Static science

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“They didn’t all pooch out at once. They moved in fits and starts over a span of time. The Owl Creeks rose in the early Eocene, as did the Uintas. The Medicine Bows, which are farther east, came up before the Uintas. They are all separate mountains with the same general type of origin. They are cohesive in the way that a family is cohesive. They are part of tl1e same event.” The event is known in geology as the Laramide Orogeny. Alternatively it is called the Laramide Revolution. Mountains always come down, of course, as they are coming up. In the contest between erosion and orogeny, erosion never loses. For a relatively zakelijke energie vergelijken short time, though, the mountains prevail by rising faster than they are destroyed. In what Love has called “some of the greatest localized vertical displacement known anywhere in the world,” the Wind Rivers rose sixty thousand feet with respect to the rock around them, the Uintas fifty thousand, others as much. Frequent rains and many streams helped melt them away. West of Wyoming, in the Eocene, there were no Coast Ranges, no Sierra Nevada. Warm winds off the Pacific brought rains to the Rockies, and a climate similar to the present climate of Florida. In the early Eocene, when the ranges in general looked much as they do today, the mountain building ceased. In the tectonic quiet, erosion of course continued, and the broad downwarps among the ranges continued to fill. Then came a footnote to the revolution. “In latest early Eocene, fifty-two million years ago, all hell broke zakelijke energie loose again,” Love said. From thousands of fissures in northwest Wyoming, lava poured forth by the cubic mile. Torn apart by weather and rearranged by streams, it has since been etched out as the Absaroka Range. “After that, everything went blah,” he went on. “In the Oligocene, the tectonic activity was totally dead, and it stayed dead at least until the early Miocene. Thirty million years. Then, in the late Miocene, all hell broke loose again. And all hell has been breaking loose time and again for the last ten million years. This is not a static science.”

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