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.He would still be inside when that happened, not out in the cities of the "cold" people dying with his fellows.Dar Lang Ahn, by sheer necessity, would become a Teacher; and Nils Kruger would not lose his little friend.-Chapter XII — Geology; ArcheologyAbyormen is larger than the earth and has a smaller percentage of sea area even in the cold time, so the geologists had a great deal of territory to cover.They did not, of course, attempt to do it all; the basic plan was to attempt enough stratigraphic correlation to get a fir idea of its geological history and, if at all possible, find datable radioactives in the series far enough down to get at least a minimum value for the age of the planet.The last was all the astronomers really wanted, but the biologists had considerably higher standards.They came along, prepared to analyze any fossils found by every technique known to their field.Layer after layer of sedimentary rock was traced, sometimes for miles underground, sometimes only yards before it vanished—perhaps because quakes had shuffled it into a puzzle that took experience to solve, perhaps because the phenomena which had deposited it in the first place had covered only a limited area and the formation pinched naturally.A limestone bed laid down over a million square miles at the bottom of a sea is one thing; a sandstone lens that was once the delta of a stream running into a small lake is something else—sometimes a rather inconvenient something else, when a problem of relative dates is in question.Kruger thanked his luck that Commander Burke was not with this ground party and prayed constantly that he would not overhear any remarks made by the geologists for Dar Lang Ahn was learning a good deal of English as time went on, and there are few places where a photographic memory can make itself more obvious or useful, than in a stratigraphy problem.The geologists without exception regarded the native with aw and felt a friendship for him comparing strongly with Kruger's own.Sooner or later the commander would learn; the boy hoped that by then his little friend's popularity would have reached a point where the old officer would be moved to get rid of his suspicions.Nowhere on the planet did there seem to be structures corresponding with the "shields" which characterize certain parts of Earth.Apparently all the present land surface had been submerged in the not too distant past; there was more than a suggestion that Abyormen suffered much more seismic and orogenic activity than Earth.One of the specialists suggested that a reason for this might lie in the "Long Year" seasonal changes, when the greater part of the sea water was deposited on the ice caps.A seismic check of the cap and the southern hemisphere (not over the south pole) indicated a thickness of nearly thirty-five thousand feet.It was showing at the time the check was made, Theer never shone on this part of the planet, and Arren would not irse for several terrestrial years.While several of Abyormen's short years passed before any absolute dating of strata was possible, the astronomers learned what they had feared rather quickly.From the beginning, of course, the geologists had kept their eyes open for pegmatites and other igneous intrusions which might contain radioactives suitable for dating, and fairly soon these were found at several places on the continent they were examining.It was not possible to correlate these rocks with the sedimentaries, at the time, but one of them had a uranium-lead ratio corresponding to an age of just under one and a half billion years.It was a large sample, and ten independent checks were run, none varying more than about twenty million years from the mean.Since the astronomers were not willing to believe that Alcyone had been in existence longer than something like one percent of that time they accepted the information a trifle glumly.But dated or not, the sedimentaries had their own fields of interest.If Dar Lang Ahn had ever seen a fossil in his life he had never given it a second thought [ Pobierz całość w formacie PDF ]