Bornean everglades

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The rock was now Pennsylvanian-massive river sandstones of Pennsylvanian time. Flat, deck-like, it was comparatively undisturbed. It had been shed, to be sure, from eastern mountains, but had not been much affected by their compressive drive. Crazed streams had disassembled the plateau, leaving half-eaten wedding cakes, failed pyramids, oddly polygonal hair-covered hills. Pittsburgh was built upon such geometries, its streets and roads faithful to the schizophrenic streams, its hills separating its people into socio-racial ethno-religious piles-up this one the snobs, up that the Jews, up this the co-working space eindhoven tired, up that the poor. A hundred miles northeast of Pittsburgh in the Hurrying snow there were numerous roadcuts now, and in them were upward-fining sequences of sandstones, siltstones, shales-Allegheny black shales -underlying more levels of sandstone, siltstone, and shale. “If you were a prospector for coal, you’d go bananas when you saw these black shales,” Anita said. “There ought to be coal in these roadcuts.
This is Pennsylvania in the Pennsylvanian-the home office of the rock.” Pennsylvania in the Pennsylvanian was jungle-a few degrees from the equator, like southern Indonesia and Guadalcanal. The freshwater swamp forests stood beside the nervously changing coastline of a saltwater bay, just as Sumatran swamps now stand beside the Straits of Malacca, and Bornean everglades beside the Java Sea. This was when glacial cycles elsewhere in the world were causing sea level to oscillate with geologic rapidity, and the swamps pursued the shoreline as the sea went down, and marine limestone buried the swamps as co-working space haarlem the sea returned. In just one of these cycles, the shoreline would move as much as five hundred miles-the sea transgressing and regressing through most of Pennsylvania and Ohio.

American conodonts

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They happened to be within a third of a mile of warm-water American conodonts in rock of about the same age which had moved hardly at all. The Scandinavian conodonts had apparently come to Pennsylvania with the closing of the protoAtlantic ocean and been dropped ashore off the leading edge of the arriving plate. “Even I said, ‘Oh, this piece peeled off the oncoming European-African plate and got dumped in here along with the elastics,'” Anita said, telling the story. “Everybody cited those papers. To this day they are called ‘marvellous, landmark papers.’ I could eat my heart out. The papers have been used as prime backup proofs of plate-tectonic applications in the northern Appalachians. Even now, a lot of the people who use the plate-tectonic model for interpreting the Appalachians are completely unaware that those papers were based on a paleontological misinterpretation.” Working in Nevada three years later, Anita had found Scandinavian-style conodonts of middle Ordovician age. Her husband, Leonard Harris, savored the discovery not for its conference room eindhoven embarrassment to his wife, needless to say, but for its air-brake effect on the theory of plate tectonics. “Now, how could that be?” he would ask. “How did this happen? Europe can’t hit you in Nevada.” From the Toiyabe Range she had taken the cool-water fossils, and moving east to other mountains-from basin to range-she had come to middle Ordovician carbonates that contained a mixture of conodonts of both the cool-water and the warm-water varieties, the American and the Scandinavian styles. Fartl1er east, in limestone of the same age in Utah, she had found only warm-water conodonts. She realized now the absoluteness of her error. Utah had been pretty conference room haarlem much the western extremity of the vast Bahama-like carbonate platform that covered North America under shallow Ordovician seas. In western Utah, the continental shelf had begun to angle down toward the floor of the Pacific, and in central Nevada the continent had ended in deep cool water.


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She said, ”I’d hate to tell you how many months I’ve spent here measuring every foot of rock.” Among the quartzites were occasional bands not only of sandstone but of shale. The shales were muds that had settled in a matter of days or hours and had filled in the lovely periodicity of the underlying ripples in the ancient river sand. For each picture before us in the rock, there was a corresponding picture in her mind: scenes of the early Silurian barren ground, scenes of the rivers miles wide, and, over all, a series of pictures of the big Taconic mountains to the east gradually losing their competition with erosion in the wash of Silurian rain-a general rounding down of things, with river gradients declining. There were co-working space eindhoven pictures of subsiding country, pictures of rising seas. She found shale that had been the mud of an estuary, and fossil shellfish, fossil jellyfish, which had lived in the estuary. In thin dark flakes nearby she saw “a little black lagoon behind a beach.” And in a massive layer of clear white lithified sand she saw the beach. “You don’t see sand that light except in beaches,” she said. “That is beach sand. You would have looked westward over the sea.” To travel then along the present route of Interstate 80, you would have been in need of a seaworthy shallow-draft boat. The journey could have started in mountain rapids, for the future site of the George Washington Bridge was under thousands of feet of rock. Down the huge fans of boulders and gravel that leaned against the mountains, the west-running rivers raced toward the epicontinental sea. They projected their alluvium into the water and co-working space haarlem spread it so extensively that up and down the long flanks of the Taconic sierra the alluvium coalesced, gradually building westward as an enormous collection of sediment-a deltaic complex.

Under a microscope

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She can now have a look at them under a microscope, seeing “bizarre shapes that any idiot can recognize,” and assign them variously to the Anisian, Ladinian, Cayugan, Osagean, Llandoverian, Ashgillian, or any other among tens of dozens of subdivisions of Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, and Triassic time. While recording ages, she could not ignore colors, and the question of their possible significance returned to her mind. In the Appalachians generally, formations thickened eastward. The farther east you went, the deeper the rock had once been buried-the greater the heat had once been. Heat appeared to her to have affected the color of the conodonts in the same manner that it affects the color of butter-turning it from yellow to light brown to darker brown to black-and-ruined smoking in the pan. Oh, she thought. You could use those things as thermometers. They might help in mapping flexplek huren eindhoven metamorphic rock. The process by which heat and pressure change one kind of rock into another is divided into grades of intensity. Maybe conodont colors, plotted on a map, could demonstrate the shadings of the grades. At work, she began saying to people, “Show me a conodont and I’ll tell you where in the Appalachians it came from.” With amazing accuracy she repeatedly passed the test. She imagined that color had been controlled by carbon fixing. In the presence of heat, she thought, the amount of carbon
Book 2: In Suspect Terrain in a given conodont would have remained constant while the amounts of hydrogen and oxygen declined, which is what happens in heated butter. No one seemed to agree with her. One way to test her idea might have been to scan for individual elements with an electron probe, but this was i967 and electron probes in those days could not pick up light elements like hydrogen and oxygen. She sought other avenues of proof-with other types of equipment that no one has at home. The. Geological Survey had a question for her, however. They said, “Who needs to know this anyway?” The flexplek huren haarlem Survey had been established to serve the public. “O.K., to hell with it,” Anita told herself. Half a dozen years went by. With the oil embargo of i973, the Survey felt a need to do everything possible to effect an increase in the nation’s energy resources. Its Branch of Oil & Gas Resources was expanded fifteenfold.

Modern episodes

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One of the oddities of the modern episodes of glaciation is that while threefifths of all the ice in the world covered North America and extended south of Springfield, Illinois, the valley of the Yukon River in and near Alaska was never glaciated, and as a result the gold in the Yukon drainage-the gold of the richest placer streams ever discovered in the world-was left where it lay, and was not plucked up and similarly scattered by overriding ice. Miners in Indiana learned to look in their pans for menaccanite-beanlike pebbles of iron and titanium that signalled with some consistency the propinquity of gold. The flexplek huren den haag menaccanite had come out of the exposed Precambrian core of Canada-the Canadian craton, also known as the Canadian Shield. There were garnets in the gold pans, too-and magnetite, amphibole, corundum, jasper, kyanite. Nothing in that list is native to Indiana, and all are in the Canadian Shield. There is Canadian copper in the drift of Indiana, and there are diamonds that are evidently
Canadian, too. Hundreds have been discovered-pink almondshaped hexoctahedrons, blue rhombic dodecahedrons. Weights have approached five carats, and while that is modest compared with twenty-carat diamonds found in Wisconsin, these Indiana diamonds have nonetheless been accorded the stature of individual appellations: the Young Diamond (1898), the Stanley Diamond (1900). The source of a diamond is a kimberlite pipe, a form of diatreme-a relatively small hole bored through the crust of the earth by an expanding combination of carbon dioxide and water which rises from within the earth’s mantle and moves so fast driving magma to the surface that it breaks into the atmosphere at supersonic speeds. Such events flexplek huren tilburg have occurred at random through the history of the earth, and a kimberlite pipe could explode in any number of places next year. Rising so rapidly and from so deep a source, a kimberlite pipe brings up exotic materials the like of which could never appear in the shallow slow explosion of a Mt. St. Helens or the flows of Kilauea. Among the materials are diamonds. Evidently, there are no diamond pipes, as they are also called, in or near Indiana. Like the huge red jasper boulders and the tiny flecks of gold, Indiana’s diamonds are glacial erratics.

Under the volcanoes

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Under the volcanoes, the melted crust cooled in huge volumes as new granite batholiths. Basin-range faulting has elevated the batholiths to fourteen thousand feet, and weather has sketched them out as the Sierra Nevada.
When seafloor goes into a trench, there can be a certain untidiness as segments are shaved off the top. They end up sitting on the other plate, large hunks of ocean crust that formed as much as a few thousand miles away and are now emplaced strangely among the flexplek huren eindhoven formations of the continent. The California Coast Ranges-the hills of Vallejo, the hills of San Simeon, the hills of San Francisco -are a kind of berm that was pushed up out of the water by the incoming plate, including large slices of the seafloor and a jumble of oceanic and continental materials known to geologists as the Franciscan melange. Geologists used to earn doctorates piecing together the stratigraphy of the Franciscan melange, finding bedding planes in rock masses strewn here and there, and connecting them with dotted lines. Plate tectonics reveals that there is no stratigraphy in the melange, no consecutive story of deposition-just mountains of bulldozed hash. The eastward motion of the ocean plate stopped soon after basin-range faulting began. The plate started moving in another direction. The trench, ceasing to be a trench then, was replaced by the San Andreas Fault. Mountain building, in the Old Geology, had been seen as a series of orogenies rhythmically spaced through time, in part resulting from isostatic adjustments, and in part the work of “earth forces” that were not extensively explained. As flexplek huren haarlem mountains were disassembled, their materials were deposited in huge troughs, depressions, downbendings of the crust that were known as geosynclines. Earth forces made the geosynclines. As sediment accumulated in them, its weight pressed ever farther down into the mantle until the mantle would take no more, and then there came a trampoline effect, an isostatic bounce, that caused the material to rise.

Metal discoveries

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As you know, the hot water, circulating deep, picks up whatever is there-gold, silver, molybdenum, mercury, tin, uranium-and brings it up and precipitates it out near the surface. A vein of ore is the filling of a fissure. A map of former hot springs is remarkably close to a map of metal discoveries. Old hot springs like this one brought up the silver of Nevada. It would do my heart good to find silver right here in this roadcut and put it to the local highway engineer.” He took some samples, which zakelijke energie eventually proved to be innocent of silver, and we got back into the pickup. We soon left the interstate for a secondary road heading north-up a pastel valley, tan, with a pale-green river course, fields of cattle and hay. It was a valley that had been as special to the Paiutes as the Black Hills were to the Sioux. The Paiutes gave it up slowly, killing whites in desperation to keep it, and thus bringing death on themselves. The first pioneers to settle in this “desert” were farmers-an indication of how lush and beautiful the basin must have appeared to them, ten miles wide and seventy miles long, framed in serrated ridges of north-southtrending mountains: range, basin, range. Magpies, looking like scalemodel jets, kept rising into flight from the side of the road and gaining altitude over the hood of the pickup. Deffeyes said they were underdeveloped and reminded him of Archaeopteryx, the Jurassic bird. We crossed cattle guards that were nothing more than stripes painted on the road, indicating that Nevada cattle may be underdeveloped, too, with I.Q.s in one digit, slightly lower than the national norm. For eight million years, Deffeyes was saying, as the crustal blocks inexorably pulled apart here and springs boiled up along the zakelijke energie vergelijken faults, silver had been deposited throughout the Basin and Range. The continually growing mountains sometimes fractured their own ore deposits, greatly complicating the sequence of events and confusing the picture for anyone who might come prospecting for ores. There was another phenomenon, however, that had once made prospecting dead simple. Erosion, breaking into hot-spring and vein deposits, concentrated the silver. Rainwater converted silver sulphides to silver chloride, heavy stuff that stayed right where it was andthrough thousands of millennia-increased in concentration as more rain fell.

The Old Red Sandstone

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The Old Red Sandstone was put down by rivers flowing southward to a sea where marine strata were accumulating in the region that is now called Devon. The size, speed, and direction of the riverstheir islands, pitches, and bends-are not just inferable but can almost be seen, in structures in the Old Red Sandstone: gravel bars, point bars, ripples of the riverbeds, migrating channels, “waves” that formed of sand. The sea into which those rivers spilled ran all the way to Russia, but it was in the rock zakelijke energie of Devonshire that geologists in the eighteen-thirties found cup corals-fossilized skeletons, cornucopian in shape-that were not of an age with corals they had found before. They had found related corals that were obviously less developed than these, and they had found corals that were more so. The less developed corals had been in rock that lay under the Old Red Sandstone. The more developed corals had been in rock above the Old Red Sandstone. Therefore, it was inferred (correctly) that the Old Red Sandstone of North Britain and the marine limestone of Devon were of the same age, and that henceforth any rock of that age anywhere in the world-in downtown Iowa City; on Pequop Summit, in Nevada; in Stroudsburg, Pennsylvania; in Sandusky, Ohio-would be called Devonian. It was a name given, although they did not know it then, to forty-six million years. They still had no means of measuring the time involved. They also had no way of knowing that those forty-six million years had ended a third of a billion years ago. All they had was their new and expanding insight that they were dealing with time in quantities beyond comprehension. Devonian-408 to 362 million years before the present. Geologists did not have to look long at the coal seams of Europe-the coals of the Ruhr, the coals of the Tyne-to decide that the coals were of an age, which they labelled Carboniferous. The coal and related strata lay on top of the Old Red Sandstone. So, in the zakelijke energie vergelijken succession of time, the Carboniferous period (eventually subdivided into Mississippian and Pennsylvanian in the United States) would follow the Devonian, coupling on, as the science would eventually determine, another seventy-two million years-362 to 290 million years before the present.

Great Salt Lake

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When a geologist finds oolites embedded in rock-in, say, some Cambrian \outcrop in the Lehigh Valley-the Bahamas come to mind, and the Great Salt Lake, and, by inference, a shallow, lime-rich Cambrian sea. Our sample bag was like a ten-pound sack of sugar. I rolled over on my back, set it on my stomach, and, floating a little lower, kicked in to shore. On the firm flat beach of the Great Salt Lake were many hundreds of thousands of brine flies-broad dark patche of them hopping and buzzing a steady collective electrical hum. A sacred gull
made short bursts through the brine flies, its bill clapping. Three years before gulls ate crickets and saved the Mormons, Kit Carson shot gulls to feed the starving emigrants. Gulls, though, and brine flies are natural survivors. Now, at the end of spring runoff, dead creatures were everywhere. Osmotic shock had killed shrimp outnumbering the flies. Corpses, a couple of centimetres each, lay in hydrogen-sulphide decaying stink. Interlayered with the oolites on the bottom of the lake was a kind of galantine of brine shrimp, the greasy black muck of trillions dead. Salt crystals clung like snow to our hair, and were spread on our faces like powder. In man-made ponds near the shore, the sun was making Morton’s salt. Spaced zakelijke energie along the beach were water towers, courtesy of the State of Utah. You pulled a rope and took a shower. 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. Still shrinking, it had long since become the world’s second-deadest body of water. In a couple of hundred years, it could match the Dead Sea. “Mother of God, that’s nice,” said Deffeyes suddenly, braking down the pickup on the shoulder of the road. The tip of the nose of the Stansbury Mountains had been sliced off by the interstate to reveal a sheer and massive section of handsome blue rock, thinly bedded, evenly zakelijke energie vergelijken bedded, forty metres high. Its parallel planes were tilting, dipping, gently to the east, with the exception of some confused and crumpled material that suggested a snowball splatted against glass, or a broken-down doorway in an otherwise undamaged wall.

The Avalonian Orogeny

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The swelling up of mountains was described as an orogeny. Ontogeny, phylogeny, orogeny-accent syllable two. The Antler Orogeny, the Avalonian Orogeny, the Taconic, Acadian, Alleghenian orogenies. The Laramide Orogeny. The center of the United States had had a dull geologic history-nothing much being accumulated, nothing much being eroded away. It was just sitting there conservatively. The East had once been radical-had been unstable, reformist, revolutionary, in the Paleozoic pulses of zakelijke energie vergelijken three or four orogenies. Now, for the last hundred and fifty million years, the East had been stable and conservative. 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 melange (internally deformed, complex beyond analysis), its strikeslip faults and falling buildings, its boiling springs and fresh volcanics, its extensional disassembling of the earth. There was, to be sure, another side of the page-full of geological language of the sort that would have attracted Gilbert and Sullivan. Rock that stayed put was called autochthonous, and if it had moved it was allochthonous. “Normal” meant “at right angles.” “Normal” also meant a fault with a depressed hanging wall. There was a Green River Basin in Wyoming that was not to be confused with the Green River Basin in Wyoming. One was topographical and was on Wyoming. The other was structural and was under Wyoming. The Great Basin, which is centered in Utah and Nevada, was not to be confused with the Basin and Range, which is centered in Utah and Nevada. The Great Basin was topographical, and extraordinary in the world as a vastness of land that had no drainage to the sea. The Basin and Range was a realm of related mountains that coincided with the Great Basin, spilling zakelijke energie over slightly to the north and considerably to the south.