The Acadian mountains

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A third revolution would follow-the Alleghenian Orogeny, in Pennsylvanian-Permian time. Another mountain wave would crest, break, and send its swash to westward. It was all very repetitive, to be sure-the great ranges rising, falling, rising, falling, covering and creating landscapes, as if successive commingling waters were to rush up a beach and freeze. But why? How? You see in rock that geology repeats itself, but you do not see what started the process. In the rivers in rock you find pieces of mountains, but you do not find out why the mountains were there. I said to Anita, “What made the mountains rise?” “The Acadian mountains?” “All of them-Taconic, Acadian, Alleghenian. What made them come up in the first place?” It has been Anita’s style as a geologist to begin with an outcrop and address herself to history co-working space amsterdam from there-to begin with what she can touch, and then to reason her way back through time as far as she can go. A river conglomerate, as tangible rock, unarguably presents the river. The river speaks of higher ground. The volume of sediment that the river has carried can imply a range of mountains. To find Precambrian jaspers in the beds of younger rivers means that the Precambrian, the so-called basement rock, was lifted to form the mountains. These are sensible inferences drawn cleanly through an absence of alternatives. To go back in this way, retrospectively, from scene to shifting scene, is to go down the rock column, groping toward the beginning of the world. There is firm ground some of the way. Eventually, there comes a point where inference will shade into conjecture. In recesses even more remote, conjecture may usurp the original franchise of God. By reputation, Anita is a scientist with an exceptionally practical mind, a geologist with few weaknesses, who is at home in igneous and metamorphic petrology no less than in sedimentology. She has been described as an outstanding biostratigrapher, a co-working space eindhoven paleontologist who knows the rocks in the field and can go up to a problem and solve it. In my question to her, I was, I will confess, rousing her a little. I knew what her answer would be. “I don’t know what made the mountains come up in the first place,” she said. “I have some ideas, but I don’t know. The plate-tectonics boys think they know.”