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571.
Twenty-six of the fifty-seven stone meteorites listed in Huss (1979) from Roosevelt County, New Mexico, have been classified in the present study. Microprobe analyses indicate 15 H type, 9 L type and 2 LL type chondrites. Based on compositional, textural, and locational comparisons, as many as 10 chondrites may be paired to three distinct falls. 相似文献
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Differentiating clay resources in a uniform limestone plain, such as occurs in northern Belize, offers special challenges for the archaeologist. Combining data from soil mapping with petrographic and neutron activation analysis provides a mechanism for distinguishing possible resource areas. This study employed each of these differing avenues of analysis to determine possible clay resource areas used during the Maya Formative in northern Belize Central America. The results indicate that clay usage changed significantly from the Middle Formative period to the end of Late Formative period. These changes suggest a move to increased localized production and resource exploitation by the end of the period. © 2000 John Wiley & Sons, Inc. 相似文献
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This article addresses the taphonomic issues surrounding artifact-bear associations in Yarimburgaz Cave, northwestern Turkey. Our purpose is to evaluate the circumstances of bone assemblage formation in the Middle Pleistocene deposits of the cave, identifying the agencies responsible for the accumulations and the causes of bone damage before and following deposition. Pleistocene species representation, bone damage, body part representation, and mortality data indicate that cave bear remains in Yarimburgaz are unrelated to hominid use of the same site. None of the observations on the cave bear remains contradicts the expectations developed from modern wildlife accounts of modern bear behavior; these accumulations resulted from mortality normally associated with hibernation over many generations of den use. Nonursid carnivores also played roles in bone collection and/or modification. We conclude that at least three distinct biological processes contributed to the formation of the Middle Pleistocene faunas: hibernating bears, bone-collecting carnivores such as wolves, and hominids in descending order of importance. The Yarimburgaz faunas represent palimpsests or overlays of many short-term depositional events, the close spatial associations of which are explained by slow or uneven sedimentation rates inside the cave. Although occupations by hominids appear to have been ephemeral in nature, hominids ultimately discarded nearly 1700 stone artifacts in Yarimburgaz Cave. The hominids did not discard many ungulate bones in the same circumstances. These observations suggest that hominid foraging efforts focused on resources other than large game while at the cave. © 1996 John Wiley & Sons, Inc. 相似文献