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851.
A study of the trace and minor element content of steatite artifacts from the Eastern United States has been carried out. Samples from both quarry and habitation sites ranging from New York to North Carolina have been analyzed through the use of instrumental neutron activation analysis. The most successful method of evaluating data has involved the study of a very coherent group of elements known as the Rare Earths. Geological processes cause fractionation of this group and it is this fractionation which is of use in terms of characterizing the source deposits of this material. Promising but less definitive results have been obtained with the elements scandium, chromium, cobalt and others. Sufficient variations have been found to be present in the source deposits of steatite in this area to enable differentiation, and the successful linking of samples from habitation sites to their quarry deposits has been achieved in some cases. This paper discusses the results of this study to date, the methods employed, and the potential value of this work in helping to reconstruct prehistoric trading systems. 相似文献
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Most of the research on the intraurban migration attempting to develop models of the mobility process has presented intuitively appealing statements about the residential decision process, but stopped short of a formal development of these concepts. If it is to be possible to predict the mobility pattern within the city, both the search and selection process must be more clearly specified. In this paper, a preliminary theoretical model containing decision rules similar to those found in optimal search models is developed. The model explicitly incorporates the spatial and temporal aspects of residential choice and has the potential to predict the probability that a prospective migrant will search for a new residence in a given area of the city, the time when the search process will come to a conclusion and, by implication, the expected location of the new residence. The preliminary results from the model suggest a major elaboration of the spatial and temporal aspects of residential choice under conditions of uncertainty in terms of a set of empirically measurable determinants, relating to a household's preferences, beliefs, and degree of risk aversion. 相似文献
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C. J. O. Harrison 《Journal of archaeological science》1978,5(4):373-376
The domesticated Red Jungle-fowl G. gallus is believed to have been dispersed by man from India during the Holocene. The distal end of a radius from the Ipswichian Interglacial deposits at Crayford, Kent, was indistinguishable from that of the wild form of Red Jungle-folw. A coracoid from the early Middle Pleistocene of N Norfolk was also very similar to that species but showed differences comparable with those found between different species of Gallus. At least one species referable to Gallus is known from the Pliocene of South-eastern Europe. Extrapolating from zoogeographical speciation patterns it would be possible for a Gallus species to have evolved through Pleistocene speciation in the European region. The species might have become extinct during a glaciation or have been exterminated by early man. A new species Gallus europaeus is described with the coracoid as a holotype, and the radius from Kent is tentatively referred to it. 相似文献
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