American conodonts

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They happened to be within a third of a mile of warm-water American conodonts in rock of about the same age which had moved hardly at all. The Scandinavian conodonts had apparently come to Pennsylvania with the closing of the protoAtlantic ocean and been dropped ashore off the leading edge of the arriving plate. “Even I said, ‘Oh, this piece peeled off the oncoming European-African plate and got dumped in here along with the elastics,'” Anita said, telling the story. “Everybody cited those papers. To this day they are called ‘marvellous, landmark papers.’ I could eat my heart out. The papers have been used as prime backup proofs of plate-tectonic applications in the northern Appalachians. Even now, a lot of the people who use the plate-tectonic model for interpreting the Appalachians are completely unaware that those papers were based on a paleontological misinterpretation.” Working in Nevada three years later, Anita had found Scandinavian-style conodonts of middle Ordovician age. Her husband, Leonard Harris, savored the discovery not for its conference room eindhoven embarrassment to his wife, needless to say, but for its air-brake effect on the theory of plate tectonics. “Now, how could that be?” he would ask. “How did this happen? Europe can’t hit you in Nevada.” From the Toiyabe Range she had taken the cool-water fossils, and moving east to other mountains-from basin to range-she had come to middle Ordovician carbonates that contained a mixture of conodonts of both the cool-water and the warm-water varieties, the American and the Scandinavian styles. Fartl1er east, in limestone of the same age in Utah, she had found only warm-water conodonts. She realized now the absoluteness of her error. Utah had been pretty conference room haarlem much the western extremity of the vast Bahama-like carbonate platform that covered North America under shallow Ordovician seas. In western Utah, the continental shelf had begun to angle down toward the floor of the Pacific, and in central Nevada the continent had ended in deep cool water.

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