In Suspect Terrain

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She thought at first there was something wrong with her samples, but her adviser told her that in all likelihood the blackness was merely the result of pressures attendant when the limestone or dolomite was being deformed. He did not encourage her to make a formal study of the matter, and she returned to her absorptions with conodont biostratigraphy. On one of her trips east, she crossed New York State, collecting dolomite and limestone all the way. From Lake Erie to the Catskills, New York State is a cake of Devonian rock, lying flat in a swath sixty miles wide. You can travel across it chipping off rock of the same approximate age, and not just any old Devonian samples-for the Devonian period covers forty-six million yearsbut, say, limestone flexplek huren rotterdam and dolomite from the Gedinnian age, which is seven million years of early Devonian, or even from the Helderbergian stage of middle Gedinnian time. For as much as a hundred and fifty miles, you could follow a line of time no broader than three million years. You could cut it that fine. Anita did something of the sort, and crushed the rocks at Ohio State. She noticed that the conodonts were amber in Erie County, tan in Schuyler and Steuben. They were cordovan in Tioga and Broome. In Albany County, they were dark as pitch. She wondered what the colors might be suggesting about the geologic history of the region. Nothing much, her adviser assured her. The colors were the results of tectonic pressures. It had been just a passing thought. She let it go, and went back to work on her thesis, which would be titled “Stratigraphy and Conodont Paleontology of Upper Silurian and Lower Devonian Rocks of New Jersey, Southeastern New York, and Eastern Pennsylvania.” She was documenting subtle evolutionary differences in conodonts close to the Silurian-Devonian boundary, a point in time just over four hundred million years ago. And, arranging her microfossils in chronicle form, she was differentiating and cataloguing in time the units of rock from which they had flexplek huren amsterdam been removed. This in turn would help her to understand the structure of the country in which she had picked up the rock. Conodont colors faded in her mind. By ig66, having completed their course work at Ohio State, Anita and Jack Epstein had returned to work for the Geological Survey-he to concentrate on northern-Appalachian geology and she to take what she could get, which was a map-editing job in Washington. She would have preferred to work on conodonts, but the federal budget at that time covered only one conodont worker, and someone else had the job. Before long, she had become general editor of all geologic mapping taking place east of the Mississippi River. She dealt with hundreds of geologists.

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