Push up some mountains. Cut them down. Drown the land under the sea. Push up some more mountains. Cut them down. Push up a third set of mountains, and let the river cut through them. “Unconformity” is the geologic term for an old, eroded land surface buried under younger rock layers. Put your outspread hand over the Carlin Canyon, Nevada unconformity and your fingers span roughly forty million years- the time that it took to bevel down the first set of mountains and deposit the younger layers on top. What is forty million years? Enough time for a small predatory dinosaur to evolve into a bird. Enough time for a four-legged, deer-like mammal to evolve into a whale. And far more than enough time to turn an ape-like creature in eastern Africa into a big-brained biped who can marvel at such things. The Grand Canyon’s Great Unconformity divides 1.7 billion-year-old rock from 550 million-year-old rock, a gap of more than one billion years. One billion years. I earn my salary studying the Earth and teaching its history, but I admit utter helplessness in comprehending such a span. A billion pages like those of this book would stack up more than forty miles. I had lived one bullion seconds a few days before my thirty-second birthday. A tape measure one billion inches long would stretch two-thirds of the way around the Earth. Such analogies hint at what deep time means- but they don’t get us there. “The human mind may not have evolved enough to be able to comprehend deep time, " John McPhee once observed, “it may only be able to measure it. . Keith Meldahl
The sunlight claps the earth, and the moonbeams kiss the sea: what are all these kissings worth, if thou kiss not me?
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Percy Bysshe Shelley
In youth, it was a way I had, To do my best to please. And change, with every passing lad To suit his theories. But now I know the things I know And do the things I do, And if you do not like me...
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Dorothy Parker
If I were a tree, I would have no reason to love a human.
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Maggie Stiefvater
A kiss is a lovely trick designed by nature to stop speech when words become superfluous.
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Ingrid Bergman
This life is yours. Take the power to choose what you want to do and do it well. Take the power to love what you want in life and love it honestly. Take the power to walk in the forest and be a part of...
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Susan Polis Schutz
More Quotes By Keith Meldahl
Push up some mountains. Cut them down. Drown the land under the sea. Push up some more mountains. <span style="margin:15px; display:block"></span>Cut them down. Push up a third set of mountains, and let the river cut through them. “Unconformity” is the geologic term for an old,...
Earth processes that seem trivially slow in human time can accomplish stunning work in geologic time. Let the Colorado River erode its bed by 1/100th of an inch each year (about the thickness of one of your fingernails.) Multiply it by six million years, and...
Each scenario is about fifteen million years into the future, and each assumes that the Pacific Plate will continue to move northwest at about 2.0 inches per year relative to the interior of North America.In scenario 1, the San Andreas fault is the sole locus...
