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1.
G. DE G. SIEVEKING P. BUSH J. FERGUSON P. T. CRADDOCK M. J. HUGHES M. R. COWELL 《Archaeometry》1972,14(2):151-176
This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed. 相似文献
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A method is described for the identification of the origin of flint artefacts. The method is based on the variation in the trace element concentrations for different origins. The trace element concentrations were determined by non-destructive neutron activation analysis. The identification was obtained from a pattern recognition analysis. 相似文献
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Roger M. A. Allen 《Muslim world (Hartford, Conn.)》1972,62(2):115-125
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Roger Allen Catherine Asher Michael Bates Daniel Bradburd Robert L. Canfield Howard Crane 《Iranian studies》1995,28(3-4):231-281
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J. L. Allen 《Journal of Historical Geography》1978,4(4):357-370
One of the major features of the continental geography of North America that was still misunderstood at the beginning of the nineteenth century was the drainage system between the Mississippi River and the Pacific. At the beginning of the century, Americans thought of the drainage system as symmetrical, with all major streams heading in a common source region and flowing in several directions to the Mississippi, the Arctic, the Pacific and the Gulf of California. The desired water route across the continent was based upon this view. During the first half of the nineteenth century the concept of the common source region and the water route underwent revision. Geographical information from early explorers like Lewis and Clark and Pike reinforced the older theories but gradually gave way before more accurate data acquired by the men of the Rocky Mountain fur trade. The fur trade lore was tested by John Charles Frémont in the 1840's and a new image was developed, one of a continental divide rather than a common source region. Although the idea of a commercial route across the continent still persisted after Frémont, it was viewed as a land route, crossing the Continental Divide at South Pass, rather than one by water. 相似文献
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