At depths of nine thousand to fifteen thousand feet, she discovered, conodonts would turn light brown in roughly ten million years. If they spent ten million years at, say, eighteen thousand feet, they would be dark brown. In comparable amounts of time but at greater and greater depths, they would turn black, gray, opaque, white, clear as crystal. Anita also cooked conodonts in pressure bombs, because it had been suggested to her that the pressures of great tectonism-the big dynamic events in the crust, with mountains building and whole regions being kneaded like dough-might also affect conodont colors. Her experiments convinced her that pressure has little effect on color; heat is what primarily causes it to change. Of course, plenty of heat is produced by deep burial during major tectonic events. Her conodonts from New Jersey were black and from Kentucky pale essentially flexplek huren groningen because huge disintegrating eastern mountain ranges had buried the near ones very deep and the far ones scarcely at all. The East is for the most part the wreckage of the Ancestral Appalachians, and-as is exemplified in the Devonian rock of New York-the formations are thickest close to where the mountains stood. A continuous sedimentary deposit that is thousands of feet thick in eastern Pennsylvania may be ten feet thick in Ohio. Where oil was first discovered in western Pennsylvania, it was seeping out of rocks and running in the streams. It is of a character and purity so remarkable that people used to buy it and drink it for their health. Anita looked at conodont samples from rock that surrounded this truly exceptional oil. In the temperature range of eighty to a hundred and twenty degrees, they were in the center of the petroleum window. They were golden brown. With a year of tests flexplek huren amsterdam nm, with Kodachrome pictures, with graphs and charts of what she called her “wind-tunnel models,” she was prepared to tell her story. The Geological Society of America was to meet in Florida in November, i974, and she arranged to deliver a paper there. “I prepared carefully-I always do-so I wouldn’t phumpfer. But the G.S.A. meeting was not momentous. They were academics, and not particularly knowledgeable about exploration techniques.” Five months later, scarcely knowing what to anticipate, she went to Dallas and spoke before the American Association of Petroleum Geologists.