Maximum tilt

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When a mountain range comes up into the air, a whole lot comes up with it. The event that had lifted the Oquirrhs-the stretching of the crust until it broke into blocks-was only among the latest of many episodes that have adjusted dramatically the appearance of central Utah. As we could plainly see from the interstate, the rock now residing in that striped mountainside had once been brutally shoved around-shoved, not pulled, and with such force that a large part of it had been tipped up more than ninety degrees, to and well beyond the zakelijke energie vergelijken vertical. Overturned. Such violence can happen on an epic scale. 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. Basin and Range faulting, on its own, has never overturned anything. The great fault blocks have a maximum tilt of thirty degrees. The event that so deformed the rock in the Oquirrhs took place roughly sixty million years agofifty-two million years before the Oquirrhs came into existenceand it was an event that made alpine fresh compressional mountains, which had their time here under the sun and were disassembled by erosion, taken down and washed away; and now those crazily upended stripes within the Oquirrhs are the evidence and fragmental remains of those ancestral mountains, brought up out of the earth and put on view as a component of new mountains. The new mountains-the mountains of the Basin and Range-are packages variously containing rock that formed at one time or another during some five hundred and fifty million years, or an eighth of the earth’s total time. It was thought until recently that older rock was in certain of the ranges, but improved techniques of dating have shown that not to be true. Seven-eighths of the earth’s time is lost here, gone without evidence-rock that disintegrated and went off to be recycled. One-eighth, for all that, is no small amount of earth history, and zakelijke energie as the great crustal blocks of the Basin and Range have tipped their mountains into the air, with individual faults offset as much as twenty thousand feet, they have brought to the surface and have randomly exposed former seafloors and basaltic dikes, entombed rivers and veins of gold, volcanic spewings and dunal sands-chaotic, concatenated shards of time.

Generally dramatic

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The change is generally dramatic as one province gives way to another; and halfWay across Pennsylvania, as you leave the quartzite ridges and carbonate valleys of the folded-and-faulted mountains, you drop for a moment into Cambrian rock near the base of a long climb, a ten-mile gradient upsection in time from the Cambrian into the Ordovician into the Silurian into the Devonian into the Mississippian (generally through the same chapters of the earth represented in the walls of the Grand Canyon) and finally out onto the Pennsylvanian itself, the upper deck, the capstone rock, of the Allegheny Plateau. Now even the Exxon map shows a new geology, roads running every which way like shatter lines in glass, following the crazed geometries of this deeply dissected country, whereas, before, the roads had no choice but to run northeast-southwest among the long ropy trends of zakelijke energie the deformed mountains, following the endless ridges. On these transcontinental trips, Karen has driven as much as a thousand miles in a day at speeds that she has come to regard as dangerous and no less emphatically immoral. She has almost never slept under a roof, nor can she imagine why anyone on such a journey would want or need to; she “scopes out” her campsites in the late-failing light with strong affection for national forests and less for the three-dollar campgrounds where you roll out your Ensolite between two trailers, where gregarious trains honk like Buicks, and Harleys on instruments climb escarpments in the night. The physiographic boundary is indistinct where you shade off the Allegheny Plateau and onto the stable craton, the continent’s enduring core, its heartland, immemorially unstrained, the steady, predictable hedreocraton-the Stable Interior Craton. There are old mountains to the east, maturing mountains to the west, adolescent mountains beyond. The craton has participated on its edges in the violent creation of the mountains. But it remains intact within, and half a nation wide-the lasting, stolid  zakelijke energie vergelijken craton, slowly, slowly downwasting. It has lost five centimetres since the birth of Christ. In much of Canada and parts of Minnesota and Wisconsin, the surface of the craton is Precambrian-earthbasement rock, the continental shield. Ohio, Indiana, Illinois, and so forth-the greater part of the Midwest-is shield rock covered with a sedimentary veneer that has never been metamorphosed, never been ground into tectonic hash–sandstones, siltstones, limestones, dolomites, flatter than the ground above them, the silent floors of departed oceans, of epicratonic seas. Iowa. Nebraska.