago, almost anybody zakelijke energie vergelijken going into geology could look forward to walking some tens of thousands of miles and seriously studying a comparable number of outcrops. Geology, by definition, was something you did in the field. You sifted fine dirt for fossils the eye could barely see. You chiselled into lithified mud to remove the legs of dinosaurs. You established time-stratigraphic relationships as you moved from rock to rock. You developed a sense of structure from, among other things, your own mapping of strikes and dips. In the vernacular of geology, your nose was on the outcrop. Through experience with structure, you reached for the implied tectonics. Gradually, as you gathered a piece here, a piece there, the pieces framed a story. Feeling a segment of the earth, you were touching a body so great in its dimensions that you were something less than humble if you did not look upon your conclusions as tentative. Like many geologists, Love became fond of the Hindu fable of the blind men and the elephant, because the poem in a few short verses allegorized for him the history and the practice of his science. “We are blind men feeling the zakelijke energie elephant,” he would say, almost ritually, as a way of reminding anyone that the crust is so extensive and complicatedand contains so little evidence of most events in earth history-that every relevant outcrop must be experienced before a regional outline can so much as be suggested, let alone a global picture.
To shorten the trip to Lander, and make his own visits more frequent, John Love bought a used Buick.
Under severe nervous and vocal strain, he taught himself to drive, alone, on a wide expanse of level ground. Automatically he called “Whoa, there!” when he wanted to stop.
He knew a stockman who, in a similar effort, had failed, and had destroyed his car with an axe. John was resolved not to let that happen to him. He triumphed, of course, and the family was soon cruising to the Sweetwater Divide, with a picnic lunch and a jug of lemonade. Their horizons, already wide, before long rapidly expanded as John decided to take the first vacation of zakelijke energie vergelijken his life in order that the boys might see the Pacific Ocean before they went to college. The Loves headed west in the Buick. They had a breadbox, a camp stove, a nest of aluminum pots. The back seat was stacked high with blankets. Suitcases rode on the running boards, and on top of the luggage was a tepee.
The boys went to the University of Wyoming, where Allan majored in civil engineering. David majored in geology, and was elected to Phi Beta Kappa. Words caived into the university sandstone said:
David stayed in Laramie to earn a master’s degree, and later, on a scholarship, went east to seek a Ph.D. at Yale. Arriving with some bewilderment in that awesome human topography, he noticed a line from Rafael Sabatini carved in stone in a courtyard of the Hall of Graduate Studies: “He was born with a gift for laughter and a sense that the world is mad.” Those words steadied him at Yale, and helped prepare him for a lifetime in government and science. As a graduate student, he had to advance his reading zakelijke energie knowledge of German, which he did over campfires on summer field work in the mountains of Wyoming. One book mentioned an inscription above a doorway at the German Naval Officers School, in Kiel-an unlikely place for a Rocky Mountain geologist to discover what became for him a lifelong professional axiom. As he renders it in English: “Say not ‘This is the truth’ but ‘So it seems to me to be as I now see the things I think I see.’ “
One after another, I chose a cobble from the roadcut, handed it to Love, and asked him what it was. A Paleozoic quartzitic sandstone, for example-probably Mississippian. Grains rounded. No biotite. In fact, no mica of any kind. A Cretaceous sandstone. That would be from nearby, not from the mountains. A Paleozoic or Precambrian chert. Some Hanna formation sandstone, Paleocene in age-the matrix of the conglomerate. Some Precambrian quartzite from the Snowy Range, two billion years old. Some bull quartz from a vein in the Precambrian. And one he didn’t know. While the orogeny was making mountains, it was also making basins, for which it is less noted, even where the basins are a good deal deeper than Mt. Everest is high. As zakelijke energie we crossed the Medicine Bow River and approached the North Platte and Rawlins, we moved out upon the surface of the Hanna Basin. It was choppy but essentially level nondescript ground, like all the rest of the rangeland on the apron of the mountains. It was not water, and we were not in a boat, but in some ways it seemed so as we crossed a basin forty-two thousand feet deep. It is the deepest structural basin in North America. It is Cretaceous, Paleocene, and Eocene rock, bent in D’s, with seams of coal as much as fifty feet thick in the arms of the D’s. D nion Pacific. We crossed the North Platte, climbed some long grades, examined a few roadcuts, and pulled off on the shoulder at Rawlins to absorb, in the multiple exposures of the Rawlins Uplift, its comprehensive spread of time-Rawlins, where his mother had boarded the stage north, three-quarters of a century before. In the United States Geological Survey’s seven-and-a-half-minute series of topographic maps is a quadrangle named Love Ranch. The landscape it depicts lies just under the forty-third parallel and west of the hundred-and-seventh meridian-coordinates that zakelijke energie vergelijken place it twelve miles from the geographic center of Wyoming. The names of its natural features are names that more or less materialized around the kitchen table when David Love was young: Corral Draw, Castle Gardens, Buffalo Wallows, Jumping-Off Draw. To the fact that he grew up there his vernacular, his outlook, his pragmatic skills, and his professional absorptions about equally attest. The term “store-bought” once brightened his eyes.
In earth history, that was not long ago. He said the best general date for it was ten million years-when the central Rocky Mountains, which had long since taken form as we know them, were bur-‘ ied up to their chins. Only the highest peaks remained uncovered, like nunataks protruding through continental ice, or scattered islands in a sea. The summits of the Wind River Range were hills above that Miocene plain. The highest of the Bighorns stuck out, too-as did the crests of other ranges. Forty million years before that, in Eocene time, most parts of the Rocky Mountains seem to have looked much as zakelijke energie vergelijken they do today, and so did the broad basins among them. The region as a whole was closer to sea level, but its relief was essentially the same. It was a bizarre story, full of odd detail. Limestone, for example, is ordinarily a marine rock, derived from corals and shells. What so1t of limestone would form on a surface that came sloping down like a tent roof from the ridgelines of buried mountains? The surface had been laced with streams, Love said, and in the rumpled topography east of the buried ranges the streams filled countless lakes. Old carbonates dissolved and were carried by the streams to the lakes. Lime also leached out of the granite in the mountain core. Freshwater limestones formed in the lakes, self-certified by the fossils of freshwater snails. There were other fossils as well-discovered in dense compilations in confined areas that have been described as concentration camps and fossil graveyards. They suggest a modem plain in south-central Brazil where heavy seasonal rains so elevate the waters of innumerable lakes that animals crowd up on small islands and perish. Limestone, being soluble in water, forms zakelijke energie fertile valleys in eastern North America but in the dry West remains largely undissolved. Its inherent ruggedness holds it high, while weaker rock around it falls away. Limestone is the protective caprock of Pine Bluffs. Junipers were flourishing in it, as were ponderosa pines and Spanish bayonets.
Less than a mile up the road, we stopped again-at a low, flaky roadcut of Mowry shale. Progressing thus across Wyoming with David Love struck me as being analogous to walking up and down outside a theatre in the company of David Garrick. The classic plays-Teton, Beartooth, Wind River-were not out here on the street, but meanwhile these roadcuts were like posters, advertising the dramatic events, suggesting their narratives, fabrics, and structures. This Mowry shale had been organic mud of the Cretaceous seafloor, wherein the oil of the Frontier could have formed. It was a shale so black it all but smelled of low tide. In it, like mica, were millions of fish scales. It was interlayered with bentonite, which is a rock so soft it is actually plastic-pliable and porous, color of cream, sometimes the color of chocolate. Bentonite is volcanic kantoor huren per uur leeuwarden tuff-decomposed, devitrified. So much volcanic debris has settled on Wyoming that bentonite is widespread and, in many places, more than ten feet thick. To some extent, it covers every basin. Also known as mineral soap, it has a magical ability to adsorb water up to fifteen times its own volume, and when this happens it offers to a tire about as much resistance as soft butter. Wet, swollen bentonite soil is known as gumbo. We were crossing badlands of the Bighorn Basin one time when a light shower fell, and the surface of the road changed in moments from dust to colloidal suspension. The wheels began to skid as if they were climbing ice. Four-wheel drive was no help. Many a geologist has walked out forty miles from a vehicle shipwrecked in gumbo. Bentonite is mined in Wyoming and sold to the rest of the world. Blessed is the land that can sell its mud. Bentonite is used in adhesives, automobile polish, detergent, and paint. It is in the drilling “mud” of oil rigs, sent down the pipe and through apertures in the bit to carry rock chips to the surface. It sticks to the walls of the drill hole and keeps out unwanted water. It is used to kantoor huren per uur eindhoven line irrigation ditches and reservoirs, and in facial makeup. Indians drove buffalo into swamps full of bentonite. It is an ingredient of insecticides, insect repellents, and toothpaste. It is used to clarify beer. If Love had ever tried bentonite to repair his air mattress, he did not mention it. He did remark that when there was rain in the Wind River Basin on the ranch where he grew up-an event that happened about as often as a birthday-wagons were stopped in their tracks.
“There I ascertained the most important fact that I now know concerning the advance of glaciers,” he wrote later. From a message in a bottle in a cabin on the ice, he had learned that the monk who built the place in i827 had returned nine years later to find it more than two thousand feet down the mountain. Agassiz established his own shelter on tl1e Aar Glacier. He and his colleagues drove stakes into the ice-a row of them straight across the glacier-and before long discovered that glacier ice, like a river, flows more rapidly in the center and also tends to speed up toward the outsides of bends. Diverting a meltwater stream that was pouring into a deep hole in the ice, he set up a sturdy tripod at the surface and had himself lowered co-working space leeuwarden into the glacier. He was twenty fathoms down in a banded sapphire world when his feet touched water and he shouted instructions that his descent be stopped. His colleagues on the glacier misinterpreted his cry and lowered him into the water. The next shout was different and was clearly understood. The dripping Agassiz was raised toward the surface among stalactites of Damoclean ice, so big that had they broken they would have killed him. Concluding the experiment, he said, “Unless induced by some powerful scientific motive, I should not advise anyone to follow my example.” The better to see the alpinevalley ice in its regional perspective, Agassiz and his team climbed mountains-they climbed the Jungfrau, the Schreckhorn, the Finsteraarhorn-and made co-working space eindhoven their observations from the summits, completely unmindful atop a number of the mountains that no one had been there before. Agassiz went to England, Scotland, Ireland, and Wales, looking for the tracks of glaciers. He found them in England, Scotland, Ireland, and Wales. As in Switzerland, he saw roches nwutonnees-humps of exposed bedrock that were characteristically smooth on the side from which the ice had arrived, and plucked and shattered on the other.
We have rock that is nearly four billion years old. So we have a problem relating. 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 co-working space groningen 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 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 co-working space den haag natural to say, ‘God, these are so different. They could be 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.”
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 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 co-working space leeuwarden 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 ice was Antarctic in breadth. The traceable co-working space eindhoven episodes of recent continental glaciation have each placed about as much ice over North America as is upon Antarctica now. In Wisconsinan time, which lasted about seventy-five thousand years and ended ten thousand years ago, three-fifths of all the ice in the world was on North America, another fifth covered much of Europe, and the rest was scattered.
A schedule of arrivals of incoming exotic terranes will account-as a simple continent-to-continent collision cannot do-for the long spreads of time between one and another of the Appalachian mountain-building pulses. As someone once compacted it for me, “you sweep the New Zealands and Madagascars out of the ocean and then you close it with the Alleghenian Orogeny.” Disagreeing interpreters see terranes of highly varied dimension. Nominated as the terrestrial remains of one exotic block is the whole of New England from Williamst own eastward, arriving in the Ordovician to lift the Taconic mountains. Exotic terranes and their effects represent only one of the responses of plate-tectonic theorists to the embarrassment caused by the failure of Exhibit A among intercontinental collisions to exhibit a finite suture. Another response conference room leeuwarden has been the notion that when two continents collide there is every possibility that one will split the other, like an axe blade entering cedar; if so, you would find the invaded country rock both above and below the invader. The concept is known as flake tectonics. Its message to Vibroseis is to stop
shaking and go home. With a little erosion and flake tectonics, you can have the native rock reaching far under the rock from across the sea. Even so, the bunching of exotic terranes seems to solve more problems than flake tectonics does. Exotic terranes not only explain the intervals of time involved in the Taconic, Acadian, Alleghenian orogenies, they suggest as well why Taconic deformation occurred in the nmthem but not the southern Appalachians. Shortening collisional boundaries, they restore some dignity to the Brevard suture. Anita turned on the windshield wipers and wiped an April shower. Beside the interstate, the Pocono Devonian roadcuts were of much the same age and character as ones we had seen before. We conference room eindhoven passed them by. “Better not to do geology in the rain,” Anita said. “It’s unfair to the rocks.” With regard to the possibility of exotic terranes having added themselves to eastern North America, she said, “If you stretch out the overthrusts in the Appalachians, they show that-before the mountain building began-the continent was much larger than it is now, not smaller.”