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She swung full force with her sledgehammer. The stone did not crack. “This profession is very physical,” she complained, and belted the outcrop again. Her knees sometimes turn black-and-blue when she carries samples down from mountains. She once handed a suitcase to a Greyhound bus driver who said, “What have you got in here, baby -rocks?” She was content to have them ride in the baggage compartment. A geologist I know in California would be unnerved by that. When conference room almere he travels home from far parts of the world, he buys two airline seats-one for himself and one for his rocks. We passed Limestoneville. We crossed Limestone Run and the West Branch of the Susquehanna, and now the road was running in a deep crease, a V with sides of about twelve hundred vertical feet: White Deer Ridge and Nittany Mountain-quartzites of early Silurian age, shed west from the Taconic Orogeny. There were quartzite boulders all through the steep woods but a notable absence of outcrops, of roadcuts, of exposures of any kind. In fact, with the exception of the limestones she had collected, we were not seeing much rock to write home about, and Anita was becoming impatient. “No wonder I never did geology in this part of Pennsylvania,” she said. “There are no exposures-just conference room amsterdam colluvium lying in the woods.” Multiple ridges were squeezed in close here. Characteristically, the interstate would yield to the country, to the southwestward sweep of the corrugated mountains, as it ran in a valley under a flanking ridge, biding its time for a gap. One would soon appear-not a national landmark with a history of landscape painters and lovestruck Indians, but a water gap, nonetheless-sliced clean through the ridge. Like a fullback finding a hole in the line, the road would cut right and go through. On the far side, it would break into the clear again, veering southwestward in another valley, gradually moving over toward the next long ridge. There would be another gap. Small streams had cut countless gaps. All within twenty miles of one another, for example, were Bear Gap in Buffalo Mountain, Green Gap in Nittany Mountain, Fryingpan Gap in Naked Mountain, Fourth Gap in White Deer Ridge, Third Gap, Second Gap, First Gap, Schwenks Gap, Spruce Gap, Stony Gap, Lyman Gap, Black Gap, McMurrin Gap, Frederick Gap, Bull Run Gap, and Glen Cabin Gap-among others.

Anita lost her balance and almost went below. “What a klutz,” she remarked. I thought I might be learning a geologic term. “These are periglacial boulders,” she went on. “They’re not erratics. They haven’t really moved. In the climates we have now, big boulders that are not erratics just don’t appear in the woods. Only a remarkable set of conditions would produce this scene. You had to start with the right bedrock. You had to have the right angle of dip, the right erosional shape for flushing, the right distance from the glacier. The co-working space almere terminus of the glacier was about half a mile away. The climate was arctic. Imagine the frost heaves after water in summer got into the bedrock and that kind of winter came to explode it. Gravels, sands, and clay were completely flushed away by meltwater, leaving these boulders.”
Twenty-five thousand years ago-in the late Pleistocene, or, relatively speaking, the geologic present-arctic frost had broken out the boulders and had begun the weathering that rounded them. The Acadian mountains, wearing away three hundred and fifty million years ago, had provided the material of which the boulders were made. Back on the interstate and continuing across the Pocono Plateau, we ran through more flat-lying red strata of the same approximate age, and Anita said, “Remember the Bloomsburg? This rock is fifty million years later, and it looks like the Bloomsburg, and it was formed on another low, alluviated coastal plain, when the Acadian mountains were dying down. As I’ve been telling you, geology is predictable once you learn a few facts. Geology repeats itself all through the rock column.” On the geologic time scale, anyone could assign these events to their respective places and sense the rhythms of the cycles-rock cycles, glacial cycles, orogenic co-working space amsterdam cycles: overlapping figures in the rock. Taken all together, though, they seemed to ask somewhat more than they answered, to reveal less than nature kept concealed. The evidence showed that the Acadian mountains had come down, as had the Taconics before them, and each had spread westward new worlds of debris. One could also discern that the Acadian Orogeny had folded and faulted the sedimentary rock that had formed from the grit of the earlier mountains, and metamorphosed the rock as well-changed the shales into slates, the sandstones into quartzites, the limestones and dolomites into marble.

The formation was called Martinsburg. It had been folded and cleaved in orogenic tumult following its deposition in the sea. As a result, it resembled stacks of black folios, each of a thousand leaves. Just to tap at such rock and remove a piece of it is to create something so beautiful in its curving shape and tiered laminations that it would surely be attractive to a bonsai gardener’s eye. It seems a proper setting for a six-inch tree. I put a few pieces in the car, as I am wont to do when I see some Martinsburg. Across the Delaware, in Pennsylvania, the formation presents itself in large sections that are without joints and veins, the minerals line up finely in dense flat sheets, and the foliation planes are so extensive and straight that slabs of great size can be sawed from the earth. The rock there is described as “blue-gray true unfading slate.” It is strong but “soft,” and will accept a polishing that makes it smoother than glass. From Memphis to St. Joe, from Joplin to River City, there is flexplek huren almere scarcely a hustler in the history of pool who has not racked up his runs over Martinsburg slate. For anybody alive who still hears corruption in the click of pocket billiards, it is worth a moment of reflection that not only did all those pool tables accumulate on the ocean floor as Ordovician guck but so did the blackboards in the schools of all America. The accumulation of the Martinsburg-the collapsing platform, the inpouring sediments-was the first great sign of a gathering storm. Geological revolution, crustal deformation, tectonic upheaval
would follow. Waves of mountains would rise. Martinsburg time in earth history is analogous to the moment in flexplek huren amsterdam human history when Henry Hudson, of the Dutch East India Company, sailed into the bay of the Lenape River. Completing the crossing of the Great Valley of the Appalachians, Anita and I passed more limestones, more slate. Their original bedding planes, where we could discern them, were variously atilt, vertical, and overturned, so intricate had the formations become in the thrusting and folding of the long-gone primal massifs. The road came to the river, turned north to run beside it, and presented a full view of the break in the Kittatinny ridge, still far enough away to be comprehended in context but close enough to be seen as the phenomenon it is: a mountain severed, its folds and strata and cliffs symmetrical, thirteen hundred feet of rock in close fraternal image from the skyline to the boulders of a blue-and-white river. Small wonder that painters of the Hudson River School had come to the Delaware to do their best work. George Inness painted the Delaware Water Gap many times, and he chose this perspective-downriver about four miles-more than any other.

Hutton, with his depths of time-his vision of great crustal changes occurring slowly through unguessable numbers of years-opened the way to Darwin (time is the first requirement of evolution) and also placed emphasis on repetitive processes and a sense that change is largely gradual. In contemporary dress, these concepts are still at odds in geology. Some geologists seem to look upon the rock record as a frieze of catastrophes interspersed with gaps, while flexplek huren almere others prefer to regard everything from rockslides and volcanic eruptions to rifted continents and plate collisions as dramatic passages in a quietly unfolding story. If you grow up in Brooklyn, you are free to form your prejudices where you may. Anita Epstein’s sense of the dynamics of the earth underwent considerable adjustment one night in i959, when she and her husband were on summer field assignment in southwestem Montana. They were there to do geologic mapping and studies in structure and stratigraphy in the Madison Range and the Gallatin Range, where Montana is wrapped around a comer of Yellowstone Park. They lived in a U.S.G.S. house trailer in a grove of aspens on the Blameystone Ranch, a lovely piece of terrain whose absent owner was Emmett J. Culligan, the softener of  flexplek huren amsterdam water. Since joining the Survey, they had worked in Pennsylvania, mapping quadrangles in the region of the Delaware Water Gap, and had spent the winter at headquarters in Washington, and now they were being given a chance to see some geology in a part of the United States where it is particularly visible-in Anita’s words, “where it all hangs out.” The ranch was close by Hebgen Lake, which owed itself to a dam in the valley of the Madison River. The valley ran along the line of a fault that was thought to be inactive until that night. The air was crisp. The moon was full. The day before, a fire watcher in a tower in the Gallatins had become aware of an unnerving silence. The birds were gone, he realized. Birds of every sort had made a wholesale departure from his mountain. It would be noted by others that bears had taken off as well, while bears that remained walked preoccupied in circles.

“Does this much go?” he says. “Or do the Mojave and Baja go with it?” A train of flatcars pounds through town carrying aircraft engines. My mind has drifted outside the building. I am wondering what these people in this dry basin-a mile above sea level-would think if they knew what Deffe yes was doing, if they were confronted with the news tl1at an ocean may open in their town. I will soon find out. “What?” “Are you stoned?” “The way I see it, I won’t be here, so the hell with it.” “It’s a little doubtful. It could be, but it’s a little doubtful.” “If it happens real quick, I guess a couple of people will die, but if it’s like most other things they’ll find out about it hundreds of years before and move people out of here. The whole world will probably go to hell before that happens anyway.” “You mean salt water, crests, troughs, big splash, and flexplek huren almere all that? Don’t sweat it. You’re safe here-as long as Pluto’s out there.” “We got a boat.” “That’s the best news I’ve heard in a couple of years. When I go bye-bye to the place below, why, that water will be there to cool me. I hope it’s Saturday night. I won’t have to take an extra bath.” “It may be a good thing, there’s so many politicians; but they may get an extra boat. I used to be a miner. Oh, I’ve been all over. But now they’ve got machines and all the miners have died.” “The entire history of Nevada is one of plant life, animal life, and human life adapting to very difficult conditions. People here are the most individualistic you can find. As district attorney, I see examples of it every day. They want to live free from government interference. They don’t fit into a structured way of life. This flexplek huren amsterdam area was settled by people who shun progress. Their way of life would be totally unattractive to most, but they chose it. They have chosen conditions that would be considered intolerable elsewhere. So they would adapt, easily, to the strangest of situations.” “I’ve been here thirty-three years, almost half of that as mayor. I can’t quite imagine the sea coming in-although most of us know that this was all underwater at one time. I know there’s quite a fault that runs to the east of us here. It may not be active. But it leaves a mark on your mind.”

“The vestiges of the rupture reveal themselves,” he continued, “if someone brings forward a map of the world and considers carefully the …p rojecting parts of Europe and Africa … along with the recesses of America.” In centuries that followed, various writers called attention to the suggestive shapes of landmasses, but almost no one else imagined that the landmasses had been driven apart, let alone by what mechanism. In 1838, the Scottish philosopher Thomas Dick, of zakelijke energie County Angus, published his Celestial Scenery; or, the Wonders of the Planetary System Displayed: Illustrating the Perfections of Deity and a Plurality of Worlds, in which he noted how neatly western Africa could lock itself tight around the horn of Brazil, “and Nova Scotia and Newfoundland would block up a portion of the Bay of Biscay and the English Channel, while Great Britain and Ireland would block up the entrance to Davis’s Straits.” Such an assembly would “form one compact continent.” And “a consideration of these circumstances renders it not altogether improbable that these continents were originally conjoined, and that, at some former physical revolution or catastrophe, they may have been rent asunder by some tremendous power, when the waters of the ocean rushed in between them, and left them separated as we now behold them.” I am indebted to Alan Goodacre, of the Geological Survey of Canada, for this high-assay nugget, and to James Romm, of Bard College, for the quotations from Ortelius, which they separately reported in the British journal Nature in 1991 and 1994, backdating by three centuries zakelijke energie vergelijken the continental-drift hypothesis attributed in textbooks to the meteorologist Alfred Wegener, of Graz in the Styrian Alps. Ortelius and Dick fared better than Wegener, for while their propositions achieved no significant attention, Wegener’ s won a considerable fame that rapidly decayed into notoriety.

With enough burial, the muds became limestone, the sands became sandstone, the vegetation coal. When the sea fell, erosion wore away some of that, but then the sea would rise again to bury new generations of ferns and trees under successive layers of rock. These cyclothems, as they are called, contain the coals of Pennsylvania, and similar ones the coals of Iowa and Illinois. The shallow sea that reached into western Pennsylvania and eastern Ohio was a hundred miles wide in the Missourian age of Pennsylvanian time, and after crossing the water you would have reached a beach and another coal swamp and then, in light-gray soil, a low lush tropical forest that went on through Indiana to eastern Illinois, where it ended with more coal swamps, another sea. The far shore was where the Mississippi River is now, and beyond that was an equatorial rain forest, which ended in central Iowa with another swamp, another sea. The water here was clear and zakelijke energie sparkling, with almost no land-derived sediments settling into it, just accumulating skeletons-clean deep beds of lime. Five hundred miles over the water, you would have raised the rose-colored beaches of eastern Wyoming. Mountains stood out to the south. They were the Ancestral Rockies, and time would bevel them to stumps. Skirting them, in Pennsylvanian Wyoming, you would have traversed what seem to have been Saharan sands, wave after wave of dunal sands, five hundred miles of rose and amber pastel sands, ending at the west coast of North America, in Salt Lake City. As the Pennsylvanian sea level moved up and down here, it left alternating beds of lime and sand, which, two eras later, the nascent Oquirrh Mountains would lift to view. Two hundred miles out to sea was the site of zakelijke energie vergelijken Carlin Canyon, where muds of clean lime were settling. The Stratheam, the younger formation of the two in the Carlin unconformity, is an almost pure limestone. The two formations, conjoined, were driven upward, according to present theory, in a collision of crustal plates that occurred in the early Triassic.

“Through the loyal devotion of his pupils, he was elevated even in his lifetime into the position of a kind of scientific pope, whose decisions were final on any subject regarding which he chose to pronounce them ….T racing in the arrangement of the rocks of the earth’s crust the history of an original oceanic envelope, finding in the masses of granite, gneiss, and mica-schist the earliest precipitations from that ocean, and recognising the successive alterations in the constitution of the water as witnessed by the series of geological formations, Werner launched upon the world a bold conception which might well fascinate many a listener to whom the laws of chemistry and physics, even zakelijke energie as then understood, were but little known.” Moreover, Werner’s earth was compatible witl1 Genesis and was thus not unpleasing to the Pope himself. When Werner’s pupils, as they spread through the world, encountered reasoning that ran contrary to Werner’s, pictures that failed to resemble his picture, they described all these heresies as “visionary fabrics”- including James Hutton’s Theory of the Earth; or, an Investigation of the Laws Observable in the Composition, Dissolution, and Restoration of Land Upon the Globe, which was first presented before the Royal Society of Edinburgh at its March and April meetings in i 785. Hutton was a medical doctor who gave up medicine when he was twenty-four and became a farmer who at the age of forty-two retired from the farm. Wherever he had been, he had found himself drawn to riverbeds and cutbanks, ditches and borrow pits, coastal outcrops and upland cliffs; and if he saw black shining cherts in the white chalks of Norfolk, fossil clams in the Cheviot Hills, he wondered why they were there. He had become preoccupied with the operations of the earth, and he was beginning to discern a zakelijke energie vergelijken gradual and repetitive process measured out in dynamic cycles. Instead of attempting to imagine how the earth may have appeared at its vague and unobservable beginning, Hutton thought about the earth as it was; and what he did permit his imagination to do was to work its way from the present moment backward and forward through time. By studying rock as it existed, he thought he could see what it had once been and what it might become. He moved to Edinburgh, with its geologically dramatic setting, and lived below Arthur’s Seat and the Salisbury Crags, remnants of what had once been molten rock. It was impossible to accept those battlement hills precipitating in a sea. Hutton had a small fortune, and did not have to distract himself for food.

The mantle is solid. Only in certain pockets near the surface does it turn into magma and squirt upward. The temperature of the mantle varies widely, as would the temperature of anything that is two thousand miles thick. Under the craton, it is described as chilled. By surface standards, though, it is generally white hot, everywhere around the world-white hot and solid but magisterially viscous, permitting the crust above it to “float.” Deffeyes was in his bathtub one Saturday afternoon thinking about the viscosity of the mantle. Suddenly he stood up and reached for a towel. “Piano wire!” he said to himself, and he dressed zakelijke energie vergelijken quickly and went to the library to look up a book on piano tuning and to calculate the viscosity of the wire. Just what he guessed-1022 poises. Piano wire. Look under the hood of a well-tuned Steinway and you are looking at strings that could float a small continent. They are rigid, but ever so slowly they will sag, will slacken, will deform and give way, with the exact viscosity of the earth’s mantle. “And that,” says Deffeyes, “is what keeps the piano tuner in business.” More miles, and there appears ahead of us something like a Christmas tree alone in the night. It is Winnemucca, there being no other possibility. Neon looks good in Nevada. The tawdriness is refined out of it in so much wide black space. We drive on and on toward the glow of colors. It is still far away and it has not increased in size. We pass nothing. Deffeyes says, “On these roads, it’s ten to the zakelijke energie minus five that anyone will come along.” The better part of an hour later, we come to the beginnings of the casino-flashing town. The news this year is that dollar slot machines are outdrawing nickel slot machines for the first time, ever.

“I studied roadcuts and outcrops as a kid, on long trips with my family,” Karen says. “I was probably doomed to be a geologist from the beginning.” She grew up in the Genesee Valley, and most of the long trips were down through Pennsylvania and the Virginias to see her father’s parents, in North Carolina. On such a journey, it would have been difficult not to notice all the sheets of rock that had zakelijke energie been bent, tortured, folded, faulted, crumpled-and to wonder how that happened, since the sheets of rock would have started out as flat as a pad of paper. “I am mainly interested in sedimentology, in sedimentary structures. It allows me to do a lot of field work. I’m not too interested in theories of what happens x kilometres down in the earth at certain temperatures and pressures. You seldom do field work if you’re interested in the mantle. There’s a little bit of the humanities that creeps into geology, and that’s why I am in it. You can’t prove things as rigorously as physicists or chemists do. There are no white coats in a geology lab, although geology is going that way. Under the Newark Basin are worn-down remains of the Appalachians-below us here, and under that valley, and so on over to
the Border Fault. In the West, for my thesis, I am working on a basin that also formed on top of a preexisting deformed belt. I can’t say that the basin formed just like this zakelijke energie vergelijken one, but what absorbs me are the mechanics of these successor basins, superposed on mountain belts. The Great Valley in California is probably an example of a late-stage compressional basin-formed as plates came together. We think the Newark Basin is an extensional basin-formed as plates moved apart. In the geologic record, how do we recognize the differences between the two? I am trying to get the picture of the basin as a whole, and what is the history that you can read in these cuts. I can’t synthesize all this in one morning on a field trip, but I can look at the rock here and then evaluate someone else’s interpretation.” She pauses. She looks back along the rockwall. “This interstate is like a knife wound all across the country,” she remarks. “Sure-you could do this sort of thing from here to California. Anyone who wants to, though, had better hurry. Before long, to go all the way across by yourself will be a fossil experience. A person or two. One car. Coast to coast. People do it now without thinking much about it. Yet it’s a most unusual kind of personal freedomparticular to this time span, the one we happen to be in. It’s an amazing, temporary phenomenon that will end. We have the best highway system in the world. It lets us do what people in no other country can do. And it is also an ecological disaster.”