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1 " To encounter the sacred is to be alive at the deepest center of human existence. Sacred places are the truest definitions of the earth; they stand for the earth immediately and forever; they are its flags and shields. If you would know the earth for what it really is, learn it through its sacred places. At Devil’s Tower or Canyon de Chelly or the Cahokia Mounds, you touch the pulse of the living planet; you feel its breath upon you. You become one with a spirit that pervades geologic time and space. "
― N. Scott Momaday
2 " It is not only the size of these redwoods but their strangeness that frightens them. And why not? For these are the last remaining members of a race that flourished over four continents as far back in geologic time as the upper Jurassic period. Fossils of these ancients have been found dating from the Cretaceous era while in the Eocene and Miocene they were spread over England and Europe and America. And then the glaciers moved down and wiped the Titans out beyond recovery. And only these few are left--a stunning memory of what the world was like once long ago. Can it be that we do not love to be reminded that we are very young and callow in a world that was old when we came into it? And could there be a strong resistance to the certainty that a living world will continue its stately way when we no longer inhabit it? "
― John Steinbeck
3 " 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. "
4 " The geologic cycle is a bunch of balarky. "
5 " The geologic column is a bunch of balarky. "
6 " 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 you’ve carved the Grand Canyon. Take the creeping pace of which the continents move (about two inches per year on average, or roughly as fast as your fingernails grow). Stretch that over thirty million years, and a continent will travel nearly 1,000 miles. Stretch that over a few billions years, and continents will have time to wander from the tropics to the poles and back, crunching together to assemble super-continents, break apart into new configurations- and do all of that again several times over. Deep time, it could be said, is Nature’s way of giving the Earth room for its history. The recognition of deep time might be geology’s paramount contribution to human knowledge. "
― , Rough-Hewn Land: A Geologic Journey from California to the Rocky Mountains
7 " When we look out into space, we're looking back in time; the light from a galaxy a billion light-years away, for instance, will take a billion years to reach us. It's an amazing thing. The history is there for us to see. It's not mushed up like the geologic record of Earth. You can just see it exactly as it was. "