Fresh mountain range

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You would first have had the rock of the lower strata lying flat-a conglomerate with small b1ight pebbles like effervescent bubbles in a matrix red as wine. Then the forces that had compressed the region and produced mountains would have tilted the red conglomerate, not to the vertical, where it stood now, but to something like fortyfive degrees. That mountain range wore away-from peaks to hills to nubbins and on down to nothing much but a horizontal line, the bevelled surface of slanting strata, eventually covered by a sea. In the water, the new sediment of the upper formation would have zakelijke energie accumulated gradually upon that surface, and, later, the forces building a fresh mountain range would have shoved, lifted, and rotated the whole package to something close to its present position, with its lower strata nearly vertical and its upper strata aslant. Here in Carlin Canyon, basin-and-range faulting, when it eventually came along, had not much affected the local structure, further tilting the package only two or three degrees. Clearly, if you were going to change a scene, and change it again and again, you would need adequate time. To made the rock of that lower formation and then tilt it up and wear it down and deposit sediment on it to form the rock above would require an immense quantity of time, an amount that was expressed i? the clean, sharp line that divided the formations-the angular unconformity itself. You could place a finger on that line and touch forty million years. The zakelijke energie vergelijken lower formation, called Tonka, formed in middle Mississippian time. The upper formation, called Strathearn, was deposited forty million years afterward, in late Pennsylvanian time. Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene . . . In the long roll call of the geologic systems and series, those formations-those discrete depositional events, those forty million years-were next-door neighbors on the scale of time. The rock of the lower half of that hill dated to three hundred and forty million years ago, in the Mississippian, and the rock above the unconformity dated to three hundred million years ago, in the Pennsylvaniad. If you were to lift your arms and spread them wide and hold them straight out to either side and think of the distance from fingertips to fingertips as representing the earth’s entire history, then you would have all the principal events in that hillside in the middle of the palm of one hand.

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