Side by side

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Thumbs tucked, fingers flat, the hands side by side, she presses them hard together until they buckle upward. The hands are two continents, or other landmasses, converging, colliding-making mountains. The Himalaya was made that way. Placing the hands flat again, she slowly moves them apart. These are two plates separating, one on either side of a spreading center. The Atlantic Ocean was made that way. She begins to slide one hand under the other. This is subduction. Ocean floors are consumed that way. Thumbs tucked, fingers flat, palms again side by side, she slides one hand forward, one back, the index fingers rubbing. This is the motion of a transform fault, a strike-slip fault-the San Andreas Fault. Parts of California have slid into present place that way. Convergent margins, divergent margins, transform faults: she has outlined the boundaries of the earth’s plates. There is enough complexity in tectonics to lithify the nimblest mind, but the basic model is that simple. Take your zakelijke energie vergelijken hands with you-she smiles -and you are ready for the mountains. When I first went into the Sierra with Judy’s husband, in i978, he had an oyster-gray Volkswagen bus with a sticker on its bumper that said “Stop Continental Drift.” I guess he thought that was funny. There were not a few geologists then who really would have stopped it in its tracks if they could have figured out a mechanism for doing so, but, since no one knew then (or knows for certain now) what drives the plates, no one knew how to stop them. Plate tectonics had arrived in geology just about when Moores did, and-in his metaphor-he hit the beach in the second wave. He has called it “the realization wave”: when geologists zakelijke energie began to see the full dimensions and implications of the new theory, and the research possibilities it afforded-a scientific revolution literally on a global scale. Physiographic California, for much of its length, is divided into three parts. Where Interstate 80 crosses them, from Reno to San Francisco, they make a profile that is acutely defined: the Sierra Nevada, highest mountain range in the Lower Forty-eight; the Great Central Valley, essentially at sea level and very much flatter than Iowa or Kansas; and the Coast Ranges, a marine medley, still ascending from the adjacent sea.

Concentrated stands of lofted redoubts

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We burst into the light at the western end among concentrated stands of lofted redoubts, a garden of buttes, and huge walls of flat strata in roadcuts and rivercuts extending a full mile. William Henry Jackson photographed this scene, in i870, for the Hayden Survey. The buttes have been given names like Tollgate Rock, Teakettle Rock, Sugar Bowl Rock, Giant’s Thumb. Love said there were Indian petroglyphs on Tollgate Rock but they were far too high to see. “You’d have to be a mountain goat to get up there,” he went on, and scarce had he uttered the words when a figure white as gypsum appeared on a cone of talus at the base of the Tower sandstone, close by tl1e petroglyphs, its head in motionless silliouette. “You can tell people just to look for that goat if they want to see where the petroglyphs are,” he advised me. “They can always find the petroglyphs by looking for the goat.” About halfWay up White Mountain was a layer of sandstone that happened to be phosphatic and contained zakelijke energie uranium. Love said he knew this because he had discovered the uranium. Non-marine phosphate, largely unknown elsewhere in the world, was one of the many legacies of this strange vanished lake. A few miles back, the uraniferous phosphatic sandstone had formed a low ridge in the path of the interstate, which cut straight through it, dosing all drivers with a few milliroentgens to keep them awake. He also remarked that the sedimentary story was reflecting a lot of tectonic history. You could see the orchestration of the mountain ranges by reading backward through the layers of sediment. For example, from the age and position of the sedimentary rock derived from the Uinta Mountains and the Wind River Range you could see the Wind Rivers developing first. At all moments in the history of Lake Gosiute, it was replete with organic life, from the zakelijke energie vergelijken foul clouds of brine flies that obscured its salty flats to the twelve-foot crocodiles and forty-pound gars in the waters at their widest reach. For this was Wyoming in the Eocene, and in the lake at varying times were ictalurid catfish, bowfins, dogfish, bony tongues, donkey faces, stingrays, herring.

Where plates collide

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Where plates collide (Denali, Aconcagua, Kanchenjunga), impressive mountains form. In collision, one plate usually slides beneath the other, plunging-in the so-called subduction zone-as much as four hundred miles. The material carried down there tends to melt, and to rise as magma, reaching the surface in volcanic form, as in the Cascade Range, the Andes, the Aleutians, and Japan. Yellowstone, with all its magmatic products and bubbling sulphurs, attracts special attention in the light of this story, because Yellowstone is eight hundred miles from the nearest plate boundary. When the theory of plate tectonics developed, it asked as well as answered questions-and not a few of the questions were inconvenient to the theory. Many had to do with volcanism. For example, why was the island of Hawaii pouring out lava in the dead center of the Pacific Plate? Similarly, if volcanoes were the products of subduction zones, where was the nearest subduction zone to the Tibesti Mountains of Saharan Chad? The Tibesti massif-a couple of thousand kilometres from the leading edge of the African Plate-consists of shield volcanoes like Mauna Kea and Mauna Loa. Where was the closest subduction zone to the chain of peaks that culminates in Mt. Cameroon, a stratovolcano fifteen hundred miles from the nearest plate boundary of any kind? Moreover, some of the fine old conundrums of geology-problems that antedated the plate-tectonics revolution-remained standing in zakelijke energie vergelijken its aftermath. What could explain the Canadian Shield? The South American Shield? The South African Shield? How could so much Precambrian rock lie close to sea level and not have been buried in a thousand million years? What, in recent time, had lifted the platform of the Rockies, causing their exhumation? Why were Love and I, there on the platform, not at sea level? What had lifted the Colorado Plateau, subjecting it to incision by canyon-cutting rivers? What explained flood basalts? Plate tectonics seemed to have no relevance to them. With plate the01y, you would think you could predict the sedimentary history of continents, but you couldn’t. Why were continental basins-the Michigan Basin, the Illinois Basin, the Williston Basin-several kilometres deep? If you expect a shieldlike situation as the ultimate scene, what could zakelijke energie explain these anomalous deep basins? Oil people wanted to know most of all. They asked plate theorists, “What does plate tectonics tell us about these basins?” The answer was “Nothing.”

Narrow canyons

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He resigned to return to Wyoming with the U.S. Geological Survey, at first to pursue an assignment critical to the Second World War. The year was i942, and the United States was desperately short of vanadium, an alloy that enables steel to be effective as armor plate. Working out of Afton, in the Overthrust Belt, he looked for the metal in Permian rock. He first identified vanadium habitat (where it was in beds of black shale), and then-in winter-built a sawmill and cabins and made zakelijke energie vergelijken his own timbers for eight new mines. Afton was a Mormon redoubt. The municipal patriarch had thirtyfour children. The Loves and the haberdasher Isidor Schuster were the only Gentiles in town. Love enlisted some Mormon farmers and taught them how to mine. They worked in narrow canyons, where avalanches occurred many times a day, coming two thousand feet down the canyon walls. David was caught in one, swept away as if he were in a cold tornado, and badly injured. He lay in a hospital many weeks. Not much of him was not damaged. His complete statement of the diagnosis is “It stretched me out.” After the mines were well established, the Loves moved to Laramie, where he set up the field office that he would stay in for the rest of his U.S.G.S. career. His children grew up in Laramie. Frances now teaches French in public schools in zakelijke energie Oklahoma. The Loves’ two sons-Charles and David-are both geologists. Barbara is director of academic programs at Mukogawa Fort Wright Institute, in Spokane, a branch campus of Mukogawa Women’s University, in Nishinomiya, Japan. Gradually-as regional field offices were closed and geologists were being consolidated in large federal centers in Menlo Park (California), Reston (Virginia), and Denver-Love became vestigial in the structure of the Survey. He resisted these bureaucratic winds even when they were stiffe r than the winds that come over the Medicine Bows. “The tendency has been to have all the geologists play in one sand pile,” he once explained diplomatically. And here his friend Malcolm McKenna, curator of vertebrate paleontology at the American Museum of Natural History, took up the theme: “Dave chose to stay where the geology is, and not to go up the ladder. He was so competent the Survey tried to get him to go out of Wyoming, but he wouldn’t go. His is one of the few field offices left. The Survey gets information from people in addition to providing it. People stop in to see Dave. When he goes, the office in Laramie will close-and that will be a loss to Wyoming. While a whole bunch of people sit in little cubicles in Denver, Dave is close to the subject. He can walk out the door in the morning and do important stuff.”

A pack of ferocious wolfhounds

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There was a pack of ferocious wolfhounds in the country, kept by another flockmaster for the purpose of killing coyotes. The dogs seemed to relish killing rattlesnakes as well, shaking the life out of them until the festive serpents hung from the hounds’ jaws like fettuccine. The ranch hand in charge of them said, “They ain’t happy in the spring till they’ve been bit. They’re used to it now, and their heads don’t swell up no more.” Human beings (on foot) who happened to encounter these dogs might have preferred to encounter the  zakelijke energie rattlesnakes instead. One summer afternoon, John Love was working on a woodpile when he saw two of the wolfhounds streaking down the creek in the direction of his sons, whose ages were maybe three and four. “Laddies! Run! Run to the house!” he shouted.
“Here come the hounds!” The boys ran, reached the door just ahead of the dogs, and slammed it in their faces. Their mother was in the kitchen:
The hounds, not to be thwarted so easily, leaped together furiously at the kitchen windows, high above the ground. They shattered the glass of the small panes, and tried to struggle through, their front feet catching over the inside ledge of the window frame, and their heads, with slavering mouths, reaching through the broken glass. I had only time to snatch a heavy iron frying pan from the stove and face them, beating at those clutching feet and snarling heads. The terrified boys cowered behind me. The window sashes held against the onslaught of the zakelijke energie vergelijken hounds, and my blows must have daunted them. They dropped back to the ground and raced away.
In the boys’ vocabulary, the word “hound” joined the word “throat” in the deep shadows, and to this day when David sees a wolfhound there is a drop in the temperature of the center of his spine.

All hell broke loose

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Then all hell broke loose, and the granite rose beneath them. The granite core came up like a basement elevator that rises through a city sidewalk, pushing to either side a pair of hinged doors. That was the chronology of numerous ranges-the old hard stuff from far below breaking upward through roofrock and ultimately standing highest, while the ends of the roofrock lean on the flanks in gradations of age that are younger with distance from the core. The broken ends of that Pennsylvanian sand-the outcropping edges of the tilted strata-had weathered out as a rough, serrate ridge along the border of the range. Rocky Mountain ranges are typically flanked by such hogbacks. Boulder, Colorado, is backdropped with hogbacks (the Flatirons), which zakelijke energie vergelijken are more of the same Pennsylvanian strata leaning against the Front Range. Now, on the gangplank, Love said parenthetically, “You are seeing Paleozoic rocks for the first time since the Mississippi River. They go all the way through-under Iowa and Nebraska-but they’re buried.” In the fall of i865, Major General Grenville Dodge and his pack trains and cavalry and other troops were coming south along the St. Vrain Trail, under the front of the Laramie Range. The Powder River campaign, behind them, had been, if not a military defeat, a signal failure in its purpose: to cow the North Cheyennes and the Ogallala Sioux. General Dodge, though, was preoccupied with something else. President Lincoln, not long before he died, had instructed Dodge to choose a route for the Union Pacific Railroad. Dodge, like others before him, had sought the counsel of zakelijke energie Jim Bridger, the much celebrated trapper, explorer, fur trader, commercial entrepreneur, and all-around mountain man. Bridger, who was sixty by then, had preceded almost everybody else into the West by two or three decades and knew the country as few other whites ever would. It was he who discovered the Great Salt Lake, reporting his find as the Pacific Ocean.

Tensleep-Casper-Fountain

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There would be a risen continent reaching its coast, with rivers running over bare rock past not so much as a lichen. There would be rich-red soil on a broad lowland plain resembling Alabama (but near the equator). There would be clear, warm shelf seas. There would also be a picture of dry hot dunes, all of them facing the morning sun-the rising Miocene sun. Other-and much older-dunes would settle a great question, for it is impossible to tell now whether they were just under or just out of water. They covered all of Wyoming and a great deal more, and my have been very much like the Libyan Desert: the Tensleep-Casper-Fountain Pennsylvanian sands. There would be a picture, too, of a meandering stream, with overbank deposits, natural levees, cycads growing by the stream. Footprints the size of washtubs. A head above the trees. In the background, swamp tussocks by the shore of an oxbow lake. What was left of that picture was the Morrison formation-the Jurassic landscape of particularly dramatic dinosaurs-outcropping just up the road. There would be various views of the great Cretaceous seaway, with its plesiosaurs, its giant tmtles, its crocodiles. There would be a picture from the Paleocene of a humid subtropical swamp, and a picture from the Eocene of kantoor per uur amsterdam gravel bars in a fast river running off a mountain onto lush subtropical plains, where puppysize horses were hiding for their lives. Such pictures, made in this place, could form a tall stackscene after scene, no two of them alike. Taken together, of course -set one above another, in order-they would be the rock column for this part of Wyoming. They would correlate with what one would see in the well log of a deep-drilling rig. There would be hiatuses, to be sure. In the rock column, anywhere, more time is missing than is there; so much has been eroded away. Besides, the rock in the column is more apt to commemorate a moment-an eruption, a flood, a fallen drop of rain-than it is to report a millennium. Like a news broadcast, it is more often a montage of disasters than a cumulative kantoor per uur eindhoven record of time. I asked Love why so much of the earth’s history happened to be here on the surface in this nondescript part of the state. He said, “It just came up in the soup. Why it is out here all by itself is a matter of fierce debate.” The Rawlins Uplift had not accomplished nothing.

Travelling in Europe

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“Somebody will be shot,” said Longfellow, explaining that Emerson was too vague to be trusted with a gun. Longfellow’ s works of poetry include a birthday ballad in praise of Agassiz, which Longfellow read aloud at the Saturday Club, and in which Nature addressed the Professor:
“Come wander with me,” she said, “Into regions yet untrod; And read what is still unread In the manuscripts of God.”
John Greenleaf Whittier also wrote a poem about Agassiz, more than a hundred lines in length, ten of which are these:
Said the Master to the youth: ‘We have come in search of truth, Trying with uncertain key Door by door of mystery; We are reaching, through His laws, To the garment-hem of Cause, Him, the endless, unbegun, The unnmneable, the One Light of all our light the Source, Life of life, and Force of force.”
Longfellow, travelling in Europe in i868, called on Charles Darwin. “What a set of men you have in Camb1idge,” Darwin said to him. “Both our universities put together cannot furnish the like. Why, there is Agassiz-he counts for three.” Darwin’s generosity was remarkable in the light of Agassiz’s reaction to The Origin of Species. As Agassiz summarized it: “The world has arisen in some way or co-working space amsterdam other. How it originated is the great question, and Darwin’s theory, like all other attempts to explain the origin of life, is thus far merely conjectural. I believe he has not even made the best conjecture possible in the present state of our knowledge.” Agassiz never accepted Darwinian evolution. Many years earlier, as a young man, and as a result of his paleontological researches, he wrote the following:
More than fifteen hundred species co-working space eindhoven of fossil fishes with which I have become acquainted say to me that the species do not pass gradually from one to the other, but appear and disappear suddenly without direct relations with their predecessors; for I do not think that it can be seriously maintained that the numerous types of Cycloids and Ctenoids, which are nearly all contemporaneous with each other, descend from the Placoids and Ganoids. It would be as well to affirm that the mammals, and man with them, descend directly from fishes.

The new and reversed eastern rivers

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The new and reversed eastern rivers differentially eroded the Appalachian structures. Where they got into the shales and the carbonates, they dug deep and wide. Where they found quartzite and other metamorphic rock, they encountered tough resistance. Sometimes, working down into the country, they came to the arching quonset roofs of anticlines, and slicing their way through quartzite found limestones within. It was like slicing into the foil around a potato and finding the soft interior. The water would remove the top of the arch, dig a valley far down inside, and leave quartzite stubs to either side as ridges flanking the carbonate valley. Streams eroding headward ate up the hillsides back into the mountainsides, digging grooves toward the nearest divide. On the other side was another stream, doing the same. Working into the mountain, the two streams drew closer to each other until the divide between them broke down and they were now confluent, one stream co-working spce rotterdam changing direction, captured. In this manner, some thousands of streams-consequent streams, pirate streams, beheaded streams, defeated streams-formed and re-formed, shifting valleys, making hundreds of water gaps with the general and simple objective of finding in the newly tilted landscape the shortest possible journey to the sea. A gap abandoned by its streams is called a wind gap. In the regional context, the water gap of the Delaware River is a little less phenomenal than it once appeared to be. Until about i970, the picture in vogue of the early Cenozoic American East was of a vast peneplain, a flat world of scant relief, with oxbowed meandering rivers heading almost nowhere. The assault of water on the ancestral mountains was thought to have worn down the whole topography close to sea level. The peneplain then rose up, according to the hypothesis, and rivers dissected it, flushing out the soft rock and leaving hard co-working space utrecht rock high, in the form of remarkably level ridges-as flat as the peneplain, of which they were thought to be remnants. Where the rivers of the peneplain had flowed across the tops of buried ridges, they cut down through them as the ridges came up-making gaps. That was the history as it was taught for three-quarters of a century. It was known as the hypothesis of the Schooley Peneplain, after Schooley Mountain, in New Jersey, which looks like an aircraft carrier. The Schooley Peneplain is out of vogue. It is an emeritus idea. It has been replaced by a story out of steady-state physics having to do with the relationship of level ridgelines to certain degrees of slope. A graduate student once remarked to me that old hypotheses never really die. He said they’re like dormant volcanoes.

The well-known Cuyahoga

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We crossed a river. “That was the well-known Cuyahoga,” she said. “If you swim in it, you dissolve.” The Cuyahoga was flowing south. It rises in northeasternmost Ohio, runs south into Akron, then reverses its direction, swinging north through Cleveland and into Lake Erie. Morewarningsignsflashedby. “STAY AWAKE! STAY ALIVE!” Anita said, ‘Tm trying. I’m trying.” Now spanning the road was an Italianate steel-arch bridge, standing on Berea sandstone, a fragment of the Berea Delta, of early Mississippian age, which had extended its bird-foot shape far into Ohio Bay. We stopped, and picked quartz pebbles the size of golf balls out of a conglomerate there. “These would have been just offshore,” she said. “You can take the pebbles out of the rock with your hands because it was never hated up like the conglomerate at the Delaware Water Gap. This was never buried much. It is not well lithified. It hasn’t experienced enough heat to get tough.” A few miles west, we crossed the Cuyahoga River again, and looked down some distance from the interstate bridge into the Cuyahoga’s extensively reamed-out valley, with its modest, meandering stream. “It’s an underfit stream,” said Anita. “A little half-ass stream in a valley made wide by glacier ice. The co-working space amsterdam Cuyahoga’s valley was steepened and entrenched, like Yosemite.” “You are comparing the Cuyahoga Valley with Yosemite?” “Technically.” We left the interstate and followed the valley into Cleveland.
The Cuyahoga River had suffered a bad press. When it caught fire some years before, it attracted national attention. Its percentage of water had become low relative to its content of hydrogen in various combinations with carbon. The river burned so fiercely that two railroad bridges were nearly destroyed. There was no mention in the papers of the good things the river had done. It had made parks. It had been there before the glacier ice and had cut down five hundred feet through Mississippian formations into Senecan and Chautauquan time-stages of the late Devonian. It cut deep ravines, which the ice later broadened into canyons. The ice augered through the V-shaped valley and turned it co-working space eindhoven into a U. Which is what ice did at Yosemite-with the difference that the walls of Yosemite are speckled white granite, while the canyon walls of Cleveland are flaky black gasiferous anoxic shale. As mud, the shale was deposited in quiet water in a late Devonian sea.