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Through use of methodology common in sedimentary geology, we apply U–Pb ages of detrital zircons to source nonlocal temper sand in an ancient ceramic assemblage recovered from Roviana Lagoon of the New Georgia Group in the Solomon Islands. Most potsherds from the Roviana Lagoon contain local volcanic sand as temper, but a small number of sherds contain anomalous granitic temper sand that does not appear to be local. To determine the origin of the anomalous temper, ages of zircons from the anomalous Roviana sherds are compared with ages of zircons in materials from Lizard Island off the Queensland coast and in sand from Muyuw Island in the Solomon Sea where generically similar granitic sands occur. U–Pb analyses of grains from the Roviana sherds yield Middle Miocene ages, while analyses of grains from Lizard Island granitic bedrock, sand, and local potsherds yield much older Permian-Triassic ages, disproving any possibility that the Roviana sherds were derived from Lizard Island, but suggesting local production of the Lizard Island sherds. Ages of grains in a sand sample from Muyuw Island are nearly identical to the ages of grains in the Roviana sherds. All grains in the Muyuw sand are Middle Miocene in age, overlapping closely with the Roviana age population. This strong similarity in detrital zircon signals indicates that the Roviana temper was likely derived from Muyuw Island sands. Our test case for the use of U–Pb ages of detrital zircons in sourcing temper sands is of only regional significance, and not of intrinsic global interest. The methodology, however, should find wide applicability for sourcing temper sands in many parts of the world, for it provides more specific data for the origins of tempers than either petrographic or chemical analysis.  相似文献   
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This paper examines how the practices of heritage tourism reproduce identities in and of Fredericksburg, Virginia. In particular, we focus on the everyday practices of tourism workers who are essential in the representation and reproduction of this heritage space. In so doing, we want to move away from research in geography that theorizes representation and embodiment as distinct realms of experience and inquiry. Instead, we argue that representation is work and within this very material process, city workers weave memory with history as they guide visitors through ‘America’s Most Historic City'. Through an examination of three of Fredericksburg's tourism work environments we show how representations succeed in reproducing heritage tourism spaces precisely because representation is work.  相似文献   
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The author, based on field work, interviews, and examination of local and regional literature and official statistical sources, compares the experience in agrarian reform in two disparate locations—KostToma Oblast, northeast of Moscow in the Noncher-nozem Region, and Rostov Oblast on Russia's Black Sea littoral in the fertile Chernozem (Black Earth) region. It examines both the reorganization of state and collective farms and the establishment of private peasant farms in the two oblasts, with particular emphasis on the latter. The sections on private farms represent an initial attempt, based on in-depth information for a limited sample population, to garner insights, at the rayon level, into factors that may be influencing regional variations in the number, size, and location of private farms across the Russian countryside. 2 maps, 6 tables, 53 references.  相似文献   
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