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Geologic history

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You can see its geologic history on an ordinary map if the map shows even the rudiments of what lies below the sea. The Pacific Plate is moving northwest. It dives into the Japan Trench, the Aleutian Trench, and regurgitates the volcanic islands that lie on the far side. The plate used to move in a direction closer to true north, but forty-three million years ago it shifted course. Any hot spot now active under the Pacific Plate will produce islands or other crustal effects that appear to be moving in the opposite direction-southeast. Mauna Kea and Mauna Loa-the shield volcanoes that from seafloor to summit are the highest mountains on earth-stand close to the zakelijke energie southeasterly tip of the Hawaiian Islands. The extremely eruptive Kilauea is making the tip. The islands become lower, quieter, older-the farther they lie northwest. Islands older still-defeated by erosion-now stand below the waves. These engulfed ancestors of Hawaii form a clear track in the Pacific crust for more than five thousand miles. When their age reaches forty-three million years, their direction bends about sixty degrees to the north. Above the bend, they are known as the Emperor Seamounts. Ever older, they continue to the juncture of the Kuril and Aleutian Trenches, into which they disappear. The oldest of the Emperor Seamounts is Cretaceous in age. Mauna Loa, of course, is modern. Under the ocean forty miles southeast of Mauna Loa is Loihi, a mountain of new basalt, which has already iisen about twelve thousand feet and should make it to the surface in Holocene time.
The ages of the Emperor Seamounts and the familial Hawaiian islands create the illusion that Hawaii is propagating southeast at a rate of nine centimetres a year, while the message from plate tectonics is, of course, that the Pacific Plate is what is moving. The speeds and directions of the plates have been established by a number of corroborant observations. Offsets in faults like the San Andreas have been measured as expressions of time. Places in California that were once side by zakelijke energie vergelijken side and are now six hundred kilometres apart are also separated by eleven million years. A great deal of ocean-crustal rock has been dredged up and radioactively dated. The ages have been divided by distance from the spreading center to determine the rate at which the rock has moved. More recently, methods have been refined for making annual measurements of plate motions by satellite triangulation. Hot spots provide one more way of calculating plate velocities, for hot spots are to the drift of plates as stars to navigation.

Filed-down hammer

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“Hole” was a term used by the earliest whites to describe any valley that was closely framed by very high mountains. It was used by David Jackson, who essentially had his valley to himself, running his trap lines in the eighteen-twenties in the afternoon shadows of the Teton Range. Over time, bands of outlaws followed him, then cattlemen, and eventually homesteading farmers, whose¬†zakelijke energie fences invaded the rangeland, creating incendiary tension and setting the scene for the arrival of Shane, who came into the valley wearing no gun and “riding a lone trail out of a closed and guarded past.” A farmer offered him employment, and he accepted-earnest in his quest for a peaceful life. The farmer asked Shane almost nothing of his history but felt he could trust him and imagined a number of ways in which the man might be needed on the farm. Deep in the stranger’s saddle roll was an ivory-handled Colt revolver that came out of its holster with no apparent friction, had a filed-down hammer and no front sight, and would balance firmly on one extended finger. The farmer’s young son quite innocently discovered the gun one day, and hurried to his father. “Father, do you know what Shane has rolled up in his blankets?” “Probably a gun.” “But-how did you know? Have you seen it?” “No. That’s what he would have.” “Well, why doesn’t he ever carry it? Do you suppose maybe it’s because he doesn’t know how to use it very well?” “Son, I wouldn’t be surprised if he could take that gun and shoot the buttons off your shirt witl1 you a-wearing it and all you’d feel would be a breeze.” Shane, of course, was a zakelijke energie vergelijken fictional character, but the era he represented was a stratum of the region. In the opening words of the novel, by Jack Schaefer, “He rode into our valley in the summer of ’89.” He also glanced “over the valley to the mountains marching along the horizon.” The geography is vague, but Schaefer evidently had in mind a place beside the Bighorn Mountains.

 

Time to time

Afbeeldingsresultaat voor site:ilocate.nlFrom time to time, dust would appear on the horizon, behind a figure coming toward the ranch. The boys, in their curiosity, would climb a rooftop to watch and wait as the rider covered the intervening miles. Almost everyone who went through the region stopped at Love Ranch. It had not only the sizable bunkhouse and the most capacious horse corrals in a thousand square miles but also a spring of good water. Moreover, it had Scottish hospitality-not to mention the zakelijke energie vergelijken forbidding distance to the nearest alternative cup of coffee. Soon after Mr. Love and Miss Waxham were married, Nathaniel Thomas, the Episcopal Bishop of Wyoming, came through in his Gospel Wagon, accompanied by his colleague the Reverend Theodore Sedgwick. Sedgwick later reported (in a publication called The Spirit of Missions):
We saw a distant building. It meant water. At this lonely ranch, in the midst of a sandy desert, we found a young woman. Her husband had gone for the day over the range. Around her neck hung a gold chain with a Phi Beta Kappa key. She was a graduate of Wellesley College, and was now a Wyoming bride. She knew her Greek and Latin, and loved her horse on the care-free prairie.
The bishop said he was searching for “heathen,” and he did not linger. Fugitive criminals stopped at the ranch fairly often. They had to-in much the way that fugitive criminals in lonely country today will sooner or later have to stop at a filling station. A lone rider arrived at the ranch one day with a big cloud of dust on the horizon behind him. The dust might as well have formed in the air the letters of the word “posse.” John Love knew the rider, knew that he was wanted for murder, and knew that throughout the country the consensus was that the victim had “needed killing.” The zakelijke energie murderer asked John Love to give him five dollars, and said he would leave his pocket watch as collateral. If his offe r was refused, the man said, he would find a way to take the money. The watch was as honest as the day is long. When David does his field geology, he has it in his pocket.

General Dodge

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General Dodge went back east, and in the spring of i867 returned with his route approved. The Union Pacific at that time ended in the middle of Nebraska. He got off the train, went up the North Platte, up the Lodgepole, and, as he approached the mountains, went directly overland to Crow Creek, where he staked out the western end of the railroad’s next division. Witl1out much pleasing anybody, he named the place Cheyenne. In no time, he was defending himself against furious zakelijke energie Cheyennes. They killed soldiers and laborers, pulled up survey stakes, stole animals, and destroyed equipment. When some politicians, bureaucrats, and financiers arrived on a see-it-yourself junket west, the Cheyennes attacked them. With drawn revolver, General Dodge told his visitors, ‘We’ve got to clean these damn Indians out or give up building the Union Pacific Railroad. The government may take its choice.” The narrowest point on the gangplank is wide enough for the Union Pacific and nothing else. The interstate highway clings to one side. The tracks and lanes are so close that the gangplank resembles the neck of a guitar. A long coal freight slid by us. “The coal isn’t piled higher than the tops of the gondolas,” Love commented. “It’s an environmental move-to keep the dust from blowing downwind.” He said it was a good idea, no doubt, but he had experienced so many cinder showers earlier in his life that he could not help thinking that this latter-day assault on dust was “like bringing a fire under control at timberline.” A cinder zakelijke energie vergelijken shower was what happened when an old-time locomotive pulled into a town and blew its stack. He also said that this could not have been an important emigrant route, because there was a lack of grass and water-absolute necessities for animal-powered travel. To the Union Pacific, however, the gangplank offered speed, efficiency, and hence predominance with respect to the competition.

Probable exception

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Geologists who have grown up on shield rock-Precambrian craton-tend to be interested in copper, diamonds, iron, and gold. Most of the world’s large metal deposits are Precambrian. Diamonds, after starting upward from the mantle, seem to need the thickness of a craton to survive their journey to tl1e surface world. Geologists who grow up in California start out with strange complex structures, highly deformed rock-melanges and turbidites that seem less in zakelijke energie vergelijken need of a G. K. Gilbert than of an Alfred Adler or a Carl Jung. Shell, in its rosters, used to put an asterisk beside the names of geologists from California. The asterisk meant that while they were in, say, Texas they might be quite useful among the Gulf Coast turbidites of the Hackberry Embayment, but assign them with caution almost anywhere else. A former Shell geologist (not David Love) once said to me, “The asterisk also meant ‘Ship them back to California when they’re done.’ Shell considered them a separate race.” A geologist who grew up in Wyoming would have something of everything above-with the probable exception of the asterisk. A geologist who grew up in Wyoming could not ignore economic geology, could not ignore vertebrate paleontology, could not ignore the narrative details in any chapter of time (every period in the history of the world was represented in Wyoming). Wyoming geology would above all tend to produce a zakelijke energie generalist, with an eye that had seen a lot of rocks, and a four-dimensional gift for fitting them together and arriving at the substance of their story-a scenarist and lithographer of what geologists like to call the Big Picture.

The Findlay Arch

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The limestone had formed in the clear salt sea of middle Devonian tropical Ohio. Eventually, the sea disappeared. Two eons later, ice slid over the limestone and, retreating, left a body of fresh water that included all of what is now Lake Erie and was twice as large. “We wouldn’t be able to feed this country the way we do if much of it had not been glaciated,” Anita said. “South of the glaciers, ancient kantoor per uur breda weathering removed soluble minerals and left a rather inert soil behind. After a couple of decades of planting, you need tremendous fertilizer additions there. This glacial stuff is full of unweathered mineral material-fresh-ground rock. And under it is limestone, which is what they put on fields. When early settlers came through here and saw no trees, they moved on to places like Missouri, beyond the glacial limit, and they missed some great farmland. In Egypt, they used to get fresh minerals with every flood, but those morons built the Aswan High Dam and stopped the floods. They’re starving themselves out and making a salt pan of the delta.” We were crossing the Findlay Arch and had reached the edge of the Michigan Basin, features of the subsurface structure, invisible and unexpressed in the black level surface of silts and clays. In tropical Ohio, the arch had at one time held back a large piece of the retreating sea. As the isolated water slowly concentrated and eventually disappeared, it left Morton’s salt and U.S. gypsum. It left even more limestone. It left dolomite, anhydrite-components of what is known as the evaporite sequence. North off the interstate, we went through Gypsum, Ohio, on Sandusky Bay, and on to the lake port Marblehead, where we boarded the Kelleys Island ferry. “VISIT HISTORIC GLACIAL GROOVES,” said a sign beside the ticket booth, and soon, for a stiff toll, we were beating into an even stiffer wind, which was kantoor per uur almere tearing the caps off the waves of Lake Erie. Kelleys Island is about four miles offshore, and other cars on the ferry were stuffed with a month’s worth of groceries. A hundred and twenty people live there, year around, on four and a half square miles, and as we drove across the island we passed stone houses with red and black boulder walls-jaspers and amphibolites plucked up by the ice and brought south from the Canadian Shield.

The shadow of the rock

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We stopped on the shoulder in the shadow of the rock. “Holy Toledo, look at that son of a bitch,” Anita repeated, with her head thrown back. “Mamma mia!” The bedding was aslant in long upsweeping lines, of which a few were green. Almost due south of Lock Haven and thirty-one miles west of the Susquehanna River, it was Juniata sandstone, brought down off the Taconic uplift and spread to the west by the same system of rivers that transported the rock of the Delaware Water Gap. “This co-working space breda would be a beautiful place to measure the thickness of the section,” Anita said. “It’s completely exposed. It’s consistent. There are no faults. The thin green bands are where deposition was too rapid for oxidation to take place.” Evidence of geologists was everywhere. They had painted numbers and letters on the rock. They had removed countless paleomagnetic plugs. The bedding, seen close, was not monotonously even, as rock would be that formed in still water. Instead, it was full of the migrating channels, feathery crossbedding, natural levees, and overbank deposits of its thoroughly commemorated river. There were little maroon mud flakes. They were plucked off flats in a storm.
We went back a few miles and slowly reviewed the rock. When again we approached the huge roadcut, Anita said, “In Illinois, this would be a state park.”
The bedding planes of the Holy Toledo cut, as I would ever after refer to those enormous walls of red stone, were dipping to the east. Over the past few miles, the rock of the country had been folded ninety co-working space almere degrees. To the immediate west, therefore, we would be goiilg down in time and predictably would descend in space to a Cambra-Ordovician carbonate valley, which is what happened, as the road fell away bending left and down into Nittany Valley, where ribs of dolomite protruded here and there among rich-looking pastures turning green, gentle streamcourses, white farms. “Penn State sits on Nittany dolomite,” Anita said. “Ifs twenty miles down this valley.”

The plate-tectonics

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“The plate-tectonics people have certain set patterns that they expect to see,” Anita said. “They kind of lock themselves in. If something doesn’t fit the theory, they’ll find some sort of reason. They’ll say that something is missing, or that it was subducted, or that it has not yet been found in the subsurface. They make things fit.” “Do you believe that ocean crust is subducted into trenches, that it melts and then comes up behind the trenches as volcanoes and island arcs?” I asked her. “That is straightforward,” she said. “And I have no doubt that one edge of the Pacific Plate is grinding northwest through California. What I object to is plate tectonics taken as co-working space enschede absolute gospel. To stuff that I know about, it’s been overapplied-without attention to geologic details. It’s been misused terribly. It has misrepresented facts. It has oversimplified the world. The Atlantic spreading open I absolutely believe. How long it has been spreading open I don’t know. I don’t really believe that North America and South America were up against one another. The whole Pacific margin is thrusting from west to east, but there is no continent colliding with it. I don’t see that plate tectonics explains all of these things. I think tectonics on continents is different from tectonics in oceans, and what works in oceans is often misapplied on land. As a result, there is less understanding of regional geology. The plate-tectonic model is so generalized and is used so widely that people do not get good regional pictures anymore. People come out of universities with Ph.D.s in plate tectonics and they couldn’t identify a sulphide deposit if they fell over it. Plate tectonics is not a practical science. It’s a lot of fun and games, but it’s not how you find oil. It’s a cop-out. It’s what you do when you don’t want to think.” Before the plate-tectonics revolution, back in the penumbra of the Old Geology, mountains (as has been noted) were thought to be driven upward from a deep-seated source known as a geosynclinea profound downwarp of the crust, a long trough below the sea, which co-working space nijmegen sediments fell into. East of North America, for example, the muds that would become Martinsburg slates first became rock in a geosyncline. The great trough trended northeast, like the mountains it would produce. How the mountains came up was not absolutely defined, but the story seemed clear, even if the authorship was somewhat moot, and it was a story of rhythmically successive orogenies, chapter headings in the biography of the earth. Some geologists preferred to liken them to punctuation marks, because mountain-building phases took up so little of all time-as little as one per cent, no more than ten per cent, depending on the geologist who was calculating the time.

The carbonates

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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 co-working space breda 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 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 co-working space almere 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.

Two continents

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Two continents met to make the Urals. India, at unusual speed, hit Tibet. Eras before that, South America, Africa, and Europe had, as one, hit North America and made the Appalachians. The suture was probably the Brevard Zone, a long, northeast-trending fault zone in the southern Appalachians with very different rock types on either side and no discernible matchup of offset strata. Discontinuous extensions of the Brevard Zone seemed to reach to the Catoctin Mountains and conference room breda on to Staten Island. Southeastern Staten Island apparently was a piece of the Old World. Ships that sailed for Europe had arrived when they went under the bridge. Plate theory was constructed in ten years by people with hard data who were consciously and frankly waxing “geopoetical” as well. Once the essentials of the theory were complete-after the discovery of seafloor spreading had led to an understanding of trench subduction, and after the plates and their motions had finally been outlined and described-the theory took a metaphysical leap into the sancta of the gods, flaunting its bravado in the face of Yahweh. It could make a scientist uncomfortable. Instead of reaching back in time from rock to river to mountains that must have been thereand then on to inference and cautious conjecture in the dark of imperceivable unknowns-this theory by its conception, its nature, and its definition was applying for the job of Prime Mover. The name on the door changed. There was no alternative. The theory was panterrestrial, panoceanic. It was the past and present and future of the world, sixty miles deep. It was every scene that ever was on earth. Either it worked or it didn’t. Hoist it was to heaven with its own petard. “Established” there, it looked not so much backward from the known toward the unknown as forward from the invisible to its product the surface of the conference room almere earth. Anita was more worried than made hostile by all this. By no means did she reject plate theory out of hand. There were applications of it with which she could not agree. Moreover, it was too fast a vehicle for its keys to be given to children.