From the high ridges right down to the level of the road, there was snow all over the Ruby Mountains. “Ugh,” said Deffeyes-his comment on the snow. “Spoken like a skier,” I said. He said, ‘Tm a retired skier.” 1 He skied for the School of Mines. In other Rocky Mountain colleges and universities at the time, the best skiers in the United States were duly enrolled and trying to look scholarly and masquerading as amateurs to polish their credentials for the i952 Olympic Games. Deffeyes was outclassed even on his own team, but there came a day when a great whiteout sent the superstars sprawling on the mountain. Deffeyes’ tum for the slalom came late in the afternoon, and just as he was moving toward the gate the f hiteout turned to alpenglow, suddenly bringing into focus the well-Dmpacted snow. He shoved off, and was soon bombing. He was not hurting for weight even then. He went down the mountain like an object dropped from a zakelijke energie tower. In the end, his time placed him high among the ranking stars. Now, in the early evening, crossing Independence Valley, Deffeyes seemed scarcely to notice that the white summits of the Ruby Range-above eleven thousand feet, and the highest mountains in this part of the Great Basin-were themselves being reddened with alpenglow. He was musing aloud, for reasons unapparent to me, about the melting points of tin and lead. He was saying that as a general rule material will flow rather than fracture if it is hotter than half of its melting point measured from absolute zero. At room temperature, you can bend tin and lead. They are solid but they flow. Room temperature is more than halfway between absolute zero and the melting points of tin and lead. At room temperature, you cannot bend glass or cast iron. Room temperature is less than halfway from absolute zero to the melting points of iron and glass. “If you go down into the earth here to a depth that about equals the width of one of these fault blocks, the temperature is halfway between absolute zero and the melting point of the rock. The crust is brittle above that point and plastic below it. Where the brittleness ends is the bottom of the tilting fault block, which rests-floats, if you zakelijke energie vergelijken like-in the hot and plastic, slowly flowing lower crust and upper mantle. I think this is why the ranges are so rhythmic. The spacing between them seems to be governed by their depth-the depth of the cold brittle part of the crust. As you cross these valleys from one range to the next, you can sense how deep the blocks are.
They are all parts of the suite that opened the Atlantic seaway. The story is very similar in the Great Basinin the West, in the Basin and Range. The earth is splitting apart there, quite possibly opening a seaway. It is not something that happened a couple of hundred million years ago. It only began in the Miocene, and it is going on today. What we are ldoking 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.”
Basin. Fault. Range. Basin. Fault. Range. A mile of relief between basin and range. Stillwater Range. Pleasant Valley. Tobin Range. Jersey Valley. Sonoma Range. Pumpernickel Valley. Shoshone Range. Reese River Valley. Pequop Mountains. Steptoe Valley. Ondographic rhythms of the Basin and Range. We are maybe forty miles off the interstate, in the Pleasant Valley basin, looking up at the Tobin Range. At the zakelijke energie vergelijken nine-thousand-foot level, there is a stratum of cloud against the shoulders of the mountains, hanging like a ring of Saturn. The summit of Mt. Tobin stands clear, above the cloud. When we crossed the range, we came through a ranch on the ridgeline where sheep were fenced around a running brook and bales of hay were bright green. Junipers in the mountains were thickly hung with berries, and the air was unadulterated gin. This country from afar is synopsized and dismissed as “desert” -the home of the coyote and the pocket mouse, the side-blotched lizard and the vagrant shrew, the MX rocket and the pallid bat. There are minks and river otters in the Basin and Range. There are deer and antelope, porcupines and zakelijke energie cougars, pelicans, cormorants, and common loons. There are Bonaparte’s gulls and marbled godwits, American coots and Virginia rails. Pheasants. Grouse. Sandhill cranes. Ferruginous hawks and flammulated owls. Snow geese. This Nevada terrain is not corrugated, like the folded Appalachians, like a tubal air mattress, like a rippled potato chip. This is not-in that compressive manner-a ridge-and-valley situation.
The oldest rock yet found on earth (630, 632, 648) has an age close to four billion years, some six hundred million years younger than the earth itself. After reaching back to the earliest beginnings ( 63031), the story turns around and comes forward through the Archean Eon, while island arcs accrete and small cratons form (631-33). At the end of the Archean, in the very general neighborhood of 2.5 billion years before the present, great and unrepeatable changes occur in the behavior of the earth, including the precipitation of banded iron and the beginning of modern plate tectonics (634). In the early Proterozoic Eon, seven small cratons collide, conjoin as the Canadian Shield (633, 636-38). Younger island arcs eventually drift in and dock against the shield, forming large parts of Nebraska and Colorado (638-45). These zakelijke energie novel views into Precambrian eons are the result of advances in radiometric dating ( 645-50) and, among other things, the measurement and interpretation of magnetic and gravity anomalies (651-54), all of it anchored and restrained by well cores (654-56). More arcs accrete. A coastal plate boundary like the Andean margin of South America develops along what is now a northeasterly trend through New Mexico and Kansas (650-51). About halfway through the Proterozoic, a baffling series of great plutons (each analogous to the Sierra Nevada batholith of relatively modern times) perforates North America from one side to the other and is mysteriously unaccompanied by the building of mountains, as plutons generally are, almost by definition (652-53). A time line at i.1 billion years comes in from the eastern and western margins of the continent and converges in the active and growing Midcontinent Rift (657-58). When the spreading stops under Iowa, the granites of Pikes Peak almost unaccountably appear in Colorado, the last tectonic event in Precambrian North America (660). An editor from whose counsel I have benefitted since the early zakelijke energie vergelijken phases of this project is Sara Lippincott, of Pasadena, California, who left The New Yorker in 1993 in order to become a free-lance editor of books. When Sara lived in New York, her idea of a perfect vacation was to get in an airplane and visit Caltech.