Apr. 24th, 2017

John McPhee's love of unusual words is on ample display here.
  • The mantle below the crust—exciting and excited by these events—would send up fillings of fluid rock, and with such pressure behind them that they could intrude between horizontal layers of, say, shale and sandstone and lift the country a thousand feet. The intrusion could spread laterally through hundreds of square miles, becoming a broad new layer—a sill—within the country rock.
  • she says, turning the sample in her hand. With a smaller hammer, she tidies it up, like a butcher trimming a roast. With a felt-tip pen, she marks it “1.” Moving along the cut, she points out xenoliths—blobs of the country rock that fell into the magma and became encased there like raisins in bread.
  • The sea is not all that responds to the moon. Twice a day the solid earth bobs up and down, as much as a foot. That kind of force and that kind of distance are more than enough to break hard rock. Wells will flow faster during lunar high tides.
  • “Roadcuts can be a godsend. There’s a series of roadcuts near Pikeville, Kentucky—very big ones—where you can see distributary channels in a riverdelta system, with natural levees, and with splay deposits going out from the levees into overbank deposits of shales and coal. It’s a face-on view of the fingers of a delta, coming at you—
  • “We as geologists are fortunate to live in a period of great road building.”
  • In no manner would one wish to mitigate the importance of the Eastern scene. Undeniably, though, the West is where the rocks are—the vastnesses of exposed rock—
  • There are mountains now behind you, mountains before you, mountains that are set on top of mountains, a complex score of underthrust, upthrust, overthrust mountains, at the conclusion of which, through another canyon, you come into the Basin and Range.
  • Triassic rock is not exclusively red, but much of it is red all over the world—red in the shales of New Jersey, red in the sandstones of Yunan, red in the banks of the Volga, red by the Sol-way Firth. Triassic redbeds, as they are called, are in the dry valleys of Antarctica, the red marls of Worcestershire,.. not merely weathered red on the surface, like the great Red-wall Limestone of the Grand Canyon, which is actually gray.
  • All over the world, so much carbon was buried in Pennsylvanian time that the oxygen pressure in the atmosphere quite possibly doubled... but what could the oxygen do? Where could it go? After carbon, the one other thing it could oxidize in great quantity was iron—abundant, pale-green ferrous iron, which exists everywhere
  • mountains rammed into thin air, with snow banners flying off the matterhorns, ridges, crests, and spurs.
  • There was fatigued rock and incompetent rock and inequigranular fabric in rock.
  • The inclination of a slope on which boulders would stay put was the angle of repose.
  • The far-out stuff was in the Far West of the country—wild, weirdsma, a leather-jacket geology in mirrored shades, with its welded tuffs and Franciscan mélange (internally deformed, complex beyond analysis), its strike-slip faults and falling buildings, its boiling springs and fresh volcanics, its extensional disassembling of the earth.
  • Meteoric water, with study, turned out to be rain. It ran downhill in consequent, subsequent, obsequent, resequent, and not a few insequent streams.
  • They say granodiorite when they are in church and granite the rest of the week.
  • Deffeyes is a big man with a tenured waistline.
  • he appears to be less attached to any one part of the story than to the entire narrative of geology in its four-dimensional recapitulations of space and time.
  • It is geologically shrewd. It was the route of animal migrations, and of human history that followed. It avoids melodrama, avoids the Grand Canyons, the Jackson Holes, the geologic operas of the country, but it would surely be a sound experience of the big picture, of the history, the construction, the components of the continent. And in all likelihood it would display in its roadcuts rock from every epoch and era.
  • The whole region, very evidently, was the bottom of a lake, for a lake itself is by definition a sign of poor drainage, an aneurysm in a river, a highly temporary feature on the land.
  • ‘Zeolite’ means ‘the stone that boils.’ If you take one small zeolite crystal, of scarcely more than a pinhead’s diameter, and heat it until the water has come out, the crystal will have an internal surface area equivalent to a bedspread. Zeolites are often used to separate one kind of molecule from another. They can, for example, sort out molecules for detergents, choosing the ones that are biodegradable. They love water. In refrigerators, they are used to adsorb water that accidently gets into the Freon.
  • When William Wyler made The Big Country, there was a climactic chase scene in which the bad guy was shot and came clattering down a canyon wall in what appeared to be a shower of clinoptilolite. Geologists were on the phone to Wyler at once. ‘Loved your movie. Where was that canyon?’
  • What we are looking at here in New Jersey is not just some little geologic feature, like a zeolite crystal. This is the opening of the Atlantic. If you want to see happening right now what happened here two hundred million years ago, you can see it all in Nevada.”
  • Deffeyes remarks. “The faunas in the high ranges here are quite distinct from one to another. Animals are isolated like Darwin’s finches in the Galapagos. These ranges are truly islands.”
  • Mountains are not somehow created whole and subsequently worn away. They wear down as they come up, and these mountains have been rising and eroding in fairly even ratio for millions of years—rising and shedding sediment steadily through time, always the same, never the same, like row upon row of fountains.
  • So in the mountains’ contest with erosion they gained in one moment about twenty thousand years. These mountains do not rise like bread. They sit still for a long time and build up tension, and then suddenly jump.
  • This Nevada topography is what you see during mountain building. There are no foothills. It is all too young. It is live country. This is the tectonic, active, spreading, mountain-building world. To a nongeologist, it’s just ranges, ranges, ranges.”
  • The crust of the Great Basin has broken into blocks. The blocks are not, except for simplicity’s sake, analogous to dominoes. They are irregular in shape. They more truly suggest stretch marks.
  • As the developing Sierra made its skyward climb—as it went on up past ten and twelve and fourteen thousand feet—it became so predominant that it cut off the incoming Pacific rain, cast a rain shadow (as the phenomenon is called) over lush, warm, Floridian and verdant Nevada. Cut it off and kept it dry.
  • happens to find there—silver, tungsten, copper, gold. An ore-deposit map and a hot-springs map will look much the same. Seismic waves move slowly through hot rock. The hotter the rock, the slower the waves. Nowhere in the continental United States do seismic waves move more slowly than they do beneath the Basin and Range.
  • The heat and the pressure are so great down there that the silt is turning into siltstone, the sand into sandstone, the mud into shale.
  • 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.
  • There is an entire nation in Europe that is upside down. It is not a superpower, but it is a whole country nonetheless—San Marino, overturned.
  • randomly exposed former seafloors and basaltic dikes, entombed rivers and veins of gold, volcanic spewings and dunal sands—chaotic, concatenated shards of time.
  • It was so thick—as much as three hundred metres thick—that crystals formed slowly in the cooling glass. “When you bury a countryside in that much rock so hot it welds, that is the ultimate environmental catastrophe,”
  • the water shrank back past Erie size and kept on shrinking and turning more and more chemical and getting smaller and shallower and shallower and smaller and near the end of its days became the Great Salt Lake.
  • In a sense, there was no beach. The basin flatness just ran to the lake and kept on going, wet. The angle formed at the shoreline appeared to be about 179.9 degrees.
  • It was sand that had formed in the lake. Just as raindrops are created around motes of dust, oolites form around bits of rock so tiny that in wave-tossed water they will stir up and move. They move, and settle, move, and settle. And while they are up in the water calcium carbonate forms around them in layer after layer, building something like a pearl.
  • And now in the autumn snow, Deffeyes and I could see shoreline terraces of Lake Bonneville a thousand feet above us on mountain slopes. That a lake so deep had been brought down to a present average depth of thirteen feet was food for melancholia.
  • Under a wind, playa lakes move like puddles of mercury in motion on a floor—two or three hundred square miles of water on the move, here today, there tomorrow
  • Salt gets into fence posts and explodes them at the base.
  • When the drivers of jet cars move at Mach .8 over the Bonneville Salt Flats, they feel that they are always about to crest a hill.
  • Enter the strange companionship of oil and salt. Oil also moves after it forms. You never find it where God put it. It moves great distances through permeable rock. ... If, however, the oil moves upward through inclined sandstone and then hits a wall of salt, it stops, and stays—trapped. Run a little drill down the side of a salt dome and when you hit “sand” it may be full of oil.



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